Type host: Tupaia glis modesta (J. Allen, 1906), Common tree-shrew.

Other hosts: None reported to date.

Type locality: ASIA: Vietnam, Quang Nam Province, 1.3 km N and 4.2 km S of Mt Sontra, (16º E 07' N, 108º E 15' E, elev. 500 m).

Geographic distribution: ASIA: Vietnam, Quang Nam Province, 1.3 km N and 4.2 km S of Mt. Sontra, (16º E 07' N, 108º E 15' E, elev. 500 m).

Description of oocyst: Oocyst shape: subspheroid to bluntly ellipsoid; number of walls: 2; wall thickness: outer 1.5-2, inner 1; wall characteristics: outer is knobby, brownish-yellow, thick and striated (bright field illumination); inner is yellow, refractile, and striated; L x W: 20.6 x 19.6 (18-24 x 16-23); L/W ratio: 1.05 (1.0-1.5); M: absent; OR: present; OR characteristics: eccentric mass composed of several large granules; OR L x W: 3-5; PG: absent. Distinctive features of oocyst: differs from those of E. ferruginea in shape, by being smaller, and having an OR that is granular rather than a single globule (Colley, 1970).

Description of sporocysts and sporozoites: Sporocyst shape: ovoid; L x W: 11.1 x 7.2 (8-14 x 6-10); L/W ratio: 1.5; SB: large, ~1/2 the width of sporocyst (in line drawing); SSB: absent; PSB: absent; SR: present; SR characteristics: compact mass of numerous coarse granules; SP: comma-shaped, about 6 x 3, without RB. Distinctive features of sporocyst: distinctive large, rounded SB. Prevalence: 4/10 (40%).

Sporulation: Exogenous. Oocysts sporulated within 5 days in 3% aqueous potassium dichromate solution at 22-42ºC.

Prepatent and patent periods: Unknown.

Site of infection: Both meronts and gamonts were found in endothelial cells in the terminal ileum, anterior to ileo-cecal valve. Meronts had only 8 merozoites. Developing parasites were seen on the luminal side of host endothelial cells displacing the N toward the basement membrane.

Material deposited: Apparently, the symbiotype host is in the U.S. National Museum (No. 356389; Collector's No. PFR 263). Slides of terminal ileum showing endogenous stages are deposited in the U.S. National Parasite Collection (USNPC), Beltsville, Maryland, USA, Nos. 23974, 23975.

Remarks: Colley (1970) compared E. modesta and E. ferruginea and believed they were different species.

Reference: Colley (1970); Van Peenen et al. (1967).