Evaluation of conservation status, distribution, and reproductive characteristics of an endemic Gulf Coast freshwater mussel, Lampsilis australis (Bivalvia : Unionidae)

摘要

The southern sandshell, Lampsilis australis Simpson, 1900, is a rare freshwater mussel endemic to the Escambia, Yellow, and Choctawhatchee river drainages in Alabama and Florida. Laboratory observations confirmed L. australis as a superconglutinate producer. Superconglutinate and glochidial morphology are similar to those of other superconglutinate producers. The current distribution of L. australis, as determined from recent surveys (1995-2000) and field notes (1990-2000), is compared with its historical distribution as defined by museum collections and field notes made between 1900 and 1989. The current distribution of L. australis is reduced by 76% compared to its historical distribution, although L. australis was located at new sites in the recent surveys. Relative abundance of L. australis was low at all but two sites. Based on reproductive strategy, range reductions, low relative abundance, and potential threats within the Escambia, Yellow, and Choctawhatchee river drainages, we believe L. australis should be considered for protection under the Endangered Species Act.