Pseudepidalea Frost et al. 2006

Duszynski, Donald W., Bolek, Matthew G. & Upton, Steve J., 2007, Coccidia (Apicomplexa: Eimeriidae) of amphibians of the world, Zootaxa 1667 (1667), pp. 1-77 : 26

Host genus Pseudepidalea Frost et al. 2006

(11 spp.)

Isospora brumpti Lavier 1941 ( Fig. 7)

Synonym: Diplospora brumpti ( Lavier 1941) Grasse, 1953 .

Type host: Pseudepidalea viridis (Laurenti 1768) , Green toad.

Other hosts: None to date.

Type locality: ASIA: Syria .

Geographic distribution: ASIA: Syria, Turkmenistan.

Description of sporulated oocyst: Oocyst shape: ovoidal to ellipsoidal (line drawing); number of walls: 1 (line drawing); wall thickness: 0.3–0.5; wall characteristics: colorless; L x W: 24 x 16 (20–25 x 11–17); L/W ratio: 1.5; M, OR, PG: all absent. Distinctive features of oocyst: colorless, thin, fragile wall that collapses around the sporocysts and ruptures and vanishes soon after sporulation.

Description of sporocyst and sporozoites: Sporocyst shape: ellipsoidal; L x W: 15–19 x 10–14; L/W ratio: unknown; SB, SSB, PSB: all absent; SR: present; SR characteristics: granular body situated between SZ; SZ: banana-shaped, 13 x 3, lying head to tail, partly obscured by SR. Distinctive features of sporocyst: large granular SR.

Prevalence: Unknown.

Sporulation: Usually 24–48 h or less; some oocysts in fresh feces already have 2 sporoblasts.

Prepatent and patent periods: Unknown.

Site of infection: Within the first segments of the small intestine, but can also extend down the full length of the intestine.

Endogenous stages: Intracellular forms occupy a position between the center and the top of the epithelial cells. When a merozoite first enters a cell it is ~14 x 3; after rounding up and nuclear fragmentation it gives rise to 12–14 arched merozoites with pointy ends, which measure 12–14 x 3 and are tightly packed together. Frequently, one finds in a single vacuole up to 50 older merozoites, which appear to be segregating into several groups. Early microgamonts are indistinguishable from immature meronts, but as they mature they are easily distinguished by the N divisions that are happening at their surface. Lavier (1941) suggested that he saw 6–8 elongated chromosomes at this stage. By the time microgametogenesis is completed, the microgamont is ovoidal, and measures ~20 x 12. Lavier (1941) said that the macrogamont stays elongated for a long time (gregariniforme) while increasing in size, sometimes exceeding that of the oocyst. Mature macrogamonts are spheroidal and highly granular.

Pathology: Unknown.

Materials deposited: None.

Remarks: According to Pellérdy (1974), Lavier (1941) was unable to infect B. bufo (= B. vulgaris ) with (sporulated?) oocysts. Ovezmukhammedov and Annakuliyeva (1973) said they found this species in 4 of 46 (8.7%) P. viridis from the Ashkhabad and Tedzlien regions of Turkmenistan, but not in 121 Pelophylax ridibunda (Pallas 1771) . The oocysts they measured were 20.9 x 16.5 (19–22 x 13.5–19), the sporocysts were 11.5 x 9.5 (11–13.5 x 8–11), and the sporozoites were 8.8 (8–11) x 2.7. These oocysts were thus shorter and wider than those in the original description (and, therefore, had a smaller L/W ratio, a feature that often is quite constant in the oocysts representing a single species) with shorter sporozoites. Thus, it is not clear whether Ovezmukhammedov and Annakuliyeva (1973) were looking at a different species of Isospora or if these size differences in the sporulated oocysts was just a geographic variant.