Pseudohinnites Dijkstra, 1989
DIJKSTRA, H. H. 1989. Pseudohinnites levii gen. et spec.nov. (Mollusca, Bivalvia: Pectinidae) from New Caledonia. Basteria, 53 (1-3): 29-33, figs. 1-3. [p. 29]
«Pseudohinnites gen. nov.
Diagnosis. — Shell medium-sized, fragile, inequivalve and very irregular, with a Hinnites-like appearance. Auricles inequal, in the left valve not very much contrasted against the valve; anterior auricle slightly longer than posterior, hinge line straight.
Left valve convex, right valve flat, both valves very irregular, with marked growth lines. Exterior of left valve with irregular radial costae and concentric lamellae overlying the radial costae and interstices. Right valve smooth, with irregular concentric waves or irregular depressions, giving a deformed appearance. Sculpture of left valve continued on the auricles, with radial costae and fine concentric lamellae. Auricles of right valve with a few radial costae near the hinge line only. An inactive and active ctenolium with three to five teeth are present. Type species. — Pseudohinnites levii spec, nov
Derivatio nominis. -- The new genus recalls in its general form and appearance a species of Hinnites.
Remarks. — Pseudohinnites resembles at first glance the genera Hinnites Defrance, 1821 [see description of the type species Hinnites cortesii Defrance, 1821 ( = Ostrea crispa Brocchi, 1814) from the North Italian Pliocene], and Crassadoma Bernard, 1986 (see description of the type species Lima gigantea Gray, 1825, in Bernard, 1986: 70-74).
The new genus differs from both Hinnites and Crassadoma by being quite fragile, whereas Hinnites and Crassadoma are solid and much larger. The juvenile stage of these is typical for “Chlamys”, whereas in Pseudohinnites the juveniles have the same conchological features as the adults. It has not been established that the deformed mature shell of Pseudohinnites is the result of idiomorphic growth caused by the substrate, as is the case in Hinnites and Crassadoma. Species of these two genera generally live on the continental shelf, from shallow water down to about 200 m, whereas Pseudohinnites is known only from the bathyal zone. Pseudohinnites in some aspects also resembles Hyalopecten Verrill, 1897. Species of this genus are also fragile, with an undulating external sculpture. Sometimes Pseudohinnites bears a slight resemblance to Hyalopecten with its irregular undulating sculpture of both valves. Hyalopecten also lives in the bathyal zone, but deeper down.» HENK H. DIJKSTRA, 1989
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Pseudohinnites levii spec. nov.; H. H. Dijkstra, 1989, Pseudohinnites levii gen. et spec.nov. (Mollusca, Bivalvia: Pectinidae) from New Caledonia, figures 1, 2.
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