tag:blogger.com,1999:blog-4071848661727197032024-03-08T02:37:24.664-08:00The 8 Phylum of Invertebrate Animals Anonymoushttp://www.blogger.com/profile/15125980005528241488noreply@blogger.comBlogger8125tag:blogger.com,1999:blog-407184866172719703.post-5185129976166212592012-10-16T08:24:00.001-07:002012-10-16T08:24:11.051-07:00Phylum Arthropoda/ Arthropods (8th Phylum)<br />
<span style="font-size: large;"><span style="font-size: medium;">This is the largest and most successful of the animal phyla, with over 1 000 000 species identified to date and an estimated 1 000 000 000 000 000 000 (1 quintillion) individuals alive today. Some scientists estimate that there are over 200 million insects for each single person. That's just insects alone, and doesn't include the countless millions of spiders, crustaceans, millipedes, centipedes, etc that make up the phylum Arthropoda.</span></span><br />
<span style="font-size: large;"><span style="font-size: medium;">Arthropods are the most easily identifiable of all the animals, as they all share several things in common that no other animals share. First, all arthropods are protected by a hard exoskeleton (outer skeleton) composed of chitin (humans and other chordates have endoskeletons). This exoskeleton protects the organs, gives support for the body, and allows for efficient locomotion. However, because the exoskeleton cannot grow, it must periodically be shed to allow for the organism to grow.</span></span><br />
<span style="font-size: large;"><span style="font-size: medium;">All arthropods have segmented bodies divided into a head, thorax, and abdomen. In some cases, such as with the lobster, the head and thorax are fused together. This is called a cephalothorax. Arthropods also have jointed appendages.</span></span><br />
<span style="font-size: large;"><span style="font-size: medium;">Arthropods have a complex internal design, with ganglia for a brain and an organ that acts as a heart. They have a complete digestive and excretory system. They also have well-developed sensory organs, that include antennae, eyes, and in some cases internal ears. Respiration occurs through the body surface, gills, trachea, and/or book lungs. The oxygen is carried in an open circulatory system (humans have a closed circulatory system).</span></span><br />
<span style="font-size: large;"><span style="font-size: medium;">Arthropods are very diverse, and therefore can locomote in a wide variety of ways. They can walk, crawl, climb, hop, fly, glide, swim, skate, dive — almost every type of locomotion imaginable (other than drive!).</span></span><br />
<span style="font-size: large;"><span style="font-size: medium;">Arthropods can be found on every continent and in every ocean, from the harsh climate of Antarctica to the dryness of the desert to the dampness of the rainforests, and even to the darkness of the ocean's depths. They can be found in ponds, on plants, in and on other animals, and even in your own house!</span></span><br />
<span style="font-size: large;"><span style="font-size: medium;">Because this phylum is so large, there are numerous ways of classifying it. Below is the most widely-accepted 4-subphylum method of dividing this large phylum. While there are several other methods, including one in which Diplopoda and Chilopoda are divided into four separate classes, I believe this one to be the most accurate to date:</span></span><br />
<span style="font-size: large;"><span style="font-size: medium;">Subphylum Trilobita<br />This large subphylum consists of the trilobites, which are only known by the fossil record. This subphylum therefore is extinct.</span></span><br />
<span style="font-size: large;"><span style="font-size: medium;">Subphylum Chelicerata<br />Consists of arthropods that have 6 pairs of appendages, four of which are legs (or five in the case of the horseshoe crab). They lack antennae and mandibles. There are 3 classes:</span></span><br />
<span style="font-size: large;"><span style="font-size: medium;"><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Arachnida (spiders, ticks, mites, scorpions)<br /><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Merostomata (horseshoe crabs)<br /><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Pycnogonida (sea spiders)</span></span><br />
<span style="font-size: large;"><span style="font-size: medium;">Subphylum Crustacea<br />This subphylum contains 30 000 species of arthropods that lead mostly aquatic lives. They have two pairs of antennae and mandibles. There are 5 classes:</span></span><br />
<span style="font-size: large;"><span style="font-size: medium;"><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Branchiopoda (fairy shrimp, water fleas)<br /><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Cephalocarida (small crustaceans)<br /><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Malacostraca (isopods, amphipods, krill, crabs, shrimp, lobsters)<br /><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Maxillopoda (copepods, barnacles)<br /><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Remipedia (small, recently discovered crustaceans)</span></span><br />
<span style="font-size: large;"><span style="font-size: medium;">Subphylum Uniramia<br />This is the largest of the subphyla. These arthropods have one pair of antennae and one or two maxillae. They also have mandibles. Respiration occurs through the trachea, body surface and/or gills. There are 3 classes:</span></span><br />
<span style="font-size: large;"><span style="font-size: medium;"><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Chilopoda (centipedes)<br /><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Diplopoda (millipedes)<br /><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Insecta (insects)</span></span><br />
<span style="font-size: large;"><span style="font-size: medium;"><b>THE OLD 4-CLASS TAXONOMIC SYSTEM</b></span></span><br />
<span style="font-size: large;"><span style="font-size: medium;"><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Arachnida (spiders, sea spiders, ticks, mites, scorpions)<br /><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Crustacea (crabs, lobsters, horseshoe crabs, krill, shrimp, barnacles, fairy shrimps, etc)<br /><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Insecta (insects)<br /><img src="http://www.angelfire.lycos.com/doc/images/ballsq/blueball.gif" /> Myriapoda (centipedes and millipedes)</span></span><br />
Anonymoushttp://www.blogger.com/profile/15125980005528241488noreply@blogger.com1tag:blogger.com,1999:blog-407184866172719703.post-49125208924758801212012-10-16T08:21:00.000-07:002012-10-16T08:21:07.896-07:00Phylum Echinodermata/ Echinoderms (7th Phylum)<table border="0" cellpadding="4" cellspacing="1" style="font-family: Tahoma, 'Franklin Gothic Medium', Arial;"><tbody>
<tr><td style="font-size: 10pt;">There are 5 related classes in the phylum Echinodermata (the Latin name means "spiny-skinned"). For a detailed list with all classifications <a href="http://www.calacademy.org/research/izg/echinoderm/classify.htm" style="color: #004080;" target="_blank">click here</a>:<br />
<ul style="border-width: 0px; left: 0px; margin-left: 0px; padding: 0px;">
<li style="list-style-type: disc;"><a href="http://www.starfish.ch/reef/echinoderms.html#starfish" style="color: #004080;">Sea star or starfish (Asteroidea)</a></li>
<li style="list-style-type: disc;"><a href="http://www.starfish.ch/reef/echinoderms.html#brittle" style="color: #004080;">Brittle stars, basket stars, serpent stars (Ophiuroidea)</a></li>
<li style="list-style-type: disc;"><a href="http://www.starfish.ch/reef/echinoderms.html#urchin" style="color: #004080;">Sea urchins, heart urchins and sanddollars (Echinoidea)</a></li>
<li style="list-style-type: disc;"><a href="http://www.starfish.ch/reef/echinoderms.html#cucumber" style="color: #004080;">Holothurians or sea cucumbers (Holothuroidea)</a></li>
<li style="list-style-type: disc;"><a href="http://www.starfish.ch/reef/echinoderms.html#feather" style="color: #004080;">Feather stars and sea lilies (Crinoidea)</a>.</li>
</ul>
<h4>
<span style="color: #0066ff;">Characteristics of Echinoderms</span></h4>
Echinoderms are characterized by radial symmetry, several arms (5 or more, mostly grouped 2 left - 1 middle - 2 right) radiating from a central body (= pentamerous). The body actually consists of five equal segments, each containing a duplicate set of various internal organs. They have no heart, brain, nor eyes, but some brittle stars seem to have light sensitive parts on their arms. Their mouth is situated on the underside and their anus on top (except feather stars, sea cucumbers and some urchins).<br />
Echinoderms have tentacle-like structures called tube feet with suction pads situated at their extremities. These tube feet are hydraulically controlled by a remarkable vascular system. This system supplies water through canals of small muscular tubes to the tube feet (= ambulacral feet). As the tube feet press against a moving object, water is withdrawn from them, resulting in a suction effect. When water returns to the canals, suction is released. The resulting locomotion is generally very slow.<br />
<h4>
<span style="color: #0066ff;">Ecology and range of Echinoderms</span></h4>
Echinoderms are exclusively marine. They occur in various habitats from the intertidal zone down to the bottom of the deep sea trenches and from sand to rubble to coral reefs and in cold and tropical seas.</td></tr>
<tr><td style="font-size: 10pt;" valign="top"><h4>
</h4>
</td><td style="font-size: 10pt;"> </td><td style="font-size: 10pt;" valign="top"><h4>
<span style="color: #0066ff;">Behavior of Echinoderms</span></h4>
Some echinoderms are carnivorous (for example starfish) others are detritus foragers (for example some sea cucumbers) or planktonic feeders (for example basket stars).<br />
Reproduction is carried out by the release of sperm and eggs into the water. Most species produce pelagic (= free floating) planktonic larvae which feed on plankton. These larvae are bilaterally symmetrical, unlike their parents (illustration of a larvae of a sea star below). When they settle to the bottom they change to the typical echinoderm features.<br />
<div align="center">
<img alt="Larvae of a starfish" height="95" src="http://www.starfish.ch/Zeichnung/Illustrationen/SeesternLarve.gif" style="border-color: rgb(0, 0, 0);" width="387" /></div>
Echinoderms can regenerate missing limbs, arms, spines - even intestines (for example sea cucumbers). Some brittle stars and sea stars can reproduce asexually by breaking a ray or arm or by deliberately splitting the body in half. Each half then becomes a whole new animal.<br />
Echinoderms are protected through their spiny skins and spines. But they are still preyed upon by shells (like the triton shell), some fish (like the trigger fish), crabs and shrimps and by other echinoderms like starfish which are carnivorous. Many echinoderms only show themselves at night (= nocturnal), therefore reducing the threat from the day time predators.<br />
Echinoderms serve as hosts to a large variety of <a href="http://www.starfish.ch/reef/echinoderms.html#symbiotic" style="color: #004080;">symbiotic</a> organisms including shrimps, crabs, worms, snails and even fishes.</td></tr>
<tr><td colspan="3" style="font-size: 10pt;"><div align="center">
<img height="3" src="http://www.starfish.ch/image/bars/Abar-korallenriff.gif" style="border-color: rgb(0, 0, 0);" width="100%" /></div>
</td></tr>
<tr><td style="font-size: 10pt;" valign="top"><h5>
