Mollusca

=Phylum Mollusca (means "soft")= Molluscs show an amazing degree of diversity, yet all have certain features in common. All have soft bodies and have a strong muscular foot, which is used for movement or grasping. They also have gills, a mouth and an anus. A feature unique to molluscs is a file-like, rasping tool called a radula. This structure allows them to scrape algae and other food off rocks and even to drill through the shell of prey or catch fish. The diversity of molluscs impressively demonstrates how a basic body plan can evolve into a variety of different forms adapted to specific environments. For example, the hard shell in a land-dwelling snail is relatively large and serves to protect the animal. In the fast-swimming squid, however, the shell is reduced to a small internal pen-shaped structure.

Most molluscs are bilaterally symmetrical and have well-defined circulatory, respiratory, excretory, and digestive systems. The organisms in the phylum Mollusca are characterized by having three main body areas: a head-foot (sensory and locomotion structures), a visceral mass (excretory, digestive, and circulatory structures), and a mantle (which secretes the shell). The gills, which function in respiration, are located between the visceral mass and the mantle.

Reproduction is sexual and may be simple or highly complex. The fertilized egg develops into a swimming form called a trochophore larva, this then elongates to become a veliger larva, characteristic of mollusks, and differing in form in the different classes.

**Polyplacophora** - the chitons **Gastropoda** - snails, slugs **Bivalvia** - clams, oysters, etc. **Cephalopoda** - squid, octopus, etc.
 * Classes of Mollusca: **

**Student Zoo Keeper Pages of Species: (Enter Your Species Pages Below)**
Southern Pygmy Squid (Zookeeper: Sidney Baker) The Lesser (Southern) Blue Ring Octopus (Zookeeper: Taylor Cebuly) Gulf Oysters (Zookeeper: Kenzie Davidson) Caribbean Armstripe Octopus (Zookeeper: Shaiann Etwara) Common Atlantic Octopus (Zookeeper: Erin Holbert) Quahog Clam (Zookeeper: Syed Islam) Kumamoto Oyster (Zookeeper: Marissa Jenkins) Japanese Flying Squid (Zookeeper: Hannah Jones) The Greater Blue-Ringed Octopus (Zookeeper: James K. Kanthachack) Humboldt Squid (Zookeeper: Savannah Kelley) Bithynia tentaculata (Zookeeper: Tori Lopez) Vampire Squid (Zookeeper Whopper) Atlantic longarm octopus (Zookeeper: Heath McGregor) Brownstripe Octopus (Zookeeper: Ramon Prieto) Apple Snail (Zookeeper: Lindsey Rafus) Leafy Hornmouth ( Zookeeper: Sarah Reimer) Mimic Octopus (Zookeeper: Paco Rodriguez) Caribbean Reef Octopus (Zookeeper: Paige Ryder) Striped Pajama Squid (Zookeeper: Haley Shelton) __Fuzzy Chiton__ (Zookeeper: Jeffrey Slape) Colossal Squid (Zookeeper: Riley Stewart) Sea Slug- Flabellina Funeka (Zookeeper: Jessica Tolliver) Hawaiian Bobtail Squid (Zookeeper Rachel Tolliver) Giant African Snail (Zookeeper: Ashley Veilleux) Sea Angel (Zookeeper: Hannah Williams) Giant Squid(Zookeeper: Jayme Willingham) __Lined Chiton__ (Zookeeper: Jesse Wilson) Pacific Oyster (Zookeeper: Katie Woolen) Veined (Coconut) Octopus (Zookeeper: Elisabeth Young)

http://www.pbs.org/kcet/shapeoflife/animals/molluscs.html //McGraw-Hill Encyclopedia of Science and Technology//, 5th edition, published by The McGraw-Hill Companies, Inc. corbis.com
 * Information and Photo References:**