Pecten consobrinus Tate, 1886
TATE, R. 1886. The lamellibranchs of Older Tertiary of Australia (part 1). Transactions and Proceedings and Report of the Royal Society of South Australia, 8: 96-158. [p. 104, pl. 3, fig. 6]
«Pecten consobrinus, spec. nov. Plate iii., fig. 6.
Shell orbicular, fan-shaped, slightly convex, equilateral, subinequivalve, the left valve somewhat flatter. Ornamented with about eight radial folds and numerous (about 100) thickish riblets; the riblets are rigid, unequal in size, and separated by irregular intervals which are minutely granular and usually broader than the riblets.
Right valve with rayed, unequal ears; anterior ear larger, subaliiform, slightly notched on the underside; posterior ear triangular, perpendicularly truncated. Ears of left valve unequal, radially ribbed; the anterior one larger, triangular, outer margin curved ; posterior ear triangular, perpendicularly truncated. Dimensions.— Length and height about 85 millimetres. Localities.— Oyster banks of the Upper Aldinga series at Aldinga and Hallett's Cove, St. Vincent Grulf. It is with some hesitation that I separate these shells from P. bifrons, but the slight differential characters relied on are observable at all stages of growth; thus left valves of 15 millimetres diameter are distinguished by their three-ridged radial ribs; at 30 millimetres diameter, whilst P. bifrons has yet the elevated simple scaly ribs and plain furrows, P. consobrinus has almost lost the plicae which are replaced by four or five threads, and about three occupy the furrows; these divergencies culminate in the very numerous radial threads and obsolete folds of the adult. Similar changes are observable in the other valve. P. consobrinus is moreover less inequivalve than P. bifrons.» RALPH TATE, 1886
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R. Tate, 1886, plate 3.
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