<span style="color: blue;">Sea stars (starfish)<a href="" name="starfish"></a></span></h5>
(Asteroidea)<img alt="Seestern" height="128" src="http://www.starfish.ch/Zeichnung/Illustrationen/c-Seestern.gif" style="border-color: rgb(0, 0, 0);" width="132" /></td><td style="font-size: 10pt;" valign="top"> </td><td style="font-size: 10pt;" valign="top"><h4>
<span style="color: #0066ff;">Characteristics of sea stars (or starfish)</span></h4>
Sea stars are characterized by radial symmetry, several arms (5 or multiplied by 5) radiating from a central body. Mouth and anus are close together on the underside, the anus is at the center of the disc together with the water intake (madreporite). The upper surface is often very colorful. Minute pincer-like structures called pedicellaria are present. These structures ensure that the surface of the arms stay free from algae. The underside is often a lighter color.<br />
There are a few starfish that have 6 or 7 arms, for example Echinaster luzonicus or Protoreaster, some even more like the elven-armed sea star (Coscinasterias calamaria). Others normally have 5 arms but now have more arms, because after an injury an arm divided and grew into two arms.<br />
<h4>
<span style="color: #0066ff;">Ecology and range or sea stars</span></h4>
The starfish lives everywhere in the coral reef and on sand or rocks.<br />
<h4>
<span style="color: #0066ff;">Behavior of sea stars</span></h4>
</td></tr>
<tr><td style="font-size: 10pt;" valign="top"><div align="center">
<div align="left">
<span style="color: blue;"><b>Regeneration<a href="" name="Regeneration"></a></b></span>The ability of an organism to grow a body part that has been lost</div>
<div align="left">
<span style="color: blue;"><b>Autotomy</b></span><br />The spontaneous self amputation of an appendage when the organism is injured or under attack. The autotomized part is usually regenerated.</div>
<div align="left">
<b><span style="color: blue;">Budding</span></b><br />Is asexual reproduction in which an outgrowth on the parent organism breaks off to form a new individual</div>
<div align="left">
<span style="color: blue;"><b>Fission</b></span>Self-division into two parts, each of which then becomes a separate and independent organisms (asexual reproduction)</div>
</div>
</td><td style="font-size: 10pt;" valign="top"> </td><td style="font-size: 10pt;" valign="top">The majority of sea stars are carnivorous and feed on sponges, bryozoans, ascidians and molluscs. Other starfishes are detritus feeders (detritus = organically enriched film that covers rocks) or scavengers. Some starfish are specialized feeders, for example the crown-of-thorns that feeds on life coral polyps.<br />
Starfish have no hard mouth parts to help them capture prey. The stomach is extruded over the prey, thus surrounding the soft parts with the digestive organs. Digestive juices are secreted and the tissue of the prey liquefied. The digested food mass, together with the stomach is then sucked back in. This method can be observed, if you turn around a starfish, that sits on prey or sand - you will see the stomach retreating.<br />
Starfish are well known for their powers of regeneration. A complete new animal can grow from a small fragment such as a arm. In some species (Linckia multifora and Echinaster luzonicus) one of the arms will virtually pull itself away, regenerates and forms a new animal. Autotomy (self amputation) usually is a protective function, losing the body part to escape a predator rather than being eaten. But here it serves as a form of asexual reproduction. In other species of sea stars (Allostichaster polyplax and Coscinasterias calamaria) the body is broken into unequal parts (= fission) then the missing limbs regenerate.<br />
<strong>Predators of starfishes</strong><br />
<table border="0" style="width: 100%px;"><tbody>
<tr align="center" valign="top"><td style="font-size: 10pt;" width="33%"><div align="center">
<a href="http://www.starfish.ch/Fotos/molluscs-Weichtiere/shells-Schnecken/Charonia-tritonis1.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/molluscs-Weichtiere/shells-Schnecken/Charonia-tritonis1.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a></div>
Triton Trumpet - Charonia tritonis</td><td style="font-size: 10pt;" width="33%"><div align="center">
<a href="http://www.starfish.ch/Fotos/crustaceans-Gliederfuesser/shrimps-Garnelen/Hymenocera-elegans.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/crustaceans-Gliederfuesser/shrimps-Garnelen/Hymenocera-elegans.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
<a href="http://www.starfish.ch/invertebrates-Wirbellose/crustaceans-Gliederfuesser/Hymenocera-elegans.html" style="color: #004080;">INFO</a> - Harlequin Shrimp - Hymenocera elegans</div>
</td><td style="font-size: 10pt;" width="33%"><div align="center">
<div align="center">
<a href="http://www.starfish.ch/Fotos/crustaceans-Gliederfuesser/true-crabs-Krabben/Trapezia-sp-1.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/crustaceans-Gliederfuesser/true-crabs-Krabben/Trapezia-sp-1.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a></div>
<div align="center">
Reef Crab - Trapezia sp</div>
</div>
</td></tr>
</tbody></table>
The crown-of-thorns (Acanthaster planci) is one of the largest and the most venomous starfishes. It can reach 50 cm diameter and has numerous (10 to 20) spiny arms with formidable thorn like toxic spines. Don't touch them! A species of small cardinalfishes (Siphamia fuscolineata) and a commersal shrimp (Perliclimenes soror) live among those spines. The crown-of-thorns feed on live coral polyps. They "graze" the corals which are left behind white and dead. Their predators are the giant triton shell (Charonia tritonis) and some puffer fish. <a href="http://www.int-res.com/articles/meps/214/m214p111.pdf" style="color: #004080;" target="_blank">Scientist</a> have also found out, that some crown of thorns are deterred from eating the coral polyps by the small crabs living among the coral branches (Trapezia sp). These crabs defend their coral host by breaking them off at the pedicellaria. Other small crabs (Tetralia sp) only pinch the tube feets of the starfish. Crown of thorns prefer corals, that are not hosts to these crabs.<br />
The cushion<a href="" name="cushion"></a> star (Culcita nouvaeguineae) doesn't look like a starfish at all, more like a large sea urchin without spines. Its pentagonal appearance gives only the slightest indication that this organism is related to other starfish.</td></tr>
<tr><td colspan="3" style="font-size: 10pt;"><h4 align="center">
Photos of sea stars (<a href="http://www.starfish.ch/c-invertebrates/seesterne.html" style="color: #004080;">photo collection</a>) click for enlargement</h4>
<table style="width: 100%px;"><tbody>
<tr align="center" valign="top"><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/starfish-Seesterne/Acanthaster-planci2.jpg" style="color: #004080;"><img alt="Crown-of-thorns starfish (Acanthaster planci)" border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/starfish-Seesterne/Acanthaster-planci2.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Crown-of-thorns starfish (Acanthaster planci)<br />
</td><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/starfish-Seesterne/Culcita-schmideliana5.jpg" style="color: #004080;"><img alt="cushion star - Kissenstern" border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/starfish-Seesterne/Culcita-schmideliana5.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Spiny Cushion Starfish - Culcita schmideliana</td><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/starfish-Seesterne/Fromia-monilis1.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/starfish-Seesterne/Fromia-monilis1.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Necklace Sea Star - Fromia monilis<br />
</td></tr>
<tr align="center" valign="top"><td style="font-size: 10pt;"><a href="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/starfish-Seesterne/Nardoa-tuberculata2.jpg" style="color: #004080;"><img alt="Starfish / sea star (Nardoa variolata)" border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/starfish-Seesterne/Nardoa-tuberculata2.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Starfish / sea star (Nardoa variolata)</td><td style="font-size: 10pt;"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/starfish-Seesterne/Protoreaster-nodosus3.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/starfish-Seesterne/Protoreaster-nodosus3.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Horned Sea Star - Protoreaster nodosus<br />
</td><td style="font-size: 10pt;"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/starfish-Seesterne/Gomophia-egyptiaca1.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/starfish-Seesterne/Gomophia-egyptiaca1.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Egyptian Sea Star - Gomophia egyptiaca<br />
</td></tr>
<tr align="center" valign="top"><td style="font-size: 10pt;"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/starfish-Seesterne/Echinaster-luzonicus-regeneration.jpg" style="color: #004080;"><img border="0" height="198" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/starfish-Seesterne/Echinaster-luzonicus-regeneration.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="149" /></a><br />
Regeneration of an arm: Luzon Sea Star- Echinaster luzonicus</td><td style="font-size: 10pt;"><a href="http://www.starfish.ch/Fotos/crustaceans-Gliederfuesser/shrimps-Garnelen/Periclimenes-soror4.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/crustaceans-Gliederfuesser/shrimps-Garnelen/Periclimenes-soror4.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Starfish Shrimp - Periclimenes soror</td><td style="font-size: 10pt;"><a href="http://www.starfish.ch/Fotos/comb-jellies-Rippenquallen/Coeloplana-astericola4.jpg" style="color: #004080;"><img border="0" height="198" src="http://www.starfish.ch/Fotos/thumbnail/comb-jellies-Rippenquallen/Coeloplana-astericola4.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="149" /></a><br />
Comb Jelly on Starfish - Coeloplana astericola<br />
</td></tr>
</tbody></table>
</td></tr>
<tr><td colspan="3" style="font-size: 10pt;"><div align="center">
<img height="3" src="http://www.starfish.ch/image/bars/Abar-korallenriff.gif" style="border-color: rgb(0, 0, 0);" width="100%" /></div>
</td></tr>
<tr><td style="font-size: 10pt;" valign="top"><h5>
<a href="" name="feather"></a><span style="color: blue;">Feather stars</span></h5>
(Crinoidea)<br />
<div align="center">
<img height="115" src="http://www.starfish.ch/Zeichnung/Illustrationen/c-Federstern.gif" style="border-color: rgb(0, 0, 0);" width="107" /></div>
</td><td style="font-size: 10pt;" valign="top"> </td><td style="font-size: 10pt;" valign="top"><h4>
<span style="color: #0066ff;">Characteristics of feather stars</span></h4>
Feather stars also known as crinoids. They are characterized by radial symmetry. The body of a typical feather star is cup-shaped, their numerous feathery arms project from a central disc. Some have five arms, others as many as 200. The arms, called pinnules are coated with a sticky substance that helps to catch food. There are appendages known as cirri attached to the underside of the body with which they cling to to sponges or corals. Both their mouth and their anus are situated on the upper side.<br />
<h4>
<span style="color: #0066ff;">Ecology and range of feather stars</span></h4>
Feather stars are primarily nocturnal but they are seen in the open during the day with their arms rolled up.<br />
<h4>
<span style="color: #0066ff;">Behavior of feather stars</span></h4>
