Limatula species belong to the bivalve mollusk family Limidae (the file shells). The genus Limatula includes bivalves with shells that are small, white or glassy, usually fragile, somewhat elongated and oblique, inflated, often with axial ornamentation, and with prominent beaks. Small auricles are usually present, an internal median groove may be present, and the hinge is without teeth (in contrast to the very similar Limea, which have a series of short teeth on either side of the resilifer [a structure on each shell valve supporting the internal ligament or resilium]). Limatula (and Limea) are generally well under 1 cm in size and are found in ocean sediments throughout the world. (Allen 2004; Oliveira and Absalão 2008)
Allen (2004) reviewed the Recent Limatula species from the Atlantic and provided technical diagnoses for the family Limidae, the genus Limatula (as well as Limea), and the nine Limatula species known from the Atlantic (six of which he describes for the first time). Fleming (1978) reviewed the living and fossil Limatula species from the southwest Pacific and discussed the challenges of recognizing species boundaries based on shell morphology. Oliveira and Absalão (2008) revised the deep water Limidae of Brazil, recording five species of Limatula and one Limea.
Limatula attenuata Dall, 1916, Limatula confusa (E. A. Smith, 1885), Limatula gwyni (Sykes, 1903), Limatula hendersoni Olsson and McGinty, 1958, Limatula hyalina A. E. Verrill and Bush, 1898, Limatula hyperborea A. S. Jensen, 1909, Limatula japonica A. Adams, 1864, Limatula regularis A. E. Verrill and Bush, 1898, Limatula saturna Bernard, 1978, Limatula setifera Dall, 1886, Limatula similaris (Dall, 1908), Limatula subauriculata (Montagu, 1808), Limatula subovata (Jeffreys, 1876), Limatula sulcata (Brown, 1827), Limatula vancouverensis Bernard, 1978