Shell thick, inequivalve, inequilateral. Hinge: upper valve with a thick oblique tooth fitting into a cavity of the lower valve; ligament external. Two adductor muscle scars, of different sizes (dimyarism); pallial line without sinus.
 

« Shell irregular, very inequivalve, with cupped left or right valve attached to substratum and opposite valve flattened; umbones recurved, prosogyrate, unequal; attached valve frequently with deep subumbonal chamber; sculpture frequently with foliaceous commarginal frills; top valve commarginal lamellae or spines, frequently eroded; adult hinge plate strong with ponderous teeth » – Valentich-Scott & Coan: “A new species of Chama (Bivalvia, Chamidae) from Mexico”, Zootaxa 2446, Auckland 2010, p.65.
 

Cemented to substratum like the genus Chama; umbones opisthogyrate. « …To this species I refer Chama pulchella Reeve (Conch. Icon. 4, 1840, fig. 10a), a species in which Reeve comprised not only dextral but also sinistral shells. He figures in fig. 10b a specimen with the umbones turned from right to left, which, in its exterior appearance (colour and sculpture) is strikingly similar to the dextral fig. 10a. Nevertheless, the specimen 10 6 must be distinguished from that of fig. 10a and referred not only to a distinct species but also to a new genus, Pseudochama, comprising the sinistral Chamas and characterized by differences in dentition and anatomy… » – N. H. Odhner: “Results of Dr. E. Mjöbergs Swedish scientific expeditions to Australia 1910-1912. Mollusca”, Kungliga Svenska Vetenskapsacademiens Handlingar vol.52(16), Stockholm 1917, p.28.