Bathyal Nukumaruan Mollusca from Oaro, southern Marlborough, New Zealand

Abstract

More than 100 mollusk spp. are listed from Nukumaruan (Late Pliocene or Early Pleistocene) siltstone on the summit of the first hill south of Oaro, Hundalee Hills, southern Marlborough. Most species are part of the living bathyal mollusk an fauna of canyons off eastern South Island; the siltstone was evidently deposited in 600-800 m of water. Falsilunatia, Penion benthicolus Dell, P. fairfieldae (Powell), Cominella (Eucominia) alertae (Dell), C. mirabilis cantuariensis (Dell), Euthrenopsis otagoensis Powell and Volutomitra (Latiromitra) are reported as fossils for the first time. The fauna is dominated by the buccinids Cominella nassoides otakauica Powell, an abundant living taxon and Aeneator (Aenaetor) elegans (Suter), a species only recently recognized in the livin fauna. The locality is probably the type locality of A. elegans and F. ambigua (Suter), the latter an earlier name for the living F. powelli Dell. New species of Mesoginella (Sinuginella), Paracomitas (Macrosinus), Spendrillia and Neoguraleus (Fusiguraleus) are named. S. armata Powell, S. kingmai Marwick, S. majorina sp. nov., S. zeobliqua sp. nov. and P. (M.) haumuria sp. nov. are recorded living off eastern South Island [New species also include: M. (S.) megalabra and N. (F.) gracilicostus.].