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MARGARITIDAE |
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Pinctada nigra (A. Gould, 1850) Description: Shape Shell with left valve more inflated than right; umbo near anterior end of dorsal margin; dorsal margin straight, anterior margin with deep byssal notch in right valve, posterior margin convex to concave, ventral margin rounded. Hinge line straight, ligament in a broad triangular pit behind umbo. Interior nacreous, with a wide non-nacreous dark margin; single oval-shaped muscle scar. Exterior smooth initially, becoming irregularly foliaceous, finger-like processes developing towards margins of mature shells. Shell black or purple-black. Size: In Australia, up to 52 m in length. Distribution: Indo-West Pacific. In Australia, reported distribution is from a few records from Cape Leveque, north-west Australia, and then from Cape York southwards to Sydney, NSW. Habitat: Lower intertidal and shallow subtidal, attached by byssus to solid substrates. Remarks: Genetic analysis by Tėmkin (2010) grouped this species closely with P. albina; he suggested that the two were colour morphs or a single species, but there are differences in shell shape that make this unlikely. Fig. 1: Heron Island, Capricorn Group, Qld (C.168099) |
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