Feather stars can crawl, roll, walk and even swim but usually they cling to sponges or corals. Feather stars are very abundant in areas exposed to periodic strong currents, because they feed on plaktonic food.</td></tr>
<tr><td style="font-size: 10pt;" valign="top"><div align="center">
</div>
</td><td style="font-size: 10pt;" valign="top"> </td><td style="font-size: 10pt;" valign="top">Numerous animals live in close association with feather stars. Echinoderms are hosts to various symbiotic<a href="" name="symbiotic"></a> animals such as the crinoid clingfish (Discotrema crinophila), the elegant squat lobster (Allogalathea elegans) or the crinoid shrimp (Periclimenes sp.). These animals receive shelter and food (left over) and also feed on microorganisms living on feather stars.</td></tr>
<tr><td colspan="3" style="font-size: 10pt;"><div align="center">
<h4>
Photos of feather stars (<a href="http://www.starfish.ch/c-invertebrates/federsterne.html" style="color: #004080;">photo collection</a>) click for enlargement</h4>
<table style="width: 100%px;"><tbody>
<tr align="center" valign="top"><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/featherstars-Federsterne/Stephanometra-echinus.jpg" style="color: #004080;"><img alt="Feather star (Stephanometra " border="0" height="198" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/featherstars-Federsterne/Stephanometra-echinus.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="149" /></a><br />
Feather star (Stephanometra sp.) - <a href="http://www.starfish.ch/invertebrates-Wirbellose/echinoderms-Stachelhauter/Stephanometra-echinus.html" style="color: #004080;">gallery</a><br />
</td><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/featherstars-Federsterne/Lamprometra-sp-1.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/featherstars-Federsterne/Lamprometra-sp-1.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Feather star (Lamprometra) half open, holding on to sponge with its cirri (appendages)</td><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/featherstars-Federsterne/Himerometra-robustipinna.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/featherstars-Federsterne/Himerometra-robustipinna.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Rolled up feather star (Himerometra robustipinna) by day<br />
</td></tr>
<tr align="center" valign="top"><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/featherstars-Federsterne/Crinoidea-sp-2.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/featherstars-Federsterne/Crinoidea-sp-2.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Central body of a feather star with mouth and anus</td><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/featherstars-Federsterne/Pontiometra-andersoni.jpg" style="color: #004080;"><img alt="Pinnules of a feather star (Pontiometra) coated to help catch " border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/featherstars-Federsterne/Pontiometra-andersoni.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Pinnules of a feather star (Pontiometra) coated to help catch food</td><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/crustaceans-Gliederfuesser/shrimps-Garnelen/Laomenes-pardus2.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/crustaceans-Gliederfuesser/shrimps-Garnelen/Laomenes-pardus2.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Crinoid shrimp (Laomenes pardus) on featherstar (Oxycomanthus)</td></tr>
</tbody></table>
</div>
</td></tr>
<tr><td colspan="3" style="font-size: 10pt;"><div align="center">
<img height="3" src="http://www.starfish.ch/image/bars/Abar-korallenriff.gif" style="border-color: rgb(0, 0, 0);" width="100%" /></div>
</td></tr>
<tr><td style="font-size: 10pt;" valign="top"><h5>
<span style="color: blue;">Brittle stars</span><a href="" name="brittle"></a></h5>
(Ophiuroidea)<br />
<div align="center">
<img alt="Schlangenstern" height="71" src="http://www.starfish.ch/Zeichnung/Illustrationen/c-Schlangenstern.gif" style="border-color: rgb(0, 0, 0);" width="178" /></div>
<h5 align="left">
<span style="color: blue;">Basket star</span><a href="" name="Basket"></a></h5>
<div align="left">
(Astroboa nuda)</div>
<div align="center">
<img alt="Gorgonienhaupt" height="169" src="http://www.starfish.ch/Zeichnung/Illustrationen/c-Gorgonienhaupt.gif" style="border-color: rgb(0, 0, 0);" width="168" /></div>
</td><td style="font-size: 10pt;" valign="top"> </td><td style="font-size: 10pt;" valign="top"><h4>
<span style="color: #0066ff;">Characteristics of brittle stars</span></h4>
Brittle stars are close relatives of sea stars. Characterized by radial symmetry with a central body from which five snakelike arms protrude. The arms are highly flexible. There is no replication of internal organs, just one set in the central disk. Compared to starfish, brittle stars have a much smaller central disc and no anus. Wastes are eliminated through the mouth which is situated on the underside center.<br />
On the underside of the body disk there is a splitlike opening at the base of each side of each arm. These ten openings are breathing and reproductive outlets, taking in water for oxygen and shedding eggs or sperm into the sea.<br />
The basket stars are a specialized type of brittle stars. They have a series of complexly branched arms which are used to catch plankton.<br />
Serpent stars are seen coiled snakelike around branches of gorgonians.<br />
<h4>
<span style="color: #0066ff;">Ecology and range of brittle stars</span></h4>
Brittle stars are very cryptic and hide in crevices under corals. Best seen at night time, when they emerge to feed on plankton. Usually at places exposed to strong currents.<br />
Serpent stars feed mostly on small invertebrates like mollusks, worms and crustaceans and are generally found in crevices and beneath rocks or in holes in the sand.<br />
Snake stars (for example Ophiothela danae) are found entwined in the branches of black corals or gorgonians where they feed on the rich mucus of their host, in turn performing cleaning functions.<br />
<h4>
<span style="color: #0066ff;">Behavior of brittle stars</span></h4>
As the name suggests, the arms of the brittle stars are rather liable to break. This is actually an escape mechanism. Those arms regenerate quickly and an entire new organism can regenerate, if the broken arm is attached to a seizable portion of the disk. Brittle stars can reproduce asexually by self-division. Brittle stars are the most active and fastest moving echinoderms.<br />
Brittle stars feed on plankton but also on detritus, coral-shed mucus, bottom detritus (detritus = organically enriched film that covers rocks), mollusks and worms.</td></tr>
<tr><td colspan="3" style="font-size: 10pt;"><h4 align="center">
Photos of brittle stars (<a href="http://www.starfish.ch/c-invertebrates/schlangensterne.html" style="color: #004080;">photo collection</a>) click for enlargement</h4>
<table style="width: 100%px;"><tbody>
<tr align="center" valign="top"><td style="font-size: 10pt;" width="33%"><div align="center">
<a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/brittlestars-Schlangensterne/Ophiothela-sp-1.jpg" style="color: #004080;"><img alt="coral with brittle stars - Koralle mit Haarsternen" border="0" height="198" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/brittlestars-Schlangensterne/Ophiothela-sp-1.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="149" /></a><br />
Brittle Star - Ophiothela sp</div>
</td><td style="font-size: 10pt;" width="33%"><div align="center">
<a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/brittlestars-Schlangensterne/Ophiothela-danae4.jpg" style="color: #004080;"><img alt="coral with brittle stars - Koralle mit Haarsternen" border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/brittlestars-Schlangensterne/Ophiothela-danae4.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Many snake stars (Ophiothela danae) on gorgonian</div>
</td><td style="font-size: 10pt;" width="33%"><div align="center">
<a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/brittlestars-Schlangensterne/Ophiomastix-variabilis.jpg" style="color: #004080;"><img alt="Black brittle star (Ophiomastix variabilis)" border="0" height="198" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/brittlestars-Schlangensterne/Ophiomastix-variabilis.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="149" /></a><br />
Black brittle star (Ophiomastix variabilis)<br />
</div>
</td></tr>
<tr align="center" valign="top"><td style="font-size: 10pt;" width="33%"><div align="center">
<a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/brittlestars-Schlangensterne/Ophiarthrum-pictum1.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/brittlestars-Schlangensterne/Ophiarthrum-pictum1.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
<a href="http://www.starfish.ch/invertebrates-Wirbellose/echinoderms-Stachelhauter/Ophiarthrum-pictum.html" style="color: #004080;">INFO</a> - Serpent star (Ophiarachna incrassata)</div>
</td><td style="font-size: 10pt;" width="33%"><div align="center">
<a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/brittlestars-Schlangensterne/Astroboa-ernae.jpg" style="color: #004080;"><img alt="Erna's basket star (Astroboa ernae)" border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/brittlestars-Schlangensterne/Astroboa-ernae.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Erna's basket star (Astroboa ernae)</div>
</td><td style="font-size: 10pt;" width="33%"><div align="center">
<a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/brittlestars-Schlangensterne/Astroglymma-sculptum1.jpg" style="color: #004080;"><img border="0" height="198" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/brittlestars-Schlangensterne/Astroglymma-sculptum1.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="149" /></a><br />
Basket star (Astroglymma sculptum)</div>
</td></tr>
</tbody></table>
<div align="center">
<img height="3" src="http://www.starfish.ch/image/bars/Abar-korallenriff.gif" style="border-color: rgb(0, 0, 0);" width="100%" /></div>
</td></tr>
<tr><td style="font-size: 10pt;" valign="top"><h5>
<a href="" name="urchin"></a><span style="color: blue;">Sea urchin</span></h5>
(Echinoidea)<br />
<div align="center">
<img alt="Seeigel" height="100" src="http://www.starfish.ch/Zeichnung/Illustrationen/c-Seeigel.gif" style="border-color: rgb(0, 0, 0);" width="132" /></div>
<h5>
</h5>
</td><td style="font-size: 10pt;" valign="top"> </td><td style="font-size: 10pt;" valign="top"><h4>
<span style="color: #0066ff;">Characteristics of sea urchins</span></h4>
Radial symmetrical body with a external chitinous skeleton and a centrally located jaw (called Aristotle's lantern) with horny teeth. The mouth consists of a complex arrangement of muscles and plates surrounding the circular opening. The anus is located on the upper surface. Some sea urchins have a spherical, bulb like cloaca (to store fecal material) that protrudes from the anal opening. It can be withdrawn into the shell.<br />
Depending on the species, movable spines of various sizes and forms are attached to the body. These spines often are sharp, pointed and in some cases even venomous. Pincer like pedicellaria for grabbing small prey. Some pedicellaria are also poisonous.<br />
<h4>
<span style="color: #0066ff;">Ecology and range of sea urchins</span></h4>
Rubble and sand. An abundance of sea urchins can be a sign for bad water conditions.<br />
<h4>
<span style="color: #0066ff;">Behavior of sea urchins</span></h4>
