Type host: Macaca radiata (I. Geoffroy, 1812), Bonnet macaque.

Other Hosts: None reported to date.

Type Locality: ASIA: India, Zoological Gardens, Delhi.

Geographic distribution: ASIA: India, Zoological Gardens, Delhi.

Description of oocyst: Oocyst shape: subspheroid; number of walls: 2; wall characteristics: outer wall yellow-brown; inner, blue; L x W: 19.5-25 x 17-20; M: absent; OR: absent; PG: absent; Distinctive features of oocyst: very similar in size and shape to I. cebi except that this species has a 2-layered wall.

Description of sporocysts and sporozoites: Sporocyst shape: ovoid; L x W: 13-16 x 9-11; SB: present; SB characteristic: small; SSB: absent; PSB: absent; SR: present; SR characteristics: dark granules in a mass at 1 end of sporocyst; SP: contain 2 RB each. Distinctive features of the sporocyst: only 1 of 2 Isospora described from primates to have SB.

Prevalence: Unknown.

Sporulation: Unknown.

Prepatent and patent periods: Unknown.

Site of infection: Unknown. Oocysts recovered from feces.

Material deposited: None.

Remarks: These oocysts were described by Bhatia et al. (1972) from 1 M. radiata, captive in the Delhi Zoo, but they didn't name it for "lack of sufficient material." Although they included a line drawing, and qualitative/quantitative features distinguish this form from other Isospora spp. described to date from primates, we also are reluctant to attach a species name because its size, shape and other features resemble isosporan oocysts of avian origin. Thus, it may be a pseudo-parasite that was just passing through the gut of the macaque when its feces were collected.

Reference: Bhatia et al. (1972).