Isospora crotali in the Florida diamond-back rattlesnake.

Abstract

SYNOPSIS. An isosporan morphologically identical to Isospora crotali (Triffitt), 1925, was found in fecal material from one of six Florida diamond‐back rattlesnakes, Crotalus adamanteus. It is the only coccidian parasite found in a survey of over 200 feral snakes, including individuals from 4 families, 43 genera and 65 species. The endozoic sexual phases of the life‐cycle occur in the epithelial cells of the jejunum of the snake, as does formation of oocyst and sporocyst. Sporozoite formation occurs ectozoically, the sporulation time being 17 hr from onset of sporoplasmic fission, with a range of 13 hr. A survey of the literature indicates that I. crotali is probably the same species as the later described I. dirumpens Hoare, 1933, which has a widespread geographic distribution in diverse species of snakes. Other organisms probably synonymous with I. crotali include I. fragilis, I. laverani, I. lenti, and I. naiae. Reports of isosporan infections in snakes are few, particularly in the feral animals.