Locomotion by tube feet but also by movement of the spines on the underside of the body. Sea urchins are generally nocturnal, during the day they hide in crevices. However some sea urchins such as Diadema sometimes form large aggregations in open exposed areas. Despite their sharp spines sea urchins are easy game for some fishes, particularly triggerfishes and puffers. A triggerfish grabs the sea urchin with its hard beak like mouth by the spines or it blows some water towards the sea urchin and turns it on its back. The underside of a sea urchin has much shorter spines and those are easily crushed. During the breeding season the body cavity is crammed with eggs or sperms. This is one of the main reasons urchins are so attractive to fish predators (Japanese also like them for the same reason).</td></tr>
<tr><td style="font-size: 10pt;" valign="top"><div align="center">
</div>
</td><td style="font-size: 10pt;" valign="top"> </td><td style="font-size: 10pt;" valign="top">Some sea urchins are camouflaged. They hold on with their tube feet onto some bottom debris like rubble or pieces of seagrass and carry them on their back. Some even carry live soft corals or anemones.<br />
Most sea urchins are algal grazers but some feed on sponges, bryozonans and ascidians and others on detritus (detritus = organically enriched film that covers rocks).<br />
The sexes are separate and the young are formed indirectly by the fusion of sperm and eggs released into the water.</td></tr>
<tr><td style="font-size: 10pt;" valign="top"><h5>
<a href="" name="cardninalfish"></a><span style="color: blue;">Sea urchin cardinalfish</span></h5>
(Siphamia versicolor)<br />
<h5>
<a href="" name="shrimpfish"></a><span style="color: blue;">Shrimpfish</span></h5>
Aeoliscus strigatus - Centriscidae)<br />
<h5>
<a href="" name="shrimp"></a><span style="color: blue;">Sea urchin shrimp</span></h5>
<div align="left">
(Stegopontonia commensalis)</div>
<h5 align="left">
<span style="color: blue;">Mandarinfish, dragonet</span></h5>
(Synchiropus splendidus)<h5>
</h5>
</td><td style="font-size: 10pt;" valign="top"> </td><td style="font-size: 10pt;" valign="top">Many animals live in symbiotic relation with sea urchins. Even on the poisonous spines of the fire urchin (Asthenosoma varium) small shrimps (Periclimenes colemani) can be found. One shrimp<span style="font-size: x-small;"> (Stegopontonia commensalis)</span> is striped black and white lengthwise and perfectly camouflaged and lives in spines of the long-spined sea urchin (Diadema setosum). Some cardinalfishes and juvenile shrimpfishes also like to take shelter in-between these spines, but even small cuttlefish hide there. It has been observed, that they change their coloring also to black and white. Some flatworms wrap around the thicker spines of the diadema sea urchin (Echinothrix calamaris).<br />
<div align="center">
<img alt="hidden razor fish" height="189" src="http://www.starfish.ch/Zeichnung/Illustrationen/Schnepfenmesserfisch.GIF" style="border-color: rgb(0, 0, 0);" width="168" /> <img alt="Garnele versteckt sich zwischen Stacheln" height="199" src="http://www.starfish.ch/Zeichnung/Illustrationen/SeeigelundGarnele.gif" style="border-color: rgb(0, 0, 0);" width="141" /></div>
The mandarin dragonet (Mandarinfish) lives close to congregations of sea urchins and hides among them if threatened.<br />
There are two specialized types of sea urchins with an unusual appearance: the sand dollar is very much flattened with very small spines and the heart urchin which are oval and have bristle like spines. The both bury in sand. The heart urchin "jumps" out of the sand, when disturbed.</td></tr>
<tr><td colspan="3" style="font-size: 10pt;"><h4 align="center">
Photos of sea urchins (<a href="http://www.starfish.ch/c-invertebrates/seeigel.html" style="color: #004080;">photo collection</a>) click for enlargement</h4>
<table style="width: 100%px;"><tbody>
<tr align="center" valign="top"><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/seaurchins-Seeigel/Maretia-planulata1.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/seaurchins-Seeigel/Maretia-planulata1.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Heart Sea Urchin - Maretia planulata<br />
</td><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/seaurchins-Seeigel/Prionocidaris-verticillata.jpg" style="color: #004080;"><img alt="Sea urchin (Prionocidaris " border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/seaurchins-Seeigel/Prionocidaris-verticillata.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Sea urchin (Prionocidaris verticillata)<br />
</td><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/seaurchins-Seeigel/Astropyga-radiata.jpg" style="color: #004080;"><img alt="Sea urchin (Astropyga " border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/seaurchins-Seeigel/Astropyga-radiata.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Sea urchin (Astropyga radiata)<br />
</td></tr>
<tr align="center" valign="top"><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/seaurchins-Seeigel/Diadema-setosum2.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/seaurchins-Seeigel/Diadema-setosum2.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Sea Urchin - Diadema setosum</td><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/seaurchins-Seeigel/Toxopneustes-pileolus2.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/seaurchins-Seeigel/Toxopneustes-pileolus2.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Toxic sea urchin (Asthenosoma pileolus)<br />
</td><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/seaurchins-Seeigel/Echinometra-mathaei.jpg" style="color: #004080;"><img alt="Matha's sea urchin (Echinometra mathaei)" border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/seaurchins-Seeigel/Echinometra-mathaei.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Matha's sea urchin (Echinometra mathaei)</td></tr>
<tr><td align="center" style="font-size: 10pt;" valign="top" width="33%"><a href="http://www.starfish.ch/Fotos/crustaceans-Gliederfuesser/true-crabs-Krabben/Zebrida-adamsii4.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/crustaceans-Gliederfuesser/true-crabs-Krabben/Zebrida-adamsii4.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Zebracrab (Zebrida adamsii) on sea urchin</td><td align="center" style="font-size: 10pt;" valign="top" width="33%"><a href="http://www.starfish.ch/Fotos/crustaceans-Gliederfuesser/shrimps-Garnelen/Stegopontonia-commensalis3.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/crustaceans-Gliederfuesser/shrimps-Garnelen/Stegopontonia-commensalis3.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
shrimp (Stegopontonia commensalis)<br />
</td><td align="center" style="font-size: 10pt;" valign="top" width="33%"><a href="http://www.starfish.ch/Fotos/crustaceans-Gliederfuesser/shrimps-Garnelen/Periclimenes-colemani1.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/crustaceans-Gliederfuesser/shrimps-Garnelen/Periclimenes-colemani1.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Coleman shrimp (Periclimenes colemani)</td></tr>
<tr><td align="center" style="font-size: 10pt;" valign="top" width="33%"><a href="http://www.starfish.ch/Fotos/comb-jellies-Rippenquallen/Coeloplana-sp3-1.jpg" style="color: #004080;"><img border="0" height="198" src="http://www.starfish.ch/Fotos/thumbnail/comb-jellies-Rippenquallen/Coeloplana-sp3-1.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="149" /></a><br />
Comb yellies on seeurchin - Coeloplana</td><td align="center" style="font-size: 10pt;" valign="top" width="33%"><a href="http://www.starfish.ch/photos/fishes-Fische/shrimpfishes-Schnepfenmesserfische/Centriscus-scutatus.jpg" style="color: #004080;"><img border="0" height="198" src="http://www.starfish.ch/photos/thumbnail/fishes-Fische/shrimpfishes-Schnepfenmesserfische/Centriscus-scutatus.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="149" /></a><br />
Shrimpfish (Aeoliscus strigatu)<br />
</td><td align="center" style="font-size: 10pt;" valign="top" width="33%"><a href="http://www.starfish.ch/photos/fishes-Fische/clingfishes-Schildbauch/Diademichthys-lineatus3.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/photos/thumbnail/fishes-Fische/clingfishes-Schildbauch/Diademichthys-lineatus3.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Urchin clingfish - Diademichthys lineatus</td></tr>
</tbody></table>
<div align="center">
<img height="3" src="http://www.starfish.ch/image/bars/Abar-korallenriff.gif" style="border-color: rgb(0, 0, 0);" width="100%" /></div>
</td></tr>
<tr><td style="font-size: 10pt;" valign="top"><h5>
<a href="" name="cucumber"><span style="color: blue;">Holothurians</span></a><a href="" name="holothurian"></a></h5>
(Holothuroidea)<br />
<div align="center">
<img alt="zwei Seewalzen" height="126" src="http://www.starfish.ch/Zeichnung/Illustrationen/c-Seewalze1.gif" style="border-color: rgb(0, 0, 0);" width="177" /></div>
<div align="center">
<img alt="Seewalze" height="71" src="http://www.starfish.ch/Zeichnung/Illustrationen/c-Seewalze.gif" style="border-color: rgb(0, 0, 0);" width="172" /></div>
</td><td style="font-size: 10pt;" valign="top"> </td><td style="font-size: 10pt;" valign="top"><h4>
<span style="color: #0066ff;">Characteristics of sea cucumbers</span></h4>
Unlike other echinoderms, holothurians don't have a distinct radial symmetry but are bilateral (distinct dorsal and ventral side). Holothurians are also called sea cucumbers. As their name suggests, they are cucumber shaped with an elongated, muscular, flexible body with a mouth at one end and the anus at the other. Around the mouth there is a number of tentacles (modified tube feet) used in food collecting. Sea cucumbers come in many sizes, from small species only a few centimeter in length to long snakelike animals which may stretch up to 2 meter!<br />
<h4>
<span style="color: #0066ff;">Ecology and range of sea cucumbers</span></h4>
Rubble, rocks and sand. Also seen on some sponges in large aggregations.<br />
<h4>
<span style="color: #0066ff;">Behavior of sea cucumbers</span></h4>
Most species feed on the rich organic film coating sandy surfaces. The crawl over the bottom ingesting sand. The edible particles (organic matter such as plankton, foraminifera and bacteria) are extracted when passing through their digestive tract and the processed sand is expelled from the anus (as worm-like excrements).<br />
Sea cucumbers move by means of tube feet which extend in rows from the underside of the body. The tentacles surrounding the mouth are actually tube feet that have been modified for feeding.<br />
Other holothurians feed on current-borne zooplankton. They bury in sand extruding their featherlike tentacles (Pseudocolochirus violaceus, Neothyondium magnum or Pentacta crassa). The tentacles have the same shape as soft corals or some anenemones. Large congregations of some small species are found on sponges. They apparently feed on substances secreted by the sponges as well as detritus from the surface.<br />
Some species of holothurians have separate sexes others are hermaphrodites. The sea cucumbers hold on to exposed rocks or corals, raise their body to a upright position, rock back and forth and release the sperm and eggs into the sea.</td></tr>
<tr><td style="font-size: 10pt;" valign="top"><div align="center">
</div>
</td><td style="font-size: 10pt;" valign="top"> </td><td style="font-size: 10pt;" valign="top">Sea cucumbers have a remarkable capacity for regenerating their body parts. When attacked they shed a sticky thread like structure which is actually parts of their guts. The so called Cuverian threads are toxic (the poison is called holothurin) and can dissuade many potential predators. These structures quickly regenerate. (see photos below)</td></tr>
