Rhipidocotyle jeffersoni ( Kohn, 1970 ) Overstreet & Curran, 2002

Kohn, Anna & Fernandes, Berenice M. M., 2006, Redescription of Rhipidocotyle jeffersoni (Kohn, 1970) Overstreet & Curran, 2002 (Digenea: Bucephalidae), Zootaxa 1193 (1193), pp. 41-47 : 42-45

Rhipidocotyle jeffersoni ( Kohn, 1970) Overstreet & Curran, 2002

( Figs. 1–5)

Host: Salminus brasiliensis (Cuvier) , Characidae , “dourado”.

Site: Intestine.

Localities : Paraná River (locality: Guaira), 24°04’48”S, 54°15’21”W and its reservoir (hydroelectric power station of Itaipu — localities: Guaira and Santa Helena), Paraná State, Brazil, 24°51’37”S, 54°19’58”W .

Prevalence: 31% (eight of 26 fish examined); from 1991 to 1993 R. jeffersoni was was not found in fish examined.

Intensity: 2–12 parasites per infected fish.

Deposition of specimens: CHIOC, n o 30.523 a–e (holotype); 33.610 a–e, 33.928 a–l, 36.608 a–d and 36.609 a–b (vouchers) .

*Reservoir of the Hydroelectric Power Station of Itaipu. Description

Based on 21 newly­collected adult specimens, the holotype, and two paratypes specimens. Measurements are given in Table 1. Body spinose, small, broad, fusiform ( Fig. 1) to elongate, with rounded extremities ( Figs. 2–5). Rhynchus sucker­like with ventrally subterminal aperture and apical cap­like muscular hood present, most clearly seen in unflattened specimens. Mouth mid­ventral, pre­equatorial. Pharynx muscular, spherical, anterior to middle of body. Oesophagus tubular of variable length. Caecum saccular, oval, directed posteriorly to pharynx in holotype ( Fig. 1) or anteriorly to pharynx and recurved, in all other specimens ( Figs. 2–5). Testes two, subglobular, tandem or oblique, contiguous or separated by uterus. Anterior testis at about mid­body or just preequatorial, posterior testis just post­equatorial or further posterior. Cirrus­sac elongate, sinistral, submedian, with distal extremity close to posterior end of body and proximal extremity close to level of posterior testis or far from it; containing oval seminal vesicle and well­developed curved pars prostatica. Genital atrium thin­walled, elongated, with genital pore ventrally subterminal. Ovary oval, pretesticular, close to anterior testis ( Fig. 2), or separated from it by uterine loops ( Fig. 5), or separated by caeca ( Figs. 1, 3), or at level of anterior testis ( Fig. 4). Mehlis’ gland and saccular seminal receptacle postovarian. Laurer’s canal not seen. Vitelline follicles extending from level midway between pharynx and rhynchus to level of pharynx; fields fusing anteriorly to form an arch. Uterus from ovarian level to posterior extremity of body opening into genital atrium, may occasionally reach level of anterior vitelline follicles. Eggs numerous, operculate.