Proteocephalidae and Monticelliidae (Eucestoda : Proteocephalidea) parasites of freshwater fishes in Paraguay, with descriptions of a new genus and ten new species.

The present study treates 59 Proteocephalidean species, mostly based on rec ently collected material, distributed in 17 genera. Twenty one type species are revised. One new genus and 10 new species are described: Proteocephalu s mahnerti n. sp. parasite of Hoplerythrinus unitaeniatus; P. hobergi n. sp . of Oxydoras kneri; P. vladimirae n. sp. of Pinirampus pirinampu; P. pilar ensis n. sp. of Paraloricaria sp.; Monticellia dlouhyi n. sp. Acestrorhynch us altus; M. ventrei n. sp. of Pinirampus pirinampu; Ageneiella brevifilis n. gen., n. sp. of Ageneiosus brevifilis; Endorchis auchenipteri n. sp. of Auchenipterus osteomystax; Nupelia tomasi n. sp. of Trachelyopterus sp.; Ma riauxiella piscatorum n. sp. of Hemisorubim platyrhynchos. The following species are revised, many compared with the respective type m aterial: Proteocephalus rhamdiae Spector & Garzon, 1988; P. serrasalmus Reg o & Pavanelli, 1990; Choanoscolex abscisus (Riggenbach, 1896); Goezeella si luri Fuhrmann, 1916; Goezeella paranensis Pavanelli & Rego, 1989; Jauella g landicephala Rego & Pavanelli, 1985; Monticellia belavistensis Pavanelli et al., 1994; Monticellia coryphicephala (Monticelli, 1891); Monticellia magn a (Rego, dos Santos & Silva, 1974); Paramonticellia itaipuensis Pavanelli & Rego, 1991; Spatulifer maringaensis Pavanelli & Rego, 1989; Spatulifer cf. maringaensis Pavanelli & Reo, 1989; Monticellia spinulifera Woodland, 1935 ; Gibsoniela mandube (Woodland, 1935) Rego, 1984 (Syn. Anthobothrium mandub e); Harriscolex kaparari Rego, 1987; Nomimoscolex chubbi (Pavanelli & Takem oto, 1995); N. lopesi Rego, 1989; N. microacetabula Gil de Pertierra, 1995; Travassiella avitellina Rego & Pavanelli, 1987; Nupelia portoriquensis Pav anefli & Rego, 1991; Peltidocotyle rugosa Diesing, 1850. Following taxonomical actions are introduced: Spasskyellina Freze, 1965 syn , nov, of Monticellia; Monticellia mandi (Pavanelli & Takemoto, 1996) comb. nov, for Spasskyellina mandi Pavanelli & Takemoto, 1996; Gibsoniela meursa ulti nom. nov. for Endorchis mandube Woodland, 1935; Goezeella nupeliensis Pavanelli & Rego, 1991 syn, nov. of Paramonticellia itaipuensis Pavanelli & Rego, 1991. Monticellia loyolai Rego & Pavanelli 1992 syn. nov. of Montice llia magna (Rego, dos Santos & Silva, 1974). A lectotype is designated for Nomimoscolex admonticellia (Woodland, 1934). The genus Travassiella Rego & Pavanelli, 1987 is tranferred to Zygo bothriinae. Biloculate suckers are ob served in Othinoscolex lenha Woodland, 1933, originally described without s uckers. Mean prevalence is relatively high within the Monticelliidae (48%) and within the Proteocephalidae (30%). Most studied Proteocephalidea exhibi t oloxene type of specificity.