No abstract

Habitat selection of common skipper frog [Euphlyctis cyanophlyctis (Schneider, 1799)] was studied by a sampling (covering all the three seasons) of data collection on six abiotic (size and depth of water body, air and water temperature, dissolved oxygen and free carbon dioxide) and three biotic (plant species richness, zooplankton species richness and zooplankton density) factors of three ponds in Chittagong, Bangladesh. The discriminant analysis, cluster analysis and paired t-test of total data revealed that the three water bodies functioned as separate systems. Of the nine factors, only four (AT, WT, FCO2 and Zp_den) had individual significant influence on the frog at least at one of the ponds. However, the maximum R 2 value (0.712, p < 0.001) indicates that at least some important factors were not included in the investigation.

In all, 13 parasite taxa -eight cercariae, three nematodes, one rhabdocoel and one aspidogastrean -were recorded from 205 out of the 642 snails autopsied. Of the carcariae, xiphidiocercous was the most diversified (five taxa), followed by the echinostome (two) and the furcocercous (one). Infection by the nematodes, though rather poor in diversity, was much higher (23.99%) than that (12.15%) by the developmental stages of Trematoda. The rhabdocoel and the aspidogastrean were minor infestors having 1.56% and 2.80% prevalence, respectively. Bellamya bengalensis was the most abundant host, had the highest parasite diversity (12 taxa) and also the highest prevalence of infection (51.59%).Though the second highest abundant host, Paludomus blanfordiana had the least parasite diversity (only an oxyurid nematode) and a very low prevalence (2.04%) as well. Brotia costula, the big strong snail harboured two taxa (a carcaria and a nematode), and also had a low prevalence (8.65%). The amphibious Pila globosa, though least abundant among the four hosts, had moderately high parasite diversity (four carcariae and two nematodes) and prevalence (40.26%).