Isospora concentrica McQuistion &
Type host: Dendrocolaptes certhia
(South American woodcreeper)
Other hosts: Dendrocolaptes certhia
Type locality: SOUTH AMERICA:
Ecuador, Provincia de Sucumbios, Imuya Cocha, 0º 34' S, 75º 17'
W, 200 m elev.
Geographic distribution: SOUTH
Description of oocyst: Oocyst shape:
ovoid; number of walls: 2 wall thickness: ~2.0; wall
characteristics: smooth, colorless outer layer with darker inner layer; L
x W: 26.9 x 22.7 (21-25 x 24-30); L/W ratio: 1.2 (1.0-1.4); M: absent; OR:
absent; PG: 1-2 present. Distinctive features of oocyst: lack of M &
Description of sporocysts and
sporozoites: Sporocyst shape: ovoid to ellipsoid; L x W: 17.2 x
11.0 (9-12 x 15-18); L/W ratio: 1.6 (1.4-1.7); SB: present, square or
present, ovoidal or bubble-shaped, located beneath the SB, but usually
lying to the left or right of the vertical axis; PSB: absent; SR: present;
SR characteristics: compact, usually slightly ovoid and composed of
uniform fine granules; SP: vermiform, ~15-16 x 3, with an round to
slightly oblong shaped posterir RB, a large circular nucleus and
the anterior half marked with concentric lines or grooves, randomly
arranged in sporocyst.
Distinctive features of sporocyst: unusual SP.
Prevalence: 2 of 5 (40%) D.
c. radiolatus and 1 of 1 (100%) D. c. columbianus.
Sporulation: Exogenous. Oocysts were
stored in 2.5% (w/v) aqueous potassium dichromate solution at
ambient temp. prior to examination.
Prepatent and patent periods:
Site of infection: Unknown.
Oocysts found in feces.
Materials deposited: Phototype and
formalin-preserved oocysts, USNPC #83243.
Remarks: This species has not been
reported since its original description.
Reference: McQuistion & Capparella