Natural occurrence of Diplostomum sp (Digenea : Diplostomatidae) in adult mudpuppies and bullfrog tadpoles from the St. Lawrence River, Quebec

Adult mudpuppies (Necturus maculosus) and bullfrog tadpoles (Rana catesbeia na) infected with the eyefluke Diplostomum sp. in the lenses were collected from the St. Lawrence River. Quebec. Canada. Respective prevalence and mea n abundance of Diplostomum, sp. were 100% and 3.1 +/- 1.7 in Lake St. Franc ois, 58.3% and 1.5 +/- 1.8 in Lake St Louis. and 53.8% and 0.7 +/- 0.8 in L ake St. Pierre. No eyeflukes were observed in mudpuppies from the Richelieu River. Prevalence and mean abundance of Diplostomum sp. were significantly higher in mudpuppies from Lake St. Francois than in those from other sites . The high prevalence and abundance in Lake St. Francois may be because the regulated water levels may enhance snail intermediate host habitats. There was a significant negative correlation between mudpuppy length and number of eyeflukes Per host when samples were pooled From the 3 sites where Diplo stomum sp. was found. Mean length of infected mudpuppies from those 3 sites was significantly smaller than uninfected ones. Twenty-four (28%) of 86 mu dpuppies had cataracts associated with infections of eyeflukes. Prevalence and mean abundance of Diplostomum sp. in bullfrog tadpoles collected from L ake Sr. Pierre were 14.3% and 0.1 +/- 0.4 parasite per animal. much lower t han observed for mudpuppies from the same lake. Higher occurrence of eyeflu kes in mudpuppies compared with tadpoles is attributed to the greater age a nd more sedentary benthic nature of mudpuppies. This is the first report of amphibians naturally infected with Diplostomum sp. and only the second wit h eyeflukes in general.