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TRIPHORIDAE |
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Obesula albovittata (Hedley, 1903) Description: Shell very small, sinistral. Protoconch planktotrophic, of 4½-5¼ whorls, with a spiral thread and dense axial riblets.. Teleoconch whorls with 4 beaded spiral cords and axial costae; spirals 1 and 3 start immediately after protoconch, spiral 2 on about 3rd teleoconch whorl. By penultimate whorl, spirals 1 slightly stronger than spirals 2 and 3. Spiral 4 slightly exposed on all whorls. Another 2 spirals on base (numbered 5 and 6); spiral 5 weakly nodulose, spiral 6 smooth. Axial costae number 16-20 on penultimate whorl. Outer lip of aperture flared, anterior siphonal canal short, posterior canal a simple triangular notch. Colour of protoconch brown; teleoconch whorls with spiral 1 white with brown line around bottom edge, remainder of whorl fawn; base brown. Size: Adult shells 2.5 - 5.2 mm in length. Distribution: Endemic to Australia: Sydney, NSW, southwards and around southern Australia, to south-western WA. Habitat: Intertidal and subtidal down to 165 m, and in beach washup. Moderately common. Comparison: This species is distinctive because of the colouration: brown protoconch and base, teleoconch whorls fawn with thin brown line on spiral 1. Synonymy: A previously recognised synonym is Notosinister alborda Laseron 1954. Figs. 1, 2: Kurnell, NSW (C.116193) |
Copyright Des Beechey 2015