Malacological Society of Australasia

Molluscan Research

Volume 19, Issue 2: 19 November 1998

Population genetic structure of the muricid gastropod Lepsiella vinosa in Gulf St Vincent, South Australia

Lianos Triantafillos *, **, Stephen Donnellan *** and Alan J. Butler *, ****

* Department of Zoology, University of Adelaide, North Terrace, Adelaide, SA 5000. ** Present address: South Australian Aquatic Science Centre, GPO Box 120 Henley Beach, SA 5022. *** South Australian Museum, Division of Natural Science, North Terrace, Adelaide, SA 5000. **** Present address: CSIRO Division of Marine Research, GPO Box 20, North Beach, WA 6020.

Allozyme electrophoresis was used to examine the population genetic structure of the marine gastropod Lepsiella vinosa, which produces benthic egg capsules with crawling juveniles. Samples of L. vinosa, taken from five locations along the coast of Gulf St Vincent, South Australia, including replicate samples within three of the locations, were examined for allozyme variation at four polymorphic loci (Acon-1, Got, Gpi and Lap). Genotypic frequencies were consistent with expectations under conditions of Hardy-Weinberg equilibrium. Genetic divergence between samples separated by only 500 m was small, in contrast to the great divergence found between samples separated by more than 10 km. This degree of genetic divergence (FST = 0.200 + 0.073; Nei's D mean = 0.071) indicated low gene flow (Nem = 1.08 immigrants per generation) over distances > 10 km. The data are consistent with a 'discrete subpopulation model'.
Key words: population, genetic structure, Lepsiella vinosa, South Australia

pp. 31-42.