Gonadal cycle of Corbicula fluminea (Bivalvia: Corbiculidae) in Pampean streams (Southern Neotropical Region)

DAMBORENEA, CRISTINA; CAO, LUCIANA; DARRIGRAN, GUSTAVO; PENCHASZADEH, PABLO E.

PLOS ONE

PUBLIC LIBRARY SCIENCE

Año: 2017 vol. 12

1932-6203

Corbicula fluminea is an aggressive invasive species of bivalve that arrived into the RõÂo dela Plata River between the late 60´s and early 70´s, and dispersed widely throughout theNeotropical region, evidencing a great adaptive flexibility to different environmental conditions.This species is a functional hermaphrodite with larval incubation inside the inner demibranch.Despite its widespread distribution, there are no previous studies of completegonadal histology and reproductive cycle for this species in the Neotropical region. In thisstudy, the reproductive dynamics of C. fluminea in a temperate region, the Santa CatalinaPampean stream, Argentina, is described. Samples of 20±30 individuals were collectedmonthly from April 2003-April 2005 and processed using traditional histological techniques.During the two years of this study, seven spawning events were recognized. Three majorspawns occurred in spring and summer, and other four minor ones during summer andautumn. Events of oocyte recovery were observed after spawning. A high number of incubatingindividuals was detected. The results stressed the difficulty of identifying a particularpattern of gamete release and of spawning behaviour in this invasive species, especiallywhen inhabiting an unstable environment.