Type host: Sciurius anomalus.

Other Hosts: Sciurus vulgaris (?); S. vulgaris altaicus

Type locality: EUROPE: Yugoslavia: Serbia, Belgrade Zoo..

Description of oocyst: Oocyst shape: ellipsoidal; wall thickness: 1.5; layers: 1; outer layer texture: smooth; micropyle: absent; OR: absent; OR L x W: 27.5 x 17.5 (21-34 x 15-20); L/W ratio: 1.6 (1.4-1.8); PG: 0-2; . Distinctive features of oocyst: ellipsoidal shape with smooth, thick outer wall.

Description of sporocysts and sporozoites: Sporocyst shape: ellipsoidal; size: 11.9 x 6.9 (6-7.5 x 5-14); L/W ratio: 1.7 (1.5-2.1) SB: present; SSB: absent; PSB: absent; SR: present; SR characteristics: small to medium-sized granules dispersed between SZ; SP: lie head-to-tail, with 1 distinct posterior RB; N not visible. Distinctive features of sporocyst: none.

Material Deposited:Photosyntypes of sporulated oocysts deposited in the U.S. National Parasite Collection (USNPC), Beltsville, Maryland, No. 95336.

Remarks: Ryšavý and ?erná, (1979) speculated that this species, was first described in the Czech Republic by Jírovec (1942) who misidentified it as Eimeria sciurorum Galli-Valerio, 1922; however, the form described by Jirovich (1942) had oocysts that were 30-50 x 15-35, much too large to be E serbica. Ryšavý (1954) “described evidently the same species from the same host [species],” but also called it E. sciurorum (Ryšavý and ?erná,, 1979). Three years later, Pop-Cenitch and Bordjochki (1957) described and named E. serbica from S. vulgaris in Yugoslovia. Sporulated oocysts of E. serbica that we measured from S. anomalus are almost identical in shape (ellipsoidal) and size (21-34 x 15-20, mean 27.5 x 17.5) to those first described from the Eurasian red squirrel S. vulgaris from Yugoslavia (21-35 x 12-24, in Pop-Cenitch and Bordjochki, 1957). Additionally, sporocyst size and characteristics from the original description of E. serbica (7-8 x 12-13; SB and SR of “conspicuous dense dark small granules”) were similar to the sporocysts we found in S. anomalus (6-7.5 x 10.5-14, mean 6.9 x 11.9). This is the first record of an eimerian infecting the Caucasian tree squirrel. .

Reference:Couch et. al., 2005