A new nematode species, Guyanema longispiculum sp. n. is described from the abdominal cavity of the freshwater armoured catfish, Loricariichthys hrunneus (Hancock), from two localities in western Venezuela. It differs from all hitherto known members of the genus in having unusually long spicules (0.480-0.609 mm) and from individual species also by other morphological and biometrical features. It is characterized by the presence of eight cephalic papillae arranged in two circlets, localization of deirids anterior to the nerve ring, a conical, undivided tip of the tail in both sexes, four pairs of preanal and six pairs of postanal papillae in the male, and a markedly elevated vulva in the female. A key to species of Guyanema is presented.
Proteocephalus macrophallus (Diesing, 1850), considered by several authors as species inquireruia, was recently found in Cichla ocellaris in Venezuela. This material is compared with voucher specimens from the same host (C. ocellaris) from Brazil, identified and redescribed as P. macrophallus by Woodland (1933). The specific status of P. macrophallus is confirmed. This species is characterized by: 1 ) the shape of the body, which is wide and short, 2) the absence of a neck, 3) the distribution of the vitelline follicles, which converge posteriorly to the ovarian lobes, and 4) the structure of the uterus, which is evacuated in the last proglottides and transformed to thick-walled diverticles apparently separated each from other. A neotype is designated.
The present paper comprises a systematic survey of nematodes found in 88 specimens of 24 species of freshwater fishes in Venezuela in 1992 and 1994. The following 13 species of nematodes were recorded: Adults: Guyanema longispiculum Moravec, Prouza et Royero, 1996, Guyunema sp., Procamallanus (Spiracamallanus) inupinatus Travassos, Artigas et Pereira, 1928, P. (S.) krameri (Petter, 1974) comb, n., P. (S.) pintoi (Kohn et Fernandes, 1988) comb, n., Procamallanus (Spiracamallanus) sp., Ruphidascaris (Sprentascaris) mahnerti (Petter et Cassone, 1984). Larvae: Anisakidae gen. sp., Brevimullicaecum sp., Ctmtracaecum sp. Type 1, Contracaecum sp. Type 2, Contracaecum sp. Type 3, Eustrongylides sp. All these parasites are reported from Venezuela for the first time and all findings represent new host records. Brevimulticae-cum larvae are reported from fishes for the first time. Almost all parasites are briefly described and illustrated and problems concerning their morphology, taxonomy, hosts and geographical distribution are discussed. A new name, Terranova diazungriai nom. nov. is proposed for T. caballeroi Diaz-Ungrfa, 1968 (a junior homonym of T. caballeroi Baruš et Coy Otero, 1966).