Spirorbis

Spirorbis is a genus of very small polychaete worms, usually with a white coiled shell. Members of the genus live in the lower littoral and sublittoral zones of rocky shores. Spirorbis worms usually live attached to seaweeds, but some species live directly on rocks, shells or other hard substrates. Spirorbis was once thought to have a fossil record extending back into the Early Paleozoic, but now all pre-Bathonian spirorbins are known to be microconchids. The earliest members of genus appeared in the Miocene, but Oligocene finds may
also be possible. The genus contains the following species:Spirorbis borealis Daudin, 1800Spirorbis corallinae De Silva and Knight-jones, 1962Spirorbis cuneatus Gee, 1964Spirorbis granulatusSpirorbis incongruusSpirorbis inornatus L'hardy and Quievreux, 1962Spirorbis knightjonesi Desilva, 1965Spirorbis lineatusSpirorbis marioni Spirorbis mediusSpirorbis moerchiSpirorbis nakamuraiSpirorbis quadrangularisSpirorbis quasimilitaris Bailey, 1970Spirorbis rupestris Gee and Knight-jones, 1962Spirorbis semidentatusSpirorbis similisSpirorbis spirorbis Spirorbis steueri Sterzinger, 1909Spirorbis tridentata Levinsen, 1883Spirorbis variabilis

''Spirorbis violaceus''