Temporal range: Cretaceous to Present
Shell of Spisula solida
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Bivalvia
Order: Veneroida
Family: Mactridae
Lamarck, 1809

See text.

Mactridae, also known as trough shells or duck clams, is a family of marine bivalve clams of the order Veneroida.


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


  • Anatina Schumacher, 1817
  • Lutraria Lamarck, 1799
  • Longimactra Finlay, 1928
  • Mactra Linnaeus, 1767
  • Mactrellona
  • Mactromeris Conrad, 1868
  • Mactrotoma Dall, 1894
  • Mulinia Gray, 1837
  • Raeta Gray, 1853
  • Rangia Desmoulins, 1832
  • Resania Gray, 1852
  • Scalpomactra Finlay, 1928
  • Simomactra Dall, 1894
  • Spisula Gray, 1837
  • Tresus Gray, 1853
  • Zenatia Gray, 1853


  1. ^ Barrett, J. H. and C. M. Yonge, 1958. Collins Pocket Guide to the Sea Shore. P. 156. Collins, London