Larval Digenean Community Parasitizing the Freshwater Snail, Chilina dombeyana (Pulmonata: Chilinidae), in Patagonia, Argentina, with Special Reference to the Notocotylid Catatropis chilinae.

FLORES, V. R.; SEMENAS, L. G.

JOURNAL OF PARASITOLOGY

American Society of Parasitologists

Año: 2008 vol. 94 p. 305 - 313

0022-3395

The objective of this research was to describe the structure of larval digenean communities in the freshwater snail Chilina dombeiana in an Andean oligotrophic Patagonian lake, Lake Mascardi. A total of 1,923 snails were collected during two sampling periods. Specimens were examined, and eight digenean species were found, all with allogenic life cycles. The snail infracommunities nearly always occurred as single-species infection, distributed mainly in the hepatopancreas. The double infections (0.2 %) were always prepatent, and involved a schistosomatid and a notocotylid, Catatropis chilinae. The total percentage of infection, the prevalence of C. chilinae and add up of other species prevalence significantly increased with snail size. Catatropis chilinae was the dominant species across all months and snail size classes. Maximum richness (6) was reached in intermediate snail size class (16-18 mm). Both diversity indices, the Shannon-Wiener Index and the reciprocal of the Simpson Index, increased with snail size only during the second sampling period. No robust evidence of antagonistic interactions in digenean community of C. dombeiana from Lake Mascardi was found.