<tr><td style="font-size: 10pt;" valign="top"><h5>
<a href="" name="pearlfish"><span style="color: blue;">Pearlfish</span></a></h5>
<span style="font-size: x-small;">(Carapidae)</span><br />
<span style="font-size: x-small;">Encheliophis homei and mourlani</span> / Onuxodon margaritiferae</td><td style="font-size: 10pt;" valign="top"> </td><td style="font-size: 10pt;" valign="top">Holothurians host a variety of symbiotic organisms: crabs, shrimps, worms and even a very unusual fish. The pearlfish <span style="font-size: x-small;">(Encheliophis homei and mourlani</span> / Onuxodon margaritiferae) has a long slender, transparent body and lives in the gut cavity of the sea cucumber (Boshida argus, Thelanota ananas, Stichopus chloronotus). They also inhabit some starfish as well as pearl oyster shells. The fish leaves and enters (tail first) through the holothurian's anus. They probably feed on the gonads and other tissues of its host. It is said to leave at night to feed on small fishes and shrimps. Sea cucumbers are used in Asia as a base for soups.</td></tr>
<tr><td colspan="3" style="font-size: 10pt;"><h4 align="center">
Photos of sea cucumbers (<a href="http://www.starfish.ch/c-invertebrates/seewalzen.html" style="color: #004080;">photo collection</a>) click for enlargement</h4>
<table style="width: 100%px;"><tbody>
<tr align="center" valign="top"><td style="font-size: 10pt;"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Bohadschia-argus-cuvierian.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Bohadschia-argus-cuvierian.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Sea cucumber (Bohadschia argus) with Cuiverian threads</td><td style="font-size: 10pt;"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Bohadschia-argus.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Bohadschia-argus.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Sea cucumber (Bohadschia argus) with Cuiverian threads<br />
</td><td style="font-size: 10pt;"><a href="http://www.starfish.ch/Fotos/crustaceans-Gliederfuesser/shrimps-Garnelen/Periclimenes-imperator8.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/crustaceans-Gliederfuesser/shrimps-Garnelen/Periclimenes-imperator8.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
<a href="http://www.starfish.ch/invertebrates-Wirbellose/crustaceans-Gliederfuesser/Periclimenes-imperator.html" style="color: #004080;">INFO</a> - Emperor Shrimp on Sea Cucumber - Periclimenes imperator on Opheodesoma australiensis</td></tr>
<tr align="center" valign="top"><td style="font-size: 10pt;" width="33%"><div align="center">
<a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Holothuria-atra1.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Holothuria-atra1.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a></div>
<div align="center">
Black Sea Cucumber - Holothuria atra</div>
<br />
</td><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Thelenota-ananas4.jpg" style="color: #004080;"><img alt="Pineapple sea cucumber (Thelenota ananas)" border="0" height="198" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Thelenota-ananas4.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="149" /></a><br />
Pineapple sea cucumber (Thelenota ananas) - <a href="http://www.starfish.ch/invertebrates-Wirbellose/echinoderms-Stachelhauter/Thelenota-ananas.html" style="color: #004080;">gallery</a><br />
</td><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Synaptula-media1.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Synaptula-media1.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
<a href="http://www.starfish.ch/invertebrates-Wirbellose/echinoderms-Stachelhauter/Synaptula-media.html" style="color: #004080;">INFO</a> - Sea Cucumber - Synaptula media</td></tr>
<tr align="center" valign="top"><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Synapta-maculata3.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Synapta-maculata3.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Sea Cucumber details tentacles (Synapta maculata)</td><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Thelenota-rubralineata.jpg" style="color: #004080;"><img alt="Sea cucumber skin (Thelenota " border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Thelenota-rubralineata.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Sea cucumber skin (Thelenota rubrolineata)</td><td style="font-size: 10pt;" width="33%"><a href="http://www.starfish.ch/Fotos/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Stichopus-horrens2.jpg" style="color: #004080;"><img border="0" height="149" src="http://www.starfish.ch/Fotos/thumbnail/echinoderms-Stachelhauter/seacucumbers-Seewalzen/Stichopus-horrens2.jpg" style="border-color: rgb(0, 0, 0); color: black;" width="198" /></a><br />
Horrid Sea Cucumber - Stichopus horrens</td></tr>
</tbody></table>
</td></tr>
</tbody></table>
Anonymoushttp://www.blogger.com/profile/15125980005528241488noreply@blogger.com0tag:blogger.com,1999:blog-407184866172719703.post-35490113737534730512012-10-16T08:16:00.001-07:002012-10-16T08:16:45.022-07:00Phylum Mollusca (6th Phylum)<br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">The largest marine phylum, having around 93,000 species, molluscs have a great variety in terms of their anatomy, habitat and behavior. Most of the molluscs are categorized under the class 'gastropoda'. The major gastropods are snails and slugs. The word mollusc is derived from the French, 'mollusque'. This French word too was derived from the Latin word molluscus which means 'soft'. The important phylum mollusca habitats are oceans and freshwater. These are important creatures of the marine biome. Some of these creatures are however, terrestrial in nature. Let us have a look at various phylum mollusca characteristics in the following article.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;"><br /></span></span>
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">Different Traits of Phylum Mollusca</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;"><br /></span></span>
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">Snails, clams and squids are important phylum mollusca examples. The phylum mollusca facts related to anatomy, physiology and other features are enlisted in the paragraphs below.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;"><br /></span></span>
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">Anatomical Characteristics of Molluscs</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">The anatomy/structure of molluscs are complex in nature. One of the special features of their body structure is the presence of a coelom. The coelom is a cavity present in body of molluscs and which contains internal organs suspended from mesenteries. Let us find out more information about the anatomical characteristics of molluscs.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">The upper surface of molluscs is covered by a shell formed from secretions of mantle. A muscular foot is present on underside of the body.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">The mantle cavity is a body part of molluscs formed by the fold produced in the mantle. Position of the mantle varies from one species to other.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">Different organs present in the mantle cavity include the reproductive organs (gonads), gills, kidneys (nephridia) and the anus. The anus is formed of chemical sensors called osphradia.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">The shells of molluscs are formed of calcium carbonate (95%) and organic components (1%). Biomineralization is a special feature of mollusc shells which give them the necessary strength.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">The feet of the molluscs carry out different functions in different classes. A balance organ called statocyst is incorporated in the foot structure of molluscs.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">In limpets, the foot is modified into a sucker which helps in anchoring the animal to hard surfaces.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">The foot in the gastropods secrete mucus to facilitate movement.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">Physiological Characteristics of Molluscs</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">The facts presented below reveal interesting information about the characteristics of phylum mollusca that are physiological in nature.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;"><br /></span></span>
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">Locomotion</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">There is great diversity among molluscs in terms of locomotory organs. Most of the molluscs move from one place to other by means of muscular contraction. The herbivorous species glide over waves of water. The undulating lateral fins of the cuttlefish enables it to move by performing maneuvers. A jet propulsion technique is used by cephalopods for swimming rapidly in water.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;"><br /></span></span>
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">Digestive and Excretory Functions</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">The stomach of molluscs are complicated in structure. The mouth and the anus form the parts of digestive and excretory system; these parts are connected to each other by the complex stomach. The entire digestive tract is lined by cilia. Absorption of food from the digestive tract is done by cells aligned with digestive glands in the stomach; nutrients absorbed from this food, then enter the blood. Waste or undigested materials are excreted through the anus. The waste materials before excretion are compressed and packaged in a solid form; before reaching the anus these undigested materials are stored in the mantle cavity.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;"><br /></span></span>
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">Phylum Mollusca Reproduction</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">Reproduction of molluscs takes place by means of external fertilization, through which eggs are produced. There is a lot of variation in types of larvae that emerge from eggs. Larvae could be the trochopore, veliger or in some cases even miniature adults are produced directly.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;"><br /></span></span>
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">Nervous and Sensory System of Molluscs</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">Molluscs have a highly developed nervous system which varies from species to species. The octopus has such a complex and intelligent brain that its mental abilities match that of a domestic cat. Thus, it is deemed as the most intelligent invertebrate. Squids are capable of locating transparent creatures by means of polarized vision. The giant squid is known to have biggest eyes in the entire animal kingdom.</span></span><br />
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;"><br /></span></span>
<span style="font-family: Verdana, Arial, sans-serif;"><span style="font-size: 12px; line-height: 18px;">There is a lot to say about these sea creatures, the molluscs. Variety in their forms, body features, etc. has been studied to reveal interesting information about molluscs. The phylum mollusca characteristics presented above thus, provides brief information about these creatures.</span></span><br />
