Mactridae,

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrast ...

the trough shells or duck clams, is a

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

of saltwater clams,

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military ...

bivalve Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class (biology), class of marine and freshwater Mollusca, molluscs that have laterally compressed bodies enclosed by a shell consisting of two hing ...

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

s in the

order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of ...

Venerida Venerida (formerly Veneroida) is an order of mostly saltwater but also some freshwater bivalve molluscs. This order includes many familiar groups such as many clams that are valued for food and a number of freshwater bivalves. Since the 2000s, t ...

Description

These clams have two short siphons, each with a horny sheath. The shell is shaped like a rounded-cornered equilateral triangle and there is a slight gape at the posterior. Each valve bears two cardinal teeth with four lateral teeth on the right valve and two on the left. The foot is white and wedge-shaped. They mostly inhabit the

neritic zone The neritic zone (or sublittoral zone) is the relatively shallow part of the ocean above the drop-off of the continental shelf, approximately in depth. From the point of view of marine biology it forms a relatively stable and well-illuminated ...

Ecology

Trough shells burrow in sand or fine gravel and never in muddy substrates.

Genera

According to the World Register of Marine Species (2012), this family contains 37 genera: * '' Anatina'' Schumacher, 1817 * '' Austromactra'' Iredale, 1930 * '' Barymactra'' Cossmann in Cossmann & Peyrot, 1909 * '' Coelomactra'' Dall, 1895 * ''

Crassula ''Crassula'' is a genus of succulent plants containing about 200 accepted species, including the popular jade plant (''Crassula ovata''). They are members of the stonecrop family (Crassulaceae) and are native to many parts of the globe, but cu ...

'' Marwick, 1948 * '' Cyclomactra'' Dall, 1895 * '' Darina'' Gray, 1853 * '' Diaphoromactra'' Iredale, 1930 * '' Eastonia'' Gray, 1853 * '' Harvella'' Gray, 1853 * '' Heterocardia'' Deshayes, 1855 * '' Huberimactra'' Cosel & Gofas, 2018 * '' Leptospisula'' Dall, 1895 * '' Lutraria''

Lamarck Jean-Baptiste Pierre Antoine de Monet, chevalier de Lamarck (1 August 1744 – 18 December 1829), often known simply as Lamarck (; ), was a French naturalist, biologist, academic, and soldier. He was an early proponent of the idea that biolo ...

, 1799 * '' Mactra''

Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...

, 1767 * '' Mactrellona'' Marks, 1915 * '' Mactrinula'' Gray, 1853 * '' Mactromeris'' Conrad, 1868 * '' Mactrotoma'' Dall, 1894 * '' Maorimactra'' Finlay, 1928 * '' Meropesta'' Iredale, 1929 * '' Mulinia'' Gray, 1837 * '' Oxyperas'' Mörch, 1853 *'' Pseudocardium'' Gabb, 1866 * '' Raeta'' Gray, 1853 * '' Rangia'' Desmoulins, 1832 * '' Resania'' Gray, 1853 * '' Scalpomactra'' Finlay n Marwick 1928 * ''

Scissodesma ''Scissodesma'' is a genus of bivalves Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consis ...

'' Gray, 1837 * '' Simomactra'' Dall, 1894 * '' Spisula'' Gray, 1837 * '' Standella'' Gray, 1853 * '' Tanysiphon'' Benson, 1858 * '' Tresus'' Gray, 1853 * ''

Trinitasia ''Trinitasia'' is a genus of saltwater clams, marine bivalve mollusks in the family Mactridae Mactridae, common name the trough shells or duck clams, is a family of saltwater clams, marine bivalve mollusks in the order Venerida. Descripti ...

'' Maury, 1928 * '' Tumbeziconcha'' Pilsbry & Olsson, 1935 * '' Zenatia'' Gray, 1853 * '' Zenatina'' Gill & Darragh, 1963

References

* Powell A. W. B., ''New Zealand Mollusca'', William Collins Publishers Ltd, Auckland, New Zealand 1979 Bivalve families Taxa named by Jean-Baptiste Lamarck Extant Cretaceous first appearances {{Bivalve-stub