Geological age:
Recent.
Description:
"T. rudis, crassa, inequivalvis, concentricè lamellata, cinerea, obliqua, trapezoidea; latere byssali dilatato, semicirculari; sinu byssali profundo; apice adunco; latere postico rectilineari, obliquo, producto; margine cardinali obliquo: area cardinalis triangularis, sulcis obliquis ad sex arata: margarita ex argenteo-purpurasens; limbo lato, retrò. Long. 2½; alt. 1¾; lat. ⅜ poll. Hab. Sandwich Islands.
The obliquity of this species and the small number of its cardinal sulci are among its most prominent characters." [Gould, 1850: 311.]
Type locality:
"Hab. Sandwich Islands" [Gould, 1850: 311].