<div>
<div>
The largest marine phylum, having around 93,000 species, molluscs have a great variety in terms of their anatomy, habitat and behavior. Most of the molluscs are categorized under the class 'gastropoda'. The major gastropods are snails and slugs. The word mollusc is derived from the French, 'mollusque'. This French word too was derived from the Latin word molluscus which means 'soft'. The important phylum mollusca habitats are oceans and freshwater. These are important creatures of the marine biome. Some of these creatures are however, terrestrial in nature. Let us have a look at various phylum mollusca characteristics in the following article.</div>
<div>
<br /></div>
<div>
Different Traits of Phylum Mollusca</div>
<div>
<br /></div>
<div>
Snails, clams and squids are important phylum mollusca examples. The phylum mollusca facts related to anatomy, physiology and other features are enlisted in the paragraphs below.</div>
<div>
<br /></div>
<div>
Anatomical Characteristics of Molluscs</div>
<div>
The anatomy/structure of molluscs are complex in nature. One of the special features of their body structure is the presence of a coelom. The coelom is a cavity present in body of molluscs and which contains internal organs suspended from mesenteries. Let us find out more information about the anatomical characteristics of molluscs.</div>
<div>
The upper surface of molluscs is covered by a shell formed from secretions of mantle. A muscular foot is present on underside of the body.</div>
<div>
The mantle cavity is a body part of molluscs formed by the fold produced in the mantle. Position of the mantle varies from one species to other.</div>
<div>
Different organs present in the mantle cavity include the reproductive organs (gonads), gills, kidneys (nephridia) and the anus. The anus is formed of chemical sensors called osphradia.</div>
<div>
The shells of molluscs are formed of calcium carbonate (95%) and organic components (1%). Biomineralization is a special feature of mollusc shells which give them the necessary strength.</div>
<div>
The feet of the molluscs carry out different functions in different classes. A balance organ called statocyst is incorporated in the foot structure of molluscs.</div>
<div>
In limpets, the foot is modified into a sucker which helps in anchoring the animal to hard surfaces.</div>
<div>
The foot in the gastropods secrete mucus to facilitate movement.</div>
<div>
Physiological Characteristics of Molluscs</div>
<div>
The facts presented below reveal interesting information about the characteristics of phylum mollusca that are physiological in nature.</div>
<div>
<br /></div>
<div>
Locomotion</div>
<div>
There is great diversity among molluscs in terms of locomotory organs. Most of the molluscs move from one place to other by means of muscular contraction. The herbivorous species glide over waves of water. The undulating lateral fins of the cuttlefish enables it to move by performing maneuvers. A jet propulsion technique is used by cephalopods for swimming rapidly in water.</div>
<div>
<br /></div>
<div>
Digestive and Excretory Functions</div>
<div>
The stomach of molluscs are complicated in structure. The mouth and the anus form the parts of digestive and excretory system; these parts are connected to each other by the complex stomach. The entire digestive tract is lined by cilia. Absorption of food from the digestive tract is done by cells aligned with digestive glands in the stomach; nutrients absorbed from this food, then enter the blood. Waste or undigested materials are excreted through the anus. The waste materials before excretion are compressed and packaged in a solid form; before reaching the anus these undigested materials are stored in the mantle cavity.</div>
<div>
<br /></div>
<div>
Phylum Mollusca Reproduction</div>
<div>
Reproduction of molluscs takes place by means of external fertilization, through which eggs are produced. There is a lot of variation in types of larvae that emerge from eggs. Larvae could be the trochopore, veliger or in some cases even miniature adults are produced directly.</div>
<div>
<br /></div>
<div>
Nervous and Sensory System of Molluscs</div>
<div>
Molluscs have a highly developed nervous system which varies from species to species. The octopus has such a complex and intelligent brain that its mental abilities match that of a domestic cat. Thus, it is deemed as the most intelligent invertebrate. Squids are capable of locating transparent creatures by means of polarized vision. The giant squid is known to have biggest eyes in the entire animal kingdom.</div>
<div>
<br /></div>
<div>
There is a lot to say about these sea creatures, the molluscs. Variety in their forms, body features, etc. has been studied to reveal interesting information about molluscs. The phylum mollusca characteristics presented above thus, provides brief information about these creatures.</div>
</div>
Anonymoushttp://www.blogger.com/profile/15125980005528241488noreply@blogger.com1tag:blogger.com,1999:blog-407184866172719703.post-27695025834998597562012-10-16T08:10:00.001-07:002012-10-16T08:10:21.016-07:00Phylum Annelida (5th Phylum)<br />
<h3 style="background-color: white; font-family: Arial, Helvetica, sans-serif; font-size: 12px; font-weight: normal; margin: 0px; padding: 0px; text-align: justify;">
<ul style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<li>Free-living, terrestrial or aquatic form (freshwater or marine).</li>
</ul>
<ul style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<li>Body is long, cylindrical and metamerically segmented.</li>
</ul>
<ul style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<li>Body wall consists of cuticle, epidermis and musculature.</li>
</ul>
<ul style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<li>Body cavity is a true coelom, lined by epithelium.</li>
</ul>
<ul style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<li>Digestive system is complete.</li>
</ul>
<ul style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<li>Respiration is either through skin or through gills.</li>
</ul>
<ul style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<li>Excretion with the help of characteristic nephridia.</li>
</ul>
<ul style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<li>Presence of a circulatory system (closed type). Hemoglobin dissolved directly in the plasma.</li>
</ul>
<ul style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<li>Nervous system consists of a nerve ring and a double ventral nerve cord with segmental ganglia.</li>
</ul>
<ul style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<li>Locomotion with the help of setae or parapodia.</li>
</ul>
<ul style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<li>Reproduction by sexual methods. Either unisexual or bisexual development may be direct or indirect.</li>
</ul>
<ul style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<li>Body has a true coelom.</li>
</ul>
<div style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<img align="middle" alt="" height="302" src="http://images.tutorvista.com/content/animal-kingdom/phylum-annelida.jpeg" style="border: 0px;" width="352" /></div>
<div style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
fig. 10.13 - Examples of Annelida</div>
<div style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
The phylum is divided into four classes</div>
<table align="left" border="1" cellpadding="3" cellspacing="0" style="border-collapse: collapse; color: black; font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start; width: 100%px;"><thead>
<tr><th align="left" scope="col"> Characteristics</th><th align="left" scope="col"> Class Polychaeta</th><th align="left" scope="col"> Class Oligochaeta</th><th align="left" scope="col"> Class Hirudinea</th><th align="left" scope="col"> Class Archi annelida</th></tr>
</thead><tbody>
<tr><td align="left"> Habit and habitat</td><td align="left"> Free living marine</td><td align="left"> Free living forms found in most soil</td><td align="left"> Fresh water forms Temporary ectoparasites</td><td align="left"> Marine forms</td></tr>
<tr><td align="left"> Locomotor Structure</td><td align="left"> Parapodia</td><td align="left"> Setae</td><td align="left"> Absent</td><td align="left"> Absent</td></tr>
<tr><td align="left"> Lifecyle</td><td align="left"> Unisexual with indirect development</td><td align="left"> Bisexual with direct development</td><td align="left"> Bisexual with direct development</td><td align="left"> Bisexual with indirect development</td></tr>
<tr><td align="left"> Examples</td><td align="left"> Nereis (reg worm)</td><td align="left"> Pheretima, Megasolex (earth worms)</td><td align="left"> Hirudinaria (leech)</td><td align="left"> Polygrdius</td></tr>
</tbody></table>
<div style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<img align="middle" alt="" height="158" src="http://images.tutorvista.com/content/animal-kingdom/nereis-structure.jpeg" style="border: 0px;" width="227" /></div>
<div style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
fig. 10.14 - Anterior Segments of Nereis</div>
<div style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
<img align="middle" alt="" height="301" src="http://images.tutorvista.com/content/animal-kingdom/earthworm-anatomy.jpeg" style="border: 0px;" width="375" /></div>
<div style="font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start;">
fig. 10.15 - Earthworm Anatomy</div>
</h3>
<div>
<br /></div>
Anonymoushttp://www.blogger.com/profile/15125980005528241488noreply@blogger.com0tag:blogger.com,1999:blog-407184866172719703.post-2343622575513945322012-10-16T08:00:00.002-07:002012-10-16T08:00:39.981-07:00Phylum Nematoda (4th Phylum)<br />
There are thousands of nematodes. Not only are there more than 15,000 known species of roundworms, but there are many thousands of individual nematodes in even a single handful of garden soil. And they keep coming! Some species of roundworm may contain more than 27 million eggs at one time and lay more than 200,000 of them in a single day. Some scientists have estimated that there may be as many as half a million more unkown species of roundworm yet to be discovered, an estimate based on the fact that many new species are still being discovered, that relatively few people are looking for more species, and that most roundworms look pretty much alike. If the estimated number of species is anywhere close to correct, it would mean that roundworms are the second most diverse group of animals, trailing behind only the arthropods.<br />
Nematodes were once classified with a very large and heterogeneous cluster of <a href="http://www.ucmp.berkeley.edu/phyla/phyla.html">animals</a> grouped together on the basis of their overall worm-like appearance, simple structure of an internal body cavity called a<b>pseudocoelom</b>, and the lack of features such as cilia and a well-defined head that are found in most animals. This group, variously known as Aschelminths or Pseudocoelomata, is today no longer recognized as a natural one. It is quite likely that the simple body plan of these organisms has resulted from reduction and simplification from more than one group of ancestral organisms, and so the pseudocoelom is neither a uniquely derived nor useful character. (Wallace, Ricci, & Malone 1996) The simplicity is thus a result of secondary simplification from a more complex body design, and not necessarily an indication of primitive or simple origins. Current studies indicate that nematodes are actually related to the <a href="http://www.ucmp.berkeley.edu/arthropoda/arthropoda.html">arthropods</a> and <a href="http://www.ucmp.berkeley.edu/phyla/ecdysozoa/cephalorhyncha.html">priapulids</a> in a newly recognized group, the <span style="color: black;"><a href="http://www.ucmp.berkeley.edu/phyla/ecdysozoa.html">Ecdysozoa</a>.</span><br />
