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ARCHITECTONICIDAE |
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Psilaxis oxytropis (A. Adams, 1855) Description: Shell variable in height, spire convex in outline. Teleoconch whorls convex, smooth or with about 6 weak spiral threads and one or two stronger cords at bottom, forming moderate keel on periphery of last whorl. Base with obsolete spiral threads, with weak radial folds radiating from umbilicus; umbilicus open, 25–30% of base width, margin coarsely or more finely toothed, surrounded by a crenulate cord. Colour variable; background tan or fawn; sometimes alternating brown and white band at top of whorls; peripheral ribs alternating white and tan, with white patches sometimes expanding into radial streaks partway across whorls; base tan, umbilical margin white. Size: Up to 18.5 mm in diameter, commonly about 12 mm. Distribution: Indo-West Pacific. In Australia, from south-western WA northwards and around northern Australia, and then southwards to southern NSW. Habitat: Known from beach washup and down to 183 m. Apparently lives subtidally, as not encountered alive intertidally, Dredged as a fossil from Sydney Harbour. Moderately common. Comparison: See P. radiatus. Synonymy: Philippia manifesta Iredale, 1931 is a previously recognised synonym. Remarks: The biology and distribution of this species was described by Robertson (1970). Figs. 1–3: Burrill Lake, NSW (C.143092). |
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