Isospora erinacei Yakimoff and
Type host: Erinaceus
europaeus Linnaeus, 1758, Eurasian hedgehog.
Type locality: EUROPE: Russia,
Polotzk District, Leningrad Zoo.
Geographic distribution: EUROPE:
Description of oocyst: Oocyst shape:
ovoid (unsporulated), cylindroid (sporoblast stage), spheroid
(sporulated); number of walls: 2;
wall thickness:unknown, but probably <1;
wall characteristics: outer layer colorless to yellowish, apparently
L x W: 30 x 26 (28-34 x 23-27) for ovoid-cylindroid forms (no measurements
given for spheroid form);
L/W ratio: 1.15;
Distinctive features of oocyst: change in shape during
Description of sporocysts and
Sporocyst shape: ovoid;
L x W: 14.6 x 9.8-12.2;
SB: present (?);
SP: without a distinct RB, although this was not stated in the original
Distinctive features of sporocyst: pointed at one end and do not
fill the space within the oocyst; SP lack RB, are very short and
do not fill sporocyst.
Prevalence: 1 of 34 (3%).
Prepatent and patent periods:
Site of infection: Unknown. Oocysts
recovered from feces.
Materials deposited: None.
Remarks: The description of this
species is only marginally useful; it is retained as valid only
because some measurements and an original line drawing of a
sporulated oocyst were included. However, the original authors
reported the shape to vary greatly during sporulation from
distinctly ovoid to cylindroid to
spheroid when sporulated, but gave no measurements
for the spheroid form. It is possible that the spheroid forms
represented end-on views of the ovoid/cylindroid forms or even a
different species. Whichever the case, the sporulated oocyst has
no mensural data. It should be noted that the original line
drawing by Yakimoff and Gousseff (1936) is not drawn to the scale
of the measurements they provided; thus, we have redrawn the
sporulated oocyst to the scale of their measurements.
Also, Yakimoff and Gousseff (1936) mentioned the presence of SR,
but did not include it in their line drawing. Glebezdin and
Kolodenko (1969) said they found this species in hedgehogs in
Turkmenia. The oocysts they measured were 31.9 x 27.7 (26-35 x
25.5-29) and sporocysts were 13.6 x 10.3 (9.5-14.5 x 7.5-12).
Unfortunately, they did not give a line drawing or a
photomicrograph. Golemansky (1979) also found this species in 1/3
E. europaeus from the Sreburna Reserve, Bulgaria; the oocysts
measured 24 x 18. Glebezdin (1985) also reported finding I.
erinacei in hedgehogs (H. auritus ?) from southeastern
Turkmenestan but, again, this seems unlikely.
Yakimoff and Gousseff (1936); Glebezdin and
Kolodenko (1969); Golemansky (1979); Glebezdin