<br />
<center>
<hr width="85%" />
<table border="0" cellpadding="0" cellspacing="10"><tbody>
<tr><td><a href="http://www.ucmp.berkeley.edu/phyla/ecdysozoa/nematode.jpg"><span style="color: black;"><img alt="nematode micrograph" border="0" height="275" src="http://www.ucmp.berkeley.edu/phyla/ecdysozoa/nematodesm.jpg" width="260" /></span></a></td><td><a href="http://www.ucmp.berkeley.edu/phyla/ecdysozoa/nematodexs.gif"><span style="color: black;"><img alt="Nematode cross-section" border="0" height="275" src="http://www.ucmp.berkeley.edu/phyla/ecdysozoa/nematodexssm.gif" width="350" /></span></a></td></tr>
</tbody></table>
</center>
<blockquote>
<span><b>Roundworms :</b> The image at left shows a living microscopic roundworm as viewed with an Environmental SEM. The worm is approximately one millimeter long. At right, a diagrammatic view of the internal anatomy of a roundworm, showing the simplicity of its organization. See text below for discussion. (Click on either of the pictures above for a larger image).</span></blockquote>
<hr width="85%" />
The body of a nematode is long and narrow, resembling a tiny thread in many cases, and this is the origin of the group's name. The word "nematode" comes from a Greek word <i>nema</i> that means "thread". The<b>epidermis</b> (skin) of a nematode is highly unusual; it is not composed of cells like other animals, but instead is a mass of cellular material and nuclei without separate membranes. This epidermis secretes a thick outer <b>cuticle</b> which is both tough and flexible. The cuticle is a feature shared with <a href="http://www.ucmp.berkeley.edu/arthropoda/arthropoda.html">arthropods</a> and other <a href="http://www.ucmp.berkeley.edu/phyla/ecdysozoa.html">ecdysozoans</a>. As in those other groups, the cuticle is periodically shed during the life of a nematode as it grows, usually four times before reaching the adult stage. The cuticle is the closest thing a roundworm has to a skeleton, and in fact the worm uses its cuticle as a support and leverage point for movement. Long <b>muscles</b> lie just underneath the epidermis. These muscles are all aligned longitudinally along the inside of the body, so the nematode can only bend its body from side to side, not crawl or lift itself. A free-swimming roundworm thus looks rather like it is thrashing about aimlessly.<br />
The muscles are activated by two <b>nerves</b> that run the length of the nematode on both the dorsal (back) and ventral (belly) side. Unlike other animals, where the nerves branch out to the muscle cells, a nematode's muscle cells branch toward the nerves. The <b>ventral nerve</b> has a series of nerve centers along its length, and both nerves connect to a nerve ring and additional nerve centers located near the head.<br />
The head of a nematode has a few tiny sense organs, and a mouth opening into a muscular <b>pharynx</b> (throat) where food is pulled in and crushed. This leads into a long simple gut cavity lacking any muscles, and then to an anus near the tip of the body. Food digested in the gut is not distributed by any specialized vascular system, and neither is there a respiratory system for the uptake or distribution of oxygen. Rather, nutrients and waste are distributed in the body cavity, whose contents are regulated by an <b>excretory canal</b> along each side of the body.<br />
Many nematodes are able to suspend their life processes completely when conditions become unfavorable; in these resistant states they can survive extreme drying, heat, or cold, and then return to life when favorable conditions return. This is known as <b>cryptobiosis</b>, and is a feature nematodes share with <a href="http://www.ucmp.berkeley.edu/phyla/rotifera/rotifera.html">rotifers</a> and <b>tardigrades</b>.<br />
Fossil nematodes have been found in rocks from as early as the <a href="http://www.ucmp.berkeley.edu/carboniferous/carboniferous.html">Carboniferous</a>. Most living roundworms are microscopic, meaning that their discovery as fossils is likely to be difficult. On the other hand, one species of parasitic nematode can reach 13 meters in length -- it parasitizes the sperm whale. Nematodes also lack any substantial hard parts, again resulting in a spotty chance for fossilization. Despite these problems, fossil nematodes are occasionally found in amber (fossilized tree resin) from the <a href="http://www.ucmp.berkeley.edu/cenozoic/cenozoic.html">Cenozoic</a>. Because many of their relatives have left fossils dating from the <a href="http://www.ucmp.berkeley.edu/cambrian/camb.html">Cambrian</a>, it is likely that the nematodes have been around at least that long in some form.<br />
If you've wandered around our exhibits much, you've seen many groups described as living just about anywhere. That statement goes triple for nematodes, who live not only in almost every geographic location on Earth, but live in such extreme habitats as ice and hot springs, as well as living on or in almost every other kind of animal and plant alive today. Free-living nematodes are extremely abundant in soils and sediments, where they feed on bacteria and detritus. Other nematodes are plant parasites and may cause disease in economically important crops. Still others parasitize animals (including humans); well-known parasitic nematodes include hookworms, pinworms, Guinea worm (genus <i>Dracunculus</i>), and intestinal roundworms (genus <i>Ascaris</i>).<br />
Anonymoushttp://www.blogger.com/profile/15125980005528241488noreply@blogger.com0tag:blogger.com,1999:blog-407184866172719703.post-7474242584566334302012-10-16T07:56:00.001-07:002012-10-16T07:56:06.428-07:00Phylum Platyhelmithes (3rd Phylum)<br />
Lowest of the worms are Platyhelminthes. The have thin soft bodies. This phylum includes three classes:<br />
Turbellaria (free-living flatworms) most of which enhabit fresh water, saltwater or moist places on land.<br />
Trematoda (flukes). External or internal parasites.<br />
Cestoda (Tapeworms) the adults of which are intestinal parasites of vertebrates.<br />
Some of these parasites cause serious illness or death to their hosts.<br />
<br />
<br />
Characteristics:<br />
<br />
1. Symmetry bilateral. Three germ layers (triploblastic). Body usually flattened dorsoventrally. No true segmentation.<br />
<br />
2. Epidermis soft and ciliated(turbelaria), or covered with cuticule and with external suckers or hooks, or both for connection to host (Trematoda, Cestoda).<br />
<br />
3. Digestive system incomplete (a mouth but no anus) and usually much branched. None in Acoela or Cestoda.<br />
<br />
4. Muscle layers well developed. No body cavity. Spaces between internal organs filled by loose parenchyma.<br />
<br />
5. No skeletal, ciculatory or respiratory systems. Excretory system with many flame cells connected to excretory ducts (protonephridia).<br />
<br />
6. The nervous system is a pair of anterior ganglia or a nerve ring connected to 1 - 3 pairs of longitudinal nerve chords with transverse commissures.<br />
<br />
7. The sexes are usually united (monoecious). Reproductive system of each sex with gonads, ducts, and accessory organs. Fertilization occurs internally. The eggs are microscopic, each enclosed with several yolk cells in a shell. The development in its life cycle is either direct (some Turbellaria and monogenetic Trematoda) or with one or more larval stages (digenetic Trematoda and some Turbellaria and Cestoda). Asexual in some species.<br />
<br />
<br />
Only Turbellaria (free-living flatworms) are dealt with here.<br />
<table><tbody>
<tr><td height="60" width="30"></td><td><br /></td><td></td><td><br /></td><td><br /></td></tr>
</tbody></table>
<br /><table><tbody>
<tr><td width="30"></td><td>Flatworms have simple, flattened, leaf-like bodies and glide along on a bed of fine hairs or by ripples of contracting muscles.<br /><br /><table><tbody>
<tr><td><img alt="A marine flatworm with tenacles." border="0" height="357" src="http://library.thinkquest.org/26153/marine/sketch/623a.jpg" width="283" /></td></tr>
<tr><td><i><b>A marine flatworm with tenacles.</b></i></td></tr>
</tbody></table>
<br /><br />A flexible tubular proboscis traps prey such as small crustaceans and molluscs. The digestive canal ends blindly without any anus.<br /></td></tr>
</tbody></table>
<table><tbody>
<tr><td><img alt="Cross section of the body at the level of the pharynx." border="0" height="349" src="http://library.thinkquest.org/26153/marine/sketch/624.jpg" width="606" /></td></tr>
<tr><td><i><b>Cross section of the body at the level of the pharynx.</b></i></td></tr>
</tbody></table>
<br style="color: yellow;" /><table><tbody>
<tr><td><img alt="Lateral view of a generalized tuberlarian." border="0" height="210" src="http://library.thinkquest.org/26153/marine/sketch/625.jpg" width="409" /></td></tr>
<tr><td><i><b>Lateral view of a generalized tuberlarian.</b></i></td></tr>
</tbody></table>
<table><tbody>
<tr><td width="30"></td><td>Flatworms are hermafroditic, but cross fertilise. Partners then lay strings of large yolky eggs.<br /><br /><table><tbody>
<tr><td><img alt="Prostheceraeus bellostriatus : A marine flatworm. " border="0" height="162" src="http://library.thinkquest.org/26153/marine/sketch/623b.jpg" width="240" /></td></tr>
<tr><td><b><i>Prostheceraeus bellostriatus : A marine flatworm.</i></b></td></tr>
</tbody></table>
</td></tr>
</tbody></table>
Anonymoushttp://www.blogger.com/profile/15125980005528241488noreply@blogger.com0tag:blogger.com,1999:blog-407184866172719703.post-81712231716791824542012-10-16T07:50:00.001-07:002012-10-16T08:24:54.080-07:00Phylum Coelenterata/ Coelenterates (2nd Phylum)<br />
<ul style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
<li>Radially symmetrical, diploblastic multicellular animals with a tissue grade of organisation.</li>
</ul>
<ul style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
<li>Aquatic, freshwater or marine solitary or colonial forms which may be free swimming or sedentary.</li>
</ul>
<ul style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
<li>Body has a mouth at the oral end which leads into a spacious cavity called gastrovascular cavity or coelenteron.</li>
</ul>
<ul style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
<li>Presence of long, hollow structures called tentacles used for locomotion and food capturing.</li>
</ul>
<ul style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
<li>Presence of peculiar type of cells called cnidoblasts, nematocysts or stinging cells in the ectoderm, especially in the tentacles, used for offence and defence.</li>
</ul>
<ul style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
<li>Digestion is both intracellular and extracellular.</li>
</ul>
<ul style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
<li>Respiration and excretion by simple diffusion.</li>
</ul>
<ul style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
<li>Presence of a network of nerves spread all over the body.</li>
</ul>
<ul style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
<li>Many forms exhibit polymorphism, wherein different types of individuals are present in a colony for different functions. These individuals are called Zooids.</li>
</ul>
<ul style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
<li>Reproduction asexually (external budding) or sexually (formation of gametes).</li>
