Search results
Results from the WOW.Com Content Network
Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks [a] (/ ˈ m ɒ l ə s k s /). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda . [ 5 ]
List of mollusc orders illustrates the 97 orders in the phylum Mollusca, the largest marine animal phylum. 85,000 extant species are described, [1] making up 23% of described marine organisms. [ 2 ] Class Aplacophora
Malacology [a] is the branch of invertebrate zoology that deals with the study of the Mollusca (molluscs or mollusks), the second-largest phylum of animals in terms of described species [1] after the arthropods. Mollusks include snails and slugs, clams, and cephalopods, along with numerous other kinds, many of which have shells.
Aplacophora / æ p l ə ˈ k ɒ f ər ə / is a possibly paraphyletic taxon. This is a class of small, deep-water, exclusively benthic, marine molluscs found in all oceans of the world. [1]
The class Gastropoda is a diverse and highly successful class of mollusks within the phylum Mollusca. It contains a vast total of named species, second only to the insects in overall number. The fossil history of this class goes back to the Late Cambrian.
In some mollusks the mantle cavity is a brood chamber, and in cephalopods and some bivalves such as scallops, it is a locomotory organ. The mantle is highly muscular. In cephalopods the contraction of the mantle is used to force water through a tubular siphon, the hyponome , and this propels the animal very rapidly through the water.
The mollusc (or mollusk [spelling 1]) shell is typically a calcareous exoskeleton which encloses, supports and protects the soft parts of an animal in the phylum Mollusca, which includes snails, clams, tusk shells, and several other classes. Not all shelled molluscs live in the sea; many live on the land and in freshwater.
Males (n = 870) had a mean shell diameter of 131.9±2.6 mm, compared to 118.9±7.5 mm in females (n = 86). The Osprey Reef N. pompilius population is the second smallest known in terms of mean shell diameter, after the dwarf form from the Sulu Sea (130.7 mm and 115.6 mm, respectively).