Striatoamussium Aberhan, 1998
ABERHAN, M. 1998. Early Jurassic Bivalvia of western Canada. Part I. Subclasses Palaeotaxodonta, Pteriomorphia and Isofilibranchia. Beringeria, 21: 57-150, text-figs. 1-14, pls. 1-19. [p. 100]
«Subgenus Striatoamussium subgen. nov.
Type species. Propeamussium (Striatoamussium) patriciae POULTON 1991.
Derivation of name. From striatus (lat.) = striated, and amusium (gr.) = raw.
Diagnosis. Propeamussiid bivalve with exterior of both valves ornamented with radial riblets; byssal notch moderately deep; interior of both valves with radial costae.
Remarks. Apart from internal radial costae, the presence of a radial ornament on the exterior of both valves is regarded as the main diagnostic feature of the new subgenus. The latter feature serves to distinguish Striatoamussium from the closely related Parva- mussium, in which only the left valve is commonly covered with radial striae or riblets, and from Propea- mussium s.s., in which an external ornament is absent on both valves. In addition, the new subgenus apparently attains a considerably larger adult size and a thicker shell than typical representatives of Jurassic P. (Parvamussium).»
MARTIN ABERHAN, 1998
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Propeamussium (Striatoamussium) patriciae Poulton 1991; M. Aberhan, 1998, Early Jurassic Bivalvia of western Canada. Part I. Subclasses Palaeotaxodonta, Pteriomorphia and Isofilibranchia, plate 11, figures 1, 3, 5, 7.
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