</ul>
<div style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
<img align="middle" height="260" src="http://images.tutorvista.com/content/animal-kingdom/phylum-coelenterata.jpeg" style="border: 0px;" width="287" /></div>
<div style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
fig. 10.7 - Examples of Coelenterata</div>
<div style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
The phylum is divided into three classes</div>
<table align="left" border="1" cellpadding="3" cellspacing="0" style="background-color: white; border-collapse: collapse; color: black; font-family: arial; font-size: 13px; line-height: 20.78333282470703px; text-align: start; width: 735px;"><thead>
<tr><th align="left" scope="col">Characteristics</th><th align="left" scope="col">Class Hydrozoa</th><th align="left" scope="col">Class Schyphozoa</th><th align="left" scope="col">Class Anthozoa</th></tr>
</thead><tbody>
<tr><td align="left">Habitat</td><td align="left">Fresh water or marine</td><td align="left">Marine</td><td align="left">Marine</td></tr>
<tr><td align="left">Body Form</td><td align="left">Polypoid or Medusoid</td><td align="left">Medusoid</td><td align="left">Polypoid</td></tr>
<tr><td align="left">Example</td><td align="left">Hydra, Obelia Physalia (Portuguese man of war)</td><td align="left">Aurelia Cassoprea (Jelly fishes)</td><td align="left">Sea anemone Astrea Fungia and other Corals</td></tr>
</tbody></table>
<div style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
<br /></div>
<div style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
<img align="middle" height="305" src="http://images.tutorvista.com/content/animal-kingdom/hydra-anatomy.jpeg" style="border: 0px;" width="447" /></div>
<div style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
fig. 10.8 - Anatomy of Hydra</div>
<div style="background-color: white; font-family: arial; font-size: 13px; line-height: 20.78333282470703px;">
</div>
<div style="background-color: white; font-family: arial; font-size: 13px; line-height: 19px; text-align: justify;">
<span style="font-size: x-small;"><span style="text-decoration: underline;"><strong>TYPES POLYMORPHIC FORMS IN CNIDARIANS: (COELENTERATA_)</strong></span></span></div>
<div style="background-color: white; font-family: arial; font-size: 13px; line-height: 19px; text-align: justify;">
<span style="font-size: x-small;"> There are three types of polymorphism (polymorphic forms) found in the Cnidarians-(<em>Obelia</em> sp.) The class Anthozoa consists only of polypoid forms.</span></div>
<div style="background-color: white; font-family: arial; font-size: 13px; line-height: 19px; text-align: justify;">
<span style="font-size: x-small;"><span style="text-decoration: underline;"><em><strong>POLYPOID FORM</strong></em><strong><em>S OF CNIDARIAN POLYMORHISM </em></strong></span><span style="text-decoration: underline;"><strong><br /></strong></span></span></div>
<ul style="background-color: white; font-family: arial; font-size: 13px; line-height: 19px;">
<li><span style="font-size: x-small;">The polypoid form or the polyp is the hydroid form, generally sessile .</span></li>
<li><span style="font-size: x-small;"> Body cylindrical hollow with a common stem of colony by proximal end .</span></li>
<li><span style="font-size: x-small;">The distal; end with a conical elevation called manubrium or oval cone with tentacles at its base in a circle.</span></li>
<li><span style="font-size: x-small;">Both body and manubrium contain coelenteron with a mouth at the top of the manubrium</span></li>
<li><span style="font-size: x-small;">.Body composed of epidermis and gastrodermis with mesoglea inbetween.</span></li>
<li><span style="font-size: x-small;">Tentacles, manibrium and polyp wall well provided with muscular cells for contraction</span></li>
<li><span style="font-size: x-small;">.Cnidoblast cells with nematocysts in tentacles <img alt="Polymorphism Coelenterata" height="399" src="http://images.tutorvista.com/content/feed/tvcs/Obelia.jpg" style="border: 0px;" title="Polymorphism Coelenterata" width="263" /><img alt="Polymorphism Coelenterata" height="395" src="http://images.tutorvista.com/content/feed/tvcs/polyp1.gif" style="border: 0px;" title="Polymorphism Coelenterata" width="298" /> <strong> </strong><em><strong>Obelia </strong></em><strong>colony </strong><strong> SIngle polyp,magified </strong><strong><br /></strong><br /> <br /> <img alt="Polymorphism Coelenterata" height="244" src="http://images.tutorvista.com/content/feed/tvcs/cnidoblast_a.gif" style="border: 0px;" title="Polymorphism Coelenterata" width="185" /> <img alt="nematocyst" height="283" src="http://images.tutorvista.com/content/feed/tvcs/Nematocyst_discharge.png" style="border: 0px;" title="nematocyst" width="367" /> <br /> <strong>CNIDOBLAST CELL</strong> <strong> DISCHARGED CNIDOBALST </strong> </span></li>
</ul>
<br />
<div style="background-color: white; font-family: sans-serif; font-size: 13px; line-height: 19.200000762939453px; margin-bottom: 0.5em; margin-top: 0.4em;">
<br /></div>
Anonymoushttp://www.blogger.com/profile/15125980005528241488noreply@blogger.com1tag:blogger.com,1999:blog-407184866172719703.post-25550812170751876542012-10-16T07:39:00.001-07:002012-10-16T07:48:12.129-07:00Phylum Porifera (1st Phylum)The Phylum Porifera contains the sponges. There are approximately 6000 sponges. Most live attached to marine reefs. Approximately 100 species live in freshwater. They lack true tissue and organs and therefore the cells are relatively unspecialised. Sponges often have complex life histories. Some species are free standing whilst others form an encrusting layer over rocks.<br />
Sponges are filter feeders. The surface of the sponge has many pores (<i>ostia</i>) through which water is drawn into the body. The water is drawn into a series of canals and chambers where food particles (plankton) are trapped. The water then passes out of the body through larger pores (<i>oscules</i>). A sponge can pump hundreds of litres through it's body each day.<br />
Being filter feeders, sponges live most successfully in areas with strong currents or wave action. They grow less rapidly than seaweeds, therefore are less common in shallow sunny reefs.<br />
A few specialised opisthobranchs (sea slugs), crustaceans, echinoderms and fish are known to feed on sponges.<br />
Most carnivorous animals avoid sponges because of the splinter-like spicules and toxic chemicals produced by the sponge.<br />
<b><u>SPONGES AT THE MDC</u></b><br />
The following species of sponge are found at the Marine Discovery Centre:<br />
<br />
<menu>
<li><b> <i>Tethya </i>sp. ? - Pumpkin sponge</b></li>
</menu>
<br />
<dl><table border="1" style="width: 100%px;"><tbody>
<tr><td width="50%"><div align="center">
<img border="0" height="205" src="http://www.woodbridge.tased.edu.au/mdc/Pumpkin%20Sponge.jpg" width="272" /></div>
<dl>
<dt><span style="font-size: x-small;"><i>Tethya </i>sp. ? - Pumpkin Sponge</span></dt>
<dt><span style="font-size: x-small;">Picture: MDC</span></dt>
</dl>
</td><td valign="top" width="50%">
<dl>
<dt><span style="font-size: x-small;"><b>Habitat</b>: Reef, sand, muddy bottom; 2 - 15 m depth</span></dt>
<dt><span style="font-size: x-small;"><b>Distribution</b>: Unknown due to lack of taxonomic resolution</span></dt>
<dt><span style="font-size: x-small;"><b>Maximum size:</b> Up to approximately 300 mm diameter</span></dt>
<dt><span style="font-size: x-small;"><b>Diet</b>: Plankton (filter feeder)</span></dt>
<dt><span style="font-size: x-small;"><b>Comments: </b></span></dt>
<dt><span style="font-size: x-small;">Staff at the Marine Discovery Centre find Pumpkin Sponges commonly in the D'Entrecasteaux Channel, often hauling them up with the dredge. Sponges often form what's called a "Sponge Garden" where large numbers of sponges can be found.</span></dt>
</dl>
</td></tr>
</tbody></table>
</dl>
<br />
<menu>
<li><b><i>Carteriospongia caliciformis </i>- Plate Sponge</b></li>
</menu>
<br />
<dl><table border="1" style="width: 100%px;"><tbody>
<tr><td width="50%"><div align="center">
<img border="0" height="204" src="http://www.woodbridge.tased.edu.au/mdc/Plate%20Sponge1.jpg" width="271" /></div>
<dl>
<dt><span style="font-size: x-small;"><i>Carteriospongia caliciformis - </i>Plate Sponge</span></dt>
<dt><span style="font-size: x-small;">Picture: MDC</span></dt>
</dl>
</td><td valign="top" width="50%">
<dl>
<dt><span style="font-size: x-small;"><b>Habitat</b>: Moderately exposed reef, 5 - 35 m depth</span></dt>
<dt><span style="font-size: x-small;"><b>Distribution</b>: SA to Victoria and around Tasmania</span></dt>
<dt><span style="font-size: x-small;"><b>Maximum size:</b> Up to approximately 300 mm diameter</span></dt>
<dt><span style="font-size: x-small;"><b>Diet</b>: Plankton (filter feeder)</span></dt>
<dt><span style="font-size: x-small;"><b>Comments: </b></span></dt>
<dt><span style="font-size: x-small;">This species lacks spicules and only has spongin for support. It occurs commonly on deeper reefs in areas of high current flow. The irregular green colour of the sponge may be caused by green symbiotic algae growing on the surface. </span></dt>
</dl>
</td></tr>
</tbody></table>
</dl>
<br />
<menu>
<li><span style="font-size: small;"><b><i>Dendrilla rosea </i>- Rosea Sponge</b></span></li>
</menu>
<br />
<dl><table border="1" style="width: 100%px;"><tbody>
<tr><td width="50%"><div align="center">
<img border="0" height="207" src="http://www.woodbridge.tased.edu.au/mdc/Rosea%20Sponge1.jpg" width="271" /></div>
<dl>
<dt><span style="font-size: x-small;"><i>Dendrilla rosea</i> - Rosea Sponge</span></dt>
<dt><span style="font-size: x-small;">Picture: MDC</span></dt>
</dl>
</td><td valign="top" width="50%">
<dl>
<dt><span style="font-size: x-small;"><b>Habitat</b>: Moderately exposed reef, 3 - 22 m depth</span></dt>
<dt><span style="font-size: x-small;"><b>Distribution</b>: SA to NSW and around Tasmania</span></dt>
<dt><span style="font-size: x-small;"><b>Maximum Size:</b> Length to 400 mm</span></dt>
<dt><span style="font-size: x-small;"><b>Diet</b>: Plankton (filter feeder)</span></dt>
<dt><b><span style="font-size: x-small;">Comments</span></b><span style="font-size: x-small;">: </span></dt>
<dt><span style="font-size: x-small;">Bright pink sponge with deeply ruffled surface. Can be erect or encrusting.</span></dt>
</dl>
</td></tr>
</tbody></table>
</dl>
<br />
<menu>
<li><b><i>Siphonochalina </i>sp. ? - Finger Sponge</b></li>
</menu>
<br />
<dl><table border="1" style="width: 100%px;"><tbody>
<tr><td width="50%"><div align="center">
<img border="0" height="203" src="http://www.woodbridge.tased.edu.au/mdc/Finger%20Sponge1.jpg" width="270" /></div>
<dl>
<dt><span style="font-size: x-small;"><i>Siphonochalina </i>sp. ? - Finger Sponge</span></dt>
<dt><span style="font-size: x-small;">Picture: MDC</span></dt>
</dl>
</td><td valign="top" width="50%">
<dl>
<dt><span style="font-size: x-small;"><b>Habitat</b>: Exposed reef, 20 - 35 m depth</span></dt>
<dt><span style="font-size: x-small;"><b>Distribution</b>: Eastern Tasmania</span></dt>
<dt><span style="font-size: x-small;"><b>Maximum size:</b> Length to 150 mm</span></dt>
<dt><span style="font-size: x-small;"><b>Diet</b>: Plankton (filter feeder)</span></dt>
<dt><span style="font-size: x-small;"><b>Comments: </b></span></dt>
<dt><span style="font-size: x-small;">This species has long tubular extensions (fingers!). Common on deep Tasmanian reefs.</span></dt>
</dl>
</td></tr>
</tbody></table>
<dt> </dt>
</dl>
<br />Anonymoushttp://www.blogger.com/profile/15125980005528241488noreply@blogger.com0