Article: New tube-bearing antillocaprinid rudist bivalves from the Maastrichtian of Jamaica

Two genera of tube-bearing antillocaprinid rudist bivalves from the Maastrichtian of Jamaica are recognised: Titanosarcolites Trechmann and Parasarcolites gen. nov. Titanosarcolites is recumbent, broadly equivalve and coils parallel to the myocardinal line, with tubes on the anteriodorsal, anterior, and anterioventral regions of the inner layer; there are two teeth and two teeth-like myophores in the left valve. Sockets for teeth have conical tabulae, those for myophores are filled with normal shell structure. A ligamental cavity is lacking. Parasarcolites is recumbent, with equal, subequal or moderately inequal valves, and the plane of coiling is at an angle of 34-63 degrees to the mediocardinal line. It has tubes in the dorsal and anterior-dorsal regions, and a myocardinal structure with blade like myophores, with the posterior tooth and socket strongly flattened. The position of the ligament is indicated by a comma-shaped cavity situated dorsalwards of the posterior tooth. Additional toothlets are present in the left valve. All sockets are filled with canal-bearing shell-structure. Five new species of Parasarcolites are described from the Upper Maastrichtian of Jamaica: Parasarcolites atkinsoni, P. baileyi, P. greeni, P. monotubularis and P. quadratus.