How many different species of mollusks are alive today?

How many different species of mollusks are alive today?

There are approximately 160,000 living species and probably 70,000 extinct species of mollusks. They are typically divided into ten classes, of which two are extinct. The major classes of living mollusks include gastropods, bivalves, and cephalopods (Figure below).

What are the 6 molluscs?

Class Gastropoda – snails, slugs, limpets, whelks, conchs, periwinkles, etc. Class Bivalvia – clams, oysters, mussels, scallops, cockles, shipworms, etc. The Class Scaphopoda contains about 400 species of molluscs called tooth or tusk shells, all of which are marine.

What are the 8 classes of Mollusca?

The Phylum Mollusca consist of 8 classes: 1) the Monoplacophora discovered in 1977; 2) the worm-like Aplacophora or solenogasters of the deep sea; 3) the also worm-like Caudofoveata; 4) the Polyplacophora, or chitons; 5) the Pelecypoda or bivalves; 6) the Gastropoda or snails; 7) the Scaphopoda, or tusk shells; and 8) …

What are the 4 main classes of mollusks?

Mollusks can be segregated into seven classes: Aplacophora, Monoplacophora, Polyplacophora, Bivalvia, Gastropoda, Cephalopoda, and Scaphopoda. These classes are distinguished by, among other criteria, the presence and types of shells they possess.

What are the 3 main mollusks?

The three major groups of mollusks are gastropods, bivalves, and cephalopods (SEF ul o pods). The largest group is the gastropods. These are mollusks like snails and slugs that have just one shell or no shell at all. Gastropods creep along on their broad foot.

What 2 other parts do all mollusks have?

All mollusks have a visceral mass, a mantle, and a foot. The visceral mass contains the digestive, excretory, and reproductive organs. The mantle is a covering.

What are the types of molluscs?

Classification

Class Major organisms
Gastropoda all snails and slugs including abalone, limpets, conch, nudibranchs, sea hares, sea butterflies
Bivalvia clams, oysters, scallops, geoducks, mussels, rudists†
Polyplacophora chitons
Cephalopoda squid, octopuses, cuttlefish, nautiluses, Spirula, belemnites†, ammonites†

What are the 3 classes of phylum Mollusca?

Summary

  • Mollusks are subdivided into seven classes with most species found in three of those classes: Gastropoda, Bivalvia, and Cephalopoda.
  • Gastropods make up the largest class of mollusks, and they include both snails and slugs.

What are the 3 class of mollusk What do they all share how are they each different?

The three main parts of a mollusk’s body include a muscular foot, a visceral mass, and a mantle. The three main types of mollusks are gastropods, bivalves, and cephalopods. Gastropods, like slugs and snails, can live on land or in the water.

What are the 3 classes of mollusk What do they all share how are they each different?

What are the 3 distinct body parts of a mollusk?

Despite their diversity, mollusks share in common a three-part body plan that includes a head, a foot and a visceral mass.

How many body parts do molluscs have?

In general, mollusks have 3 body regions: a head, a visceral mass, and a “foot.” The head contains the sense organs and “brain,” while the visceral mass contains the internal organs. The “foot” is the muscular lower part of the body which is in contact with the substrate.