Bothriogaster variolaris, (Fuhrmann, 1904)

Drago, Fabiana B., Lunaschi, Lía I. & Draghi, Regina, 2014, Digenean fauna in raptors from northeastern Argentina, with the description of a new species of Strigea (Digenea: Strigeidae), Zootaxa 3785 (2), pp. 258-270 : 267-268

Spaniometra variolaris ( Fuhrmann, 1904)

( Fig. 10 )

Syns. Bothriogaster variolaris Fuhrmann, 1904 ; Bothrigaster variolaris ( Fuhrmann, 1904) Dollfus, 1948; Ophthalmophagus variolaris ( Fuhrmann, 1904)

Host: Rostrhamus sociabilis (Vieillot) , snail kite (Accipitidae)

Site of infection: air–sacs.

Voucher specimens: MLP 6718, 6719.

Distribution and Hosts: This species was originally described by Fuhrmann, (1904) as Bothriogaster variolaris parasitizing R. sociabilis from South America. Later, it was reported in the same host in Brazil ( Travassos 1922), Cuba ( Perez Vigueras 1940, 1955) and USA ( Cole et al. 1995), and in Accipiter bicolor pileatus from Paraguay ( Masi Pallarés & Benítez Usher 1972).

Measurements: Based on 5 immature specimens. Body linguiform, 3.97–4.4 (4.2) mm long by 0.80–1.03 (0.95) mm wide. Mouth subterminal. Oral sucker absent. Ventral sucker round, immediately posterior to intestinal bifurcation, 126–130 (127) long by 133–145 (143) wide. Prepharynx 121–169 (145) long; pharynx slightly oval, 112–143(126) long by 107–126 (116) wide; esophagus 40–95 (69) long; ceca long, united near posterior extremity forming cyclocoel. Testes tandem, entire; anterior testis round, equatorial, 241–242 (242) long by 227–242 (235) wide; posterior testis subspherical, post-equatorial, 237–266 (250) long by 134–256 (214) wide. Ovary round, located anterior to posterior cecal union, 107–169 (141) long by 107–193 (146) wide.

Remarks: The morphological characters of the specimens here described agree with the descriptions of Perez Vigueras (1940, 1955), but they are smaller (3.97–4.4 mm vs. 6–7 mm) and have not reached sexual maturity. The specimens described by Masi Pallarés & Benítez Usher (1972) possess morphological and morphometric characters similar to our specimens. The life cycle of S. variolaris is unknown; however, considering the life cycle pattern of cyclocoelids, probably the snail kites become infected by eating snails that harbor metacencariae. The high densities of S. variolaris can cause airsacculitis and bronchitis, and probably the death of birds from USA (see Cole et al. 1995). However, in this study the infection intensity was relatively low compared with the studies in the northern hemisphere (22 vs. 40–225).

The finding of this cyclocoelid parasitizing R. sociabilis from Formosa Province represents the first record of the genus Spaniometra Kossack, 1911 in Argentina.

Figures

FIGURES 4 – 11. Digeneans from raptors. 4. Strigea proteolytica n. sp. from Buteogallus urubitinga, scale bar = 250 µm. 5. Strigea falconis brasiliana Szidat, 1929 from Caracara plancus, scale bar = 250 µm. 6. Neodiplostomum travassosi Dubois, 1937 from Buteogallus meridionalis, scale bar = 200 µm. 7. Tylodelphys brevis Drago & Lunaschi, 2008 from Busarellus nigricollis, scale bar = 100 µm. 8. Posthodiplostomum macrocotyle Dubois, 1937 from B. nigricollis, scale bar 200 µm. 9. Enlarged view of copulatory bursa of P. macrocotyle, scale bar 50 µm. 10. Spaniometra variolaris (Fuhrmann, 1904) from R. sociabilis, scale bar 500 µm. 11. Megalophallus deblocki Kostadinova, Vaucher & Gibson, 2006 from R. sociabilis, scale bar 100 µm. Abbreviations: B, body wall; Gc, genital cone; P, prepuce.