Scinax Wagler 1830

Duszynski, Donald W., Bolek, Matthew G. & Upton, Steve J., 2007, Coccidia (Apicomplexa: Eimeriidae) of amphibians of the world, Zootaxa 1667 (1667), pp. 1-77 : 33

Host genus Scinax Wagler 1830

(91 spp.)

Isospora cruzi Pinto and Vallim 1926 ( Fig. 17)

Type host: Scinax crospedospilus (Lutz 1925) (syn. Ololygon crospedospila [Lutz 1825] Fouquette and Delahoussaye 1977), Campo Belo snouted treefrog.

Other hosts: Scinax fuscovarius (Lutz 1925) , Snouted treefrog, Scinax nasicus (Cope 1862) , Lesser snouted treefrog, Scinax ruber (Laurenti 1768) , Red snouted treefrog.

Type locality: SOUTH AMERICA: probably Brazil .

Geographic distribution: SOUTH AMERICA.

Description of sporulated oocyst: Oocyst shape: elongate-ellipsoidal, asymmetrical, being more pointed at one end than the other (line drawing, Carini 1936); oocyst wall: 1 thin layer (line drawing), smooth; L x W: 20.7 x 17.2 (20–22 x 17–18); L/W ratio ~1.2; M, OR, PG: all absent. Distinctive features of oocyst: asymmetrically ellipsoidal, more pointed at one end than at the other.

Description of sporocyst and sporozoites: Sporocyst shape: subspheroidal; L x W: 14 x 13.8 ( Pinto & Vallim 1926) or 14 x 10 ( Carini 1936); SB, SSB, PSB: all absent; SR: present; SR characteristics: compact spheroidal mass of large and small granules, ~6–7, usually confined to one end of sporocyst (line drawing); SZ: sausage-shaped without visible RB or N (line drawing). Distinctive features of sporocyst: subspheroidal shape.

Prevalence: Not given.

Sporulation: Presumably exogenous.

Prepatent and patent periods: Unknown.

Site of infection: Near the tips of the villi in the small intestine (line drawing).

Endogenous development: Mature meronts, spheroidal, 16–20, with 8–12 merozoites, each irregularly triangular, that assume the shape of a small rosette; each merozoite is 6–8 x 4–5. Microgametocytes are spheroidal, 15–18 wide, with each microgamete ~1.5 wide. Macrogamonts are spheroidal to ovoidal, 18–20 x 16– 18, with heavily granulated protoplasm.

Pathology: Unknown.

Materials deposited: None.

Remarks: Pinto and Vallim (1926) found oocysts in the feces of several species of South American tree frogs, presumably from Brazil. Their oocysts were subspheroidal to ellipsoidal (line drawing), 20.7 x 17.2, with subspheroidal sporocysts, 13.8 x 14. Pinto and Vallim (1926) provided a line drawing of an unsporulated oocyst and a second drawing of an oocyst with 2 sporocysts filled with large globules, but there was no mention whether these were undeveloped sporocysts or if they were packed with a large SR. It was not until 1936 when Carini again found this species in S. ruber and documented that the two sporocysts actually had 4 SZ each. Carini (1936) also fixed some frog intestinal tissue for histological sections and described several of the endogenous stages.