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NUCULANIDAE |
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Poroleda ensicula (Angas, 1877) Description: Shape equivalve, inequlateral, very elongate so as to appear scythe-like. Anterior end rounded, posterior end drawn out into long rostrum; posterior dorsal margin concave. Umbo at anterior quarter, small. Hinge taxodont, with about 11, V-shaped teeth on anterior side and 21 similarly shaped teeth on posterior side. Interior smooth apart from a central dividing ridge near end of rostrum. Exterior with very fine, regular concentric ridges with faint radial ridges (that are strongest anteriorly), and coarse growth lines dorsally. Shell translucent white with thin greenish periostracum. Size: Up to 17 mm in length. Distribution: Port Stephens, NSW, southwards to south-eastern Tasmania. Uncommon. Habitat: Known from 40-149 m depth. Comparison: This species is about the same length as Poroleda spathula, but tapers more rapidly posteriorly. Both the anterior and posterior hinge teeth are V-shaped, while in P. spathula the anterior teeth are V-shaped but the posterior ones are flat plates. This species occurs in shallower water (down to 149 m) than P. spathula, which occurs down to 550 m. Fig. 1: 5 miles (8 km) east of Sydney Heads (C.033687)
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