DIFFERENCES IN DENSITY, SHELL ALLOMETRY AND GROWTH BETWEEN TWO POPULATIONS OF LIMNOPERNA FORTUNEI (MYTILIDAE) FROM THE RÍO DE LA PLATA BASIN, ARGENTINA

BONEL, N.; SOLARI, L. C.; LORDA J.

MALACOLOGIA

INST MALACOL

Lugar: Philadelphia; Año: 2012 vol. 56

0076-2997

The invasive freshwater mussel, the mytilid Limnoperna fortunei (Dunker, 1857), has agreat capacity for colonizing a wide range of aquatic environments because of its dispersalability, high fecundity and wide range of physiological tolerances. Most of the biological andecological studies of L. fortunei having been restricted to specific locations, there is a lackof comparative analyses among different habitats. In this investigation, we examined the differencesin larval density, density in settlement plates, shell allometry and growth betweentwo populations from the Río de la Plata basin, Argentina. One of the populations inhabiteda heavily polluted area, whereas the other a moderately polluted area. We predicted that thedensity and growth of the golden mussel would be lower in the heavily polluted environment,expecting therefore to find variations in shell allometry as a consequence of differences indensity and environmental conditions between the sites investigated. We accordingly foundthat the larval density, the density of settled individuals and the growth were lower in themore polluted environment. We also observed allometric differences because the individualsfrom the moderately polluted area with higher population densities were more elongated(i.e., with a higher shell length-to-width ratio). The golden mussel tolerates a wide rangeof environmental conditions and can survive in many polluted water bodies where otherinvasive species cannot. The findings presented here supports the idea that L. fortunei caninhabit heavily polluted environments, but at the expense of a significant decrease in itsbiologic potential.