Do Male and Female Mussels Have Predictable Size Characteristics?

Elaine Langone Center, Terrace Room

Freshwater mussels are vastly understudied group of animals and as a result, basic life history characteristics are unknown for many species. In some species, gravid females display a deceptive lure made from part of its mantle, but unless the female is displaying the lure, it is difficult to quickly and accurately determine the sex of mussels based on their external morphology. This study determines the relationship between sex and morphology of Lampsilis cariosa and Eliptio complanata, two species native to the Susquehanna River. Using live mussels, samples of gonadal fluid were extracted from the visceral mass and examined to determine the sex of each individual. These data were then compared to three measurements of the corresponding shell: length, width, and girth. Determining the sex of live animals has important implications for future studies of mussel biology, begging questions related to their reproduction, demography, and population distribution.