Isospora nagna McQuistion &
Type host: Dendrocolaptes
certhia radiolatus (South American woodcreeper)
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
29.7 x W: 23.4 x 24.9 (23-26 x 26-31); L/W ratio: 1.2 (1.1-1.3); M:
absent; OR: absent; PG: present. Distinctive features of oocyst: lack of M
Description of sporocysts and
sporozoites: Sporocyst shape: ovoid; L x W: 15.8 x 12.6 (11-14 x
15-20); L/W ratio: 1.3 (1.1-1.6); SB: present, broad, dome-like; SSB:
inconspicuous, with a wavy lower surface and located directly below the
SB, but slightly to the left or right of the vertical axis; PSB: absent;
SR: present; SR characteristics: uniform, fine granules in a
consolidated, lobate, well defined cluster ~5.5-6; SP: sausage-shaped,
~14 x 2.5-3, with an oval posterior RB (~6 x 3), a slightly smaller ovoid
anterior RB (~5 x 2.5), and a round, less distinct, centrally located
features of sporocyst: the large SR.
Prevalence: 1 of 2 (50%).
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 #83242.
Remarks: This species has not been
reported since its original description.
Reference: McQuistion & Capparella