Abstract
A new species of Neotropical electric fish, Gymnotus ucamara, is described from floodplain habitats in the Rio Ucayali Basin, Peru. The new species is distinguishable from all congeners by the following combination of characters: a clear patch at the caudal end of the anal fin; two laterosensory canal pores (from the preopercular-mandibular series) in the dorso-posterior portion of the preopercle; a coloration pattern with 18–24 dark brown bands separated by narrow pale interbands which are less than one-third the width of the dark bands; a long head (12.2–13.4 % total length); many (10–11) scales rows over the anal fin pterygiophores; few (38-43) pored lateral-line scales to the first lateral-line ramus; and a low (75–91) total number of pored lateral-line scales.
References
Albert, J. S. (2001) Species diversity and phylogenetic systematics of American knifefishes (Gymnotiformes, Teleostei). Miscellaneous Publications of the Museum of Zoology, University of Michigan, 190, 1–127.
Albert, J. S. & Crampton, W. G. R. (2001) Five new species of Gymnotus (Teleostei: Gymnotiformes) from an Upper Amazonian floodplain, with descriptions of electric organ discharges and ecology. Ichthyological Exploration of Freshwaters, 12 (3), 241–266.
Albert, J. S., Fernandes-Matioli, F. M. de. & Almeida-Toledo, L. F. (1999) New species of Gymnotus (Gymnotiformes, Teleostei) from Southeastern Brazil: towards the deconstruction of Gymnotus carapo. Copeia, 1999 (2), 410–421.
Albert, J. S. & Miller, R. R. (1995) Gymnotus maculosus, a new species of electric fish (Chordata: Teleostei: Gymnotoidei) from Middle America, with a key to species of Gymnotus. Proceedings of the Biological Society of Washington, 108 (4), 662–678.
Ayres, J. M. (1993) As matas de várzea do Mamirauá: Medio Rio Solimões, MCT-CNPq, Brasilia, 123 pp.
Campos da Paz, R. (1996) Redescription of the Central American electric fish Gymnotus cylindricus (Ostariophysi: Gymnotiformes: Gymnotidae), with comments on character ambiguity within the ostariophysan clade. Journal of Zoology, London, 240, 371–382.
Campos da Paz, R. (2000) Taxonomic status of Rhamphichthys cingulatus Brind and a more precise assignment of the type-locality of Gymnotus coatesi LaMonte (Ostariophysi: Gymnotiformes). Copeia, 2000 (4), 1114–1117.
Campos da Paz, R. (2002) Gymnotus diamantinensis, a new species of electric knifefish from Upper Rio Arinos basin, Brazil (Ostariophysi: Gymnotidae). Ichthyological Exploration of Freshwaters, 13 (2), 185–192.
Campos da Paz, R. & Costa, W. J. E. M. (1996) Gymnotus bahianus sp. nov., a new gymnotid fish from Eastern Brazil (Teleostei: Ostariophysi: Gymnotiformes), with evidence for the monophyly of the genus. Copeia, 1996 (4), 937–944.
Crampton, W. G. R. (1996) Gymnotiform fish: an important component of Amazonian flood plain fish communities. Journal of Fish Biology, 48, 298–301.
Crampton, W. G. R. (1998) Electric signal design and habitat preferences in a species rich assemblage of gymnotiform fishes from the Upper Amazon basin. Annais da Academia Brasileira de Ciências, 70 (4), 805–847.
Dingerkus, G. & Uhler, L. D. (1977) Enzyme clearing of alcian blue stained whole small vertebrates for demonstration of cartilage. Stain Technology, 52 (4), 229–232.
Junk, W. J., Ed. (1997) The Central Amazon floodplain: Ecology of a Pulsing System, Springer, Berlin, 525 pp.
Leviton, A. E., Gibbs, R. H., Heal, E. & Dawson, C. E. (1985) Standards in herpetology and ichthyology: Part I. Standard symbolic codes for institutional resource collections in herpetology and ichthyology. Copeia, 1985, 802–832.
Mago-Leccia, F. (1994) Electric Fishes of the Continental Waters of America, Clemente, Caracas, 206 pp.