Strigea magniova Dubois, 1988

Lunaschi, Lía I. & Drago, Fabiana B., 2006, Strigeid parasites of the roadside hawk, Buteo magnirostris (Aves: Falconiformes), from Argentina, Zootaxa 1106, pp. 25-33 : 29

Strigea magniova Dubois, 1988 ( Fig. 3 )

Site of infection: small intestine.

Material deposited: in Helminthological Collection MLP 5507. Prevalence: 2 of 4 (50%).

Intensity of infection: 3.5 (2–5).

Description

Based on 7 specimens. Body distinctly bipartite, division into fore­ and hindbody accentuated; 2.103–2.476 mm (2.302) in total length. Forebody cup­shaped, 464–648 x 367–478 (531 x 427). Hindbody 3–4 times longer than forebody, 1.615–1.860 x 0.329– 0.445 mm (1.779 x 0.396). Ratio of hindbody length to forebody length 2.8–3.8 (3.4). Tegument smooth. Oral sucker subterminal 44–80 x 48 –68 (56 x 57). Ventral sucker immediately posterior to the oral sucker, 58–72 x 68 –78 (64 x 72). Suckers width ratio 1– 1.5 (1.2). Holdfast organ lobes reaching to anterior margin of forebody, compact proteolytic gland at base of forebody. Prepharynx absent; pharynx small, 36–48 x 41 –47 (43 x 43); intestinal caeca reaching into post­testicular region. Ratio of pharynx length to oral sucker length 0.6–0.9 (0.8).

Testes tandem, large, asymmetrical and occupying whole width of hindbody; anterior testis 136–314 x 250–490 (238 x 353) curved a horseshoe­like; posterior testis 240–294 x 314–466 (274 x 373). Ovary reniform, 92– 95 x 107–184 (94 x 146). Laurer’s canal short. Mehlis’ gland intertesticular. Vitellarium follicular, densely distributed in both parts of body; in forebody reaching anterior end; in hindbody, occupying its whole width in preovarian region and extending dorsally to copulatory bursa. Vitelline reservoir postovarian. Uterus ventral containing 13–33 (21) large eggs, 109–128 x 57 –72 (118 x 67). Copulatory bursa with genital cone delimited from body parenchyma and surrounded by muscular ring, 322–391 x 288–362 (356 x 328). Genital pore terminal. Excretory vesicle and pore not seen.

Remarks

This species was described by Dubois (1988) from the roadside hawk, Buteo magnirostris , from Paraguay. These specimens differ from those described in the present study by having a smaller body size (1.32 mm), ovary (52­65 x 60 ­80) and testes (anterior testis 120–160 x 130–195; posterior testis 130–150 x 140–220). However, the ratios of hindbody to forebody length, pharynx to oral sucker length, suckers width and size of eggs, are similar.

The present report has enabled us to augment the original description with new morphometrical data of parasites recovered from the type host. This report represents a new geographical record from Argentina.

Figures

FIGURES 1 – 5. Strigeids from Buteo magnirostris from Argentina. 1. Ophiosoma microcephalum, entire worm, ventral view, scale­bar: 200 m. 2. O. microcephalum, enlarged ventral view of forebody, scale­bar: 100 m. 3. Strigea magniova, entire worm, ventral view, scale­bar: 200 m. 4. Strigea falconis brasiliana, entire worm, ventral view, scale­bar: 200 m. 5. S. f. brasiliana, enlarged view of terminal genitalia, scale­bar: 100 m.