Facultative and obligate symbiotic associations of Pomacea canaliculata (Caenogastropoda, Ampullariidae)

VEGA, ISRAEL ANÍBAL, DAMBORENEA, CRISTINA, GAMARRA-LUQUES, CARLOS, KOCH, EDUARDO , CASTRO-VAZQUEZ

BIOCELL

IHEM-CONICET

Lugar: Mendoza; Año: 2006 vol. 30 p. 367 - 375

0327-9545

P. canaliculata is characterized by the great diversity of the symbionts it lodges. This includes both epibiotic and endosymbiotic associations with Eukarya and Bacteria. The epibiotic community is composed by a predominantly algal mat (Chlorophyta, Chysophyta) where a diversity of both sessile and motile protists (Ciliates; Euglenophyta) and animals (Rotifera, Nematoda, Hirudinea, Oligochaeta and Diptera larvae). Eukaryotic endosymbionts may be found in the mantle cavity (Platyhelminthes – both Turbellaria, and Trematoda-, Copepoda and Acari), in the haemocoel and connective tissue (Trematoda; Copepoda), and in the gut (Ciliata; Rotifera; Nematoda; Trematoda). Besides an abundant heterotrophic bacterial biota in the intestinal lumen, P. canaliculata bears a cyanobacterial symbiont within columnar cells of the midgut gland’s alveoli. As compared with all the other symbionts found, this cyanobacteria is the only one found as an obligate symbiont to P. canaliculata, which apparently reproduces within alveolar columnar cells, and it is freed into the intestinal lumen, and from there into the external environment, where it may survive for years.