REDESCRIPTION OF CYSTIDICOLOIDES FISCHERI BASED ON SPECIMENS FROM PIRANHAS IN BRAZIL, AND ERECTION O
June 27th, 2008 | by admin |REDESCRIPTION OF CYSTIDICOLOIDES FISCHERI BASED ON SPECIMENS FROM PIRANHAS IN BRAZIL, AND ERECTION OF A NEW GENUS (NEMATODA: CYSTIDICOLIDAE).
The cystidicolid nematode Cystidicoloides fischeri (Travassos, Artigas and Pereira, 1928) is redescribed from specimens collected from the stomach of the San Francisco piranha Pygocentrus piraya (Cuvier) and the white piranha Serrasalmus brandtii (Lutken) (both Characidae, Characiformes) (new host records) from the Tres Marias Reservoir, Upper Sao Francisco River, Minas Gerais State, Brazil. The morphology of this type species of Cystidicoloides Skinker, 1931, studied with both light and scanning electron microscopy, is characterized by some taxonomically important, previously unreported features, such as the presence of a cephalic cuticular collarette, subdorsal and subventral cephalic spikes, cuticular tooth-like elevations inside the prostom, deirids, area rugosa, and details in the structure of the cephalic end. Heliconema izecksohni Fabio, 1982 is transferred to Cystidicoloides as C. izecksohni (Fabio, 1982) n. comb. Cystidicoloides uniseriata Valovaya and Valter, 1988 is considered a species inquirenda with uncertain generic appurtenance. Mainly the presence of subdorsal and subventral cephalic spikes and of the collarette are characteristic of Cystidicoloides, comprising only species parasitizing Neotropical fishes. The species from salmonids in the Holarctic, hitherto reported mostly as Cystidicoloides ephemeridarum (Linstow, 1872), belongs to a different, newly erected genus, for which the name Salmonema Moravec n. gen. (type species S. ephemeridarum) is now proposed. Cystidicoloides prevosti (Choquette, 1951)is transferred to Salmonema as S. prevosti (Choquette, 1951) n. comb. Sterliadochona ssavini Skryabin, 1946 and Sterliadochona Skryabin, 1946 are considered a species inquirenda and a genus inquirendum, respectively. A key to species of Cystidicoloides is provided.
Moravec F, Santos M, Brasil-Sato M.