Mactridae

Mactridae Temporal range: Cretaceous to Present
Shell of Spisula solida
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Bivalvia
Order:	Venerida
Superfamily:	Mactroidea
Family:	Mactridae Lamarck, 1809
Genera
See text.

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

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. ^[1]

Ecology

Trough shells burrow in sand or fine gravel and never in muddy substrates. ^[1]

Subfamilies and genera

Mactra stultorum

Lutraria lutraria

According to the World Register of Marine Species (2025), this family contains 56 genera and is split into the following subfamilies: ^[2]

Subfamily Darininae

• † Darcinia Clark, 1946
• Darina J. E. Gray, 1853

Subfamily Lutrariinae

• Eastonia J. E. Gray, 1853
• Heterocardia Deshayes, 1855
• Lutraria Lamarck, 1799
• Meropesta Iredale, 1929
• Standella J. E. Gray, 1853
• Tresus J. E. Gray, 1853 ^[3]
• Zenatia J. E. Gray, 1853
• Zenatina Gill & Darragh, 1963

Subfamily Mactrinae

• † Allomactra Tomlin, 1931
• Austromactra Iredale, 1930
• Barymactra Cossmann, 1909
• Coelomactra Dall, 1895
• Crassula Marwick, 1948
• Cyclomactra Dall, 1895 ^[4]
• Diaphoromactra Iredale, 1930
• Harvella J. E. Gray, 1853
• Huberimactra Cosel & Gofas, 2018
• Leptospisula Dall, 1895
• Mactra Linnaeus, 1767 ^[3]
• Mactrella J. E. Gray, 1853
• Mactrellona J. G. Marks, 1951
• Mactrinula J. E. Gray, 1853 ^[5]
• Mactromeris Conrad, 1868
• Mactrotoma Dall, 1894 ^[3]
• Maorimactra H. J. Finlay, 1928
• Mulinia J. E. Gray, 1837 ^[3]
• Oxyperas Mörch, 1853
• † Pseudocardium Gabb, 1866
• Rangia Desmoulins, 1832 ^[3]
• † Sarmatimactra Korobkov, 1954
• Scalpomactra H. J. Finlay, 1928
• Scissodesma Gray, 1837
• Simomactra Dall, 1894 ^[3]
• Spisula J. E. Gray, 1837 ^[3]
• Trinitasia Maury, 1928
• Tumbeziconcha Pilsbry & Olsson, 1935
• Mactrona Marwick, 1952
• Petromactra Saul, 1973

Subfamily Resaniinae

• Resania J. E. Gray, 1853

Subfamily Tanysiphoninae

• Tanysiphon W. H. Benson, 1858

Incertae sedis

• † Aktschagylia Starobogatov, 1970
• † Aliomactra Stephenson, 1952
• † Andrussella Korobkov, 1954
• † Avimactra Andrusov, 1905
• † Caspimactra A. A. Ali-Zade & Kabakova, 1969
• † Chersonimactra Paramonova, 1978
• † Cryptomactra Andrussow, 1902
• † Cymbophora Gabb, 1869
• † Eopapyrina Woodring, 1982
• † Geltena Stephenson, 1946
• † Ionesimactra Signorelli, 2023
• † Kirghizella Andrusov, 1902
• † Mactrodesma Conrad, 1869
• Mactrona Marwick, 1952
• † Mulinoides Olsson, 1944
• † Nelltia Stephenson, 1952
• † Nymphactra Stilwell & Zinsmeister, 1992
• † Ovamactra Woodring, 1982
• Petromactra Saul, 1973
• † Planimactra Ionesi, 1986
• † Podolimactra Ionesi, 1986
• † Praerangia Cossmann, 1908
• † Priscomactra Stephenson, 1952
• † Pseudomactra Steklov, 1960
• † Pteroluter Saul, 1973
• † Stereomactra Stewart, 1930
• † Stiphromactra Böhm, 1929
• † Tenuimactra Garvie, 1996
• † Willimactra Saul, 1973
• † Zenatiopsis Tate, 1880

References

1. Barrett, J. H.; Yonge, C. M. (1958). Collins Pocket Guide to the Sea Shore. London (UK): Collins. p. 156.
2. Gofas, Serge (2017-11-14). "Mactride Lamarck, 1809". WoRMS. World Register of Marine Species . Retrieved 2025-03-08.
3. Scott, Paul V. "Mactridae". Integrated Taxonomic Information System.
4. Kong, Lingfeng; Li, Qi; Qiu, Zhaoxing (2007). "Genetic and morphological differentiation in the clam Coelomactra antiquata (Bivalvia: Veneroida) along the coast of China". Journal of Experimental Marine Biology and Ecology. 343: 110–117. doi:10.1016/j.jembe.2006.12.003.
5. Coan, E. V.; Valentich-Scott, P. (2012). Bivalve seashells of tropical West America. Marine bivalve mollusks from Baja California to northern Peru. pp. 2 vols, 1258 pp.

• Powell A. W. B., New Zealand Mollusca, William Collins Publishers Ltd, Auckland, New Zealand 1979 ISBN   0-00-216906-1