Strigea falconis brasiliana Szidat, 1929

Lunaschi, Lía I. & Drago, Fabiana B., 2006, Strigeid parasites of the roadside hawk, Buteo magnirostris (Aves: Falconiformes), from Argentina, Zootaxa 1106, pp. 25-33 : 30-31

Strigea falconis brasiliana Szidat, 1929 ( Figs. 4–5 )

Site of infection: small intestine.

Material deposited: in Helminthological Collection MLP 5506. Prevalence: 1 of 4 (25 %).

Intensity of infection: 2 (2).

Description

Based on 2 specimens. Body distinctly bipartite; 1.305–1.392 mm in total length. Forebody cup­shaped, 319–415 x 314–367 clearly separated from hindbody and covered with minute tegumental spines. Oral sucker subterminal, 76 x 55. Ventral sucker 152–162 x 71 –105. Suckers width ratio 1.9. Holdfast organ lobes reaching to anterior margin of forebody with compact proteolytic gland at base of forebody. Hindbody with tegument smooth, 2.1–3.4 times longer than forebody, 0.890–1.073 x 0.362–0.435 mm. Prepharynx short; pharynx well developed, 74 x 48; intestinal caeca reaching copulatory bursa. Ratio of pharynx length to oral sucker length 1.1.

Testes tandem, large, lobated, in the posterior middle hindbody; anterior testis 169– 227 x 174–190; posterior testis 197–217 x 179–241. Ovary reniform, 59– 68 x 101–107. Laurer’s canal short, opening in the dorsal surface in ovary­testicular region; Mehlis’ gland intertesticular. Vitellarium follicular, densely distributed in hindbody; in forebody reaching to ventral sucker; in hindbody occupying its whole width in preovarian region and extending dorsally to copulatory bursa. Vitelline reservoir intertesticular. Uterus with 3 and 5 large eggs, 82–88 x 48 –52. Copulatory bursa 183–241 x 215–226, with muscular ring (Ringnapf) well developed and genital cone, 128–167 x 129–143. Ratio of genital cone width to ovary width 1.2–1.4. Genital pore terminal. Excretory vesicle and pore not seen.

Remarks

Strigea falconis Szidat, 1928 is a cosmopolitan species including three subspecies: S. falconis falconis Viborg, 1795 , has a Holarctic and Ethiopic distribution, S. falconis mcgregori Tubangui, 1932 occurs in the Oriental region, and S. falconis brasiliana Szidat, 1929 in the Neotropical region. The latter subspecies was first reported, but not described, as Strigea falconis var. brasiliana by Szidat (1929) from specimens collected by Natterer in Buteo albicaudatus Vieillot , B. magnirostris , Herpetotheres cachinnans (Linnaeus) , Caracara plancus (Miller) and Spizaetus ornatus (Daudin) (Falconiformes) from Brazil. Pérez Vigueras (1944, 1955) described it as Strigea falconis from Buteo jamaicensis umbrinus Bangs from Cuba. Dubois (1968) redescribed it as Strigea falconis brasiliana on the basis of the specimens collected by Natterer, and Dubois and Macko (1972) reported it from Buteo platypterus cubanensis Burns from Cuba.

The specimens described by Dubois (1968) differ from those described in the present study by having a larger size (hindbody, 1.1–1.8 mm; oral sucker, 100–125 x 85 –115; ovary, 110–200 x 175–300; anterior testis 235 x 410; posterior testis 275–370 x 235–420; genital cone, 240–350 x 230–310), however, the egg size and the ratios of hindbody to forebody length and genital cone to ovary width, are similar. The smaller size of the two specimens described in this paper, relative to those described from Brazil, could be related to intraspecific variations in the developmental stage of the parasite.

Strigea falconis brasiliana differ from S. magniova by the presence of tegumental spines in the forebody and a well developed Ringnapf, by the distribution of the vitelline follicles in the forebody and by the size of its body, pharynx, ventral sucker and eggs.

The record of S. falconis brasiliana from B. magnirostris represents the first report of this parasite in Argentinean birds and has enabled us to augment the original description with new morphological and morphometrical data.

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.