THE COCCIDIA (APICOMPLEXA, EIMERIIDAE) OF CAUDATA (AMPHIBIA), WITH DESCRIPTIONS OF 2 NEW SPECIES FROM NORTH-AMERICA

Over 300 caudate Amphibia were surveyed for coccidia in North America. Two new species of coccidia (Apicomplexa: Eimeriidae) are described. Oocysts of Eimeria opacum sp.nov. from Ambystoma opacum are spherical to subspherical, rarely ellipsoidal, 29.5 x 28.1 (27-32 x 22-31) pm, a nd have a shape index (length/width) of 1.05 (1.0-1.4). A micropyle, o ocyst residuum, and polar granule are absent. Sporocysts are ellipsoid al to kidney-bean shaped, 17.4 x 9.1 (16-21 x 8-11) mu m, with a shape index of 1.92 (1.6-2.3). Sporocysts are unusual in that they are enca sed in a second, more fragile wall that thins to form membranes at the poles; Stieda and substieda bodies are absent. Oocysts of Isospora hi ghtoni sp.nov. from Plethodon albagula are spherical, rarely subspheri cal, 22.9 x 22.8 (21-24 x 21-24) mu m, with a shape index of 1.0 (1.0- 1.04). A micropyle and polar granule are absent, but a delicate oocyst residuum was noted in 13/40 (33%) of the oocysts. Sporocysts are elli psoidal, 16.6 x 11.1 (14.5-17.5 x 10.5-12) mu m, with a shape index of 1.5 (1.4-1.6); Stieda and substieda bodies are present. In addition t o the species described herein, a taxonomic summary is provided of the known coccidia from Caudata, with the species E. nipponensis sp.nov., E. pyrrhogaster sp.nov., and E. saitamaensis sp.nov. assigned to prev iously reported coccidia erroneously assigned to named species.