PTERINEIDAE, MILLER, 1877

BOYD, DONALD W. & NEWELL, NORMAN D., 2001, Silicified Leptodesma (Bivalvia; Pteriomorphia) from the Texas Permian, American Museum Novitates 3347, pp. 1-11 : 2-3

THE FAMILY PTERINEIDAE

For students of Paleozoic bivalves, the pteriomorphian family Pterineidae poses more than its share of problems. It is composed of numerous Paleozoic genera with or without surface ornament. They are characterized by retrocrescent shape, forward­positioned beak, small anterior auricle, large posterior wing, and a dentate hinge plate with a duplivincular ligament insertion (Newell and LaRocque, 1969: 299). The poor preservation typical of pterineid fossils has resulted in a proliferation of poorly characterized taxa with little morphological information other than general shape and ornamentation.

The unsatisfactory status of pterineid generic­level taxonomy was recognized decades ago by McAlester (1962: 12, 26) who eloquently expressed his frustration in assigning generic names to Devonian pterioid species. The uncertainty concerning taxonomic significance of particular morphological features has been echoed by others (e.g., Pojeta et al., 1986: 92). Given this state of affairs, it is not surprising that phylogenetic relationships of the Pterineidae are matters for speculation. In a recent paper dealing with bivalve phylogeny, Waller (1998: 26) interpreted the Pterineidae as a paraphyletic stem group that gave rise to several other pteriomorphian clades. In his analysis, pterineid plesiomorphic characters include the duplivincular ligament and the shell structure consisting of inner nacreous layers and outer prismatic calcitic layers.

Another controversial subject involves pterineid mode of life. Theories and evidence concerning life habits were reviewed by Johnston (1993). That paper, based on unusually well­preserved Devonian material, provides a perceptive analysis of the possible functional significance of various morphologic features of pterineid shells.

The classification below follows that of the Treatise on Invertebrate Paleontology (Newell, 1969).