THE MORPHOLOGY OF TOXOGLOSSAN GASTROPODS LACKING A RADULA, WITH A DESCRIPTION OF NEW SPECIES AND GENUS OF TURRIDAE

The morphology of some deep-sea Turridae lacking radulae wasstudied. The main features of their digestive system are theabsence of a radula sac, venom and salivary glands and the reductionor absence of a proboscis. A new genus Teretiopsis including3 new species and T. thaumastopsis (Dautzenberg and Fischer,1896) is described. On the basis of differences of the digestivesystem when compared with other turrids lacking radulae themonotypical subfamily Taraninae Casey, 1904 new status (typegenus Taranis Jeffreys, 1870) is considered. It is shown thatthe process of radula reduction has occurred independently indifferent phylogenetic lines of Toxoglossa—the subfamiliesDaphnellinae and Taraninae among Turridae and the family Terebridae. (Received 8 August 1988; accepted 20 December 1988)     

SEXUAL DIMORPHISM IN THE APERTURAL NOTCH OF A NEW SPECIES OF GEMMULA (GASTROPODA: TURRIDAE)

The presence of a ‘tertiary’ apertural ‘notch’has been recorded in some species of Gemmula (subfamily Turrinae)and in Aforia circinata (Turriculinae). Studies of a large seriesof the new species Gemmula lordhoweensis confirms the presenceof the notch in adult females. The presence of the notch maybe connected with the processes of fertilization or oviposition. (Received 23 March 1990; accepted 25 June 1990)     

TAXONOMIC REEVALUATION OF GEMMULOBORSONIA SHUTO, 1989 (GASTROPODA: CONOIDEA), WITH A DESCRIPTION OF NEW RECENT DEEP-WATER SPECIES

The genus Gemmulobonorua Shuto, 1989, until now known only fromUpper Miocene-Lower Pleistocene deposits of the Tethys, is recordedin Recent faunas, with five new bathyal species from New Caledonia,Indonesia, Mozambique Channel, and the Philippines. Radularmorphology indicates that Gemmuloborsorua belongs to the subfamilyTurnnae, and not to Borsoruinae, where it had been allocatedbased on shell morphology. Columellar pleats, which have longbeen considered a synapomorphy of the borsornid group of genera,have thus been acquired independently in the Turnnae. The consequenceof this finding is that the current (sub)fanuly allocation ofsome genera, based on shell characters only, may need reevaluation. (Received 21 July 1995; accepted 8 August 1995)