|Atlantic molluscan assemblage dominated by two species of Crassinella (Bivalvia: Crassatellidae)|
Lyons, W.G. (1989). Atlantic molluscan assemblage dominated by two species of Crassinella (Bivalvia: Crassatellidae). Am. Malacol. Bull. 7(1): 57-64
In: American Malacological Bulletin. American Malacological Union: Hattiesburg. ISSN 0740-2783; e-ISSN 2162-2698
Composition > Community composition
Environments > Aquatic environment > Benthic environment
Sediments > Clastics > Sand
Crassinella lunulata (Conrad, 1834) [WoRMS]; Mollusca [WoRMS]
Molluscan species (135) were obtained in benthic grab samples during 12 bimonthly periods (Sept 1971-July 1973) at five station (depths 7-11 m) near Hutchinson Island, east Central Florida; 33 characteristic species constituted 90% of the 4135 specimens. Species distributions were influenced strongly by sediment composition. Compacted fine and very fine sands of the beach terrace supported few mollusks. Well-sorted medium sands supported a small but abundant species group at an offshore shoal, and two larger species groups were associated with coarse sands and with large shell particles that entrapped mud and silt in a trough between the shoal and terrace. Two bivalve species were numerically dominant. Crassinella lunulata contributed 33% of all specimens and occurred among large shell particles in the trough; C. dupliniana contributed 14% of all specimens and favored medium sands at the shoal. C. dupliniana, originally described as a fossil, has not been recorded previously among living fauna.