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| Cambeva gamabelardense Costa, Feltrin & Katz, 2022 |
Numerous species in fast–flowing streams of southern Brazil have not been described to date. As some of these species inhabit areas under pressure due to the ongoing, intense process of environmental degradation, formal descriptions are urgently needed so as to elaborate strategies for their conservation. We describe a new species, Cambeva gamabelardense n. sp., found in the middle Rio Chapecó drainage, Uruguay River basin, in an area where intense deforestation and soya plantation is endangering fish species. The new species is considered closely related to C. panthera, a species occurring in an isolated coastal basin about 380 km from the area inhabited by the new species, as the two species share a unique jaguar–like pattern on the flank. The new species differs from C. panthera by having shorter barbels, a different position of the origin of the dorsal–fin, more vertebrae, and osteological features that are unique among congeners.
Keywords: Cambeva gamabelardense n. sp., Comparative morphology, Mountain biodiversity, Osteology, Uruguay River basin
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| Cambeva gamabelardense n. sp., holotype, UFRJ 7003, 107.2 mm SL: A, lateral view; B, dorsal view; C, ventral view. |
Class Actinopterygii Klein, 1885
Order Siluriformes Cuvier, 1817
Family Trichomycteridae Bleeker, 1858
Cambeva gamabelardense n. sp. (figs. 1–2)
Diagnosis: Cambeva gamabelardense is distinguished from all other congeners, except C. panthera Costa, Feltrin and Katz, 2021, by having a jaguar–like colour pattern on the flank, consisting of irregularly shaped pale brown spots of variable size and shape, with their margins overlapped by small dark brown spots (fig. 1; vs. never a similar colour pattern). Cambeva gamabelardense differs from C. panthera by having shorter barbels, with the tip of the maxillary and rictal barbels reaching the middle portion of the interopercular patch of odontodes (vs. the tip of the maxillary barbel reaching the middle of the pectoral–fin base and the tip of the rictal barbel reaching between the interopercular patch of odontodes and the pectoral–fin base) and the tip of the nasal barbel reaching between the eye and the opercular patch of odontodes (vs. the tip of the nasal barbel reaching the middle of opercular patch of odontodes); the first pectoral–fin ray terminating in a rudimentary filament, weakly extending beyond the fin membrane (vs. filament about 10–15% of the pectoral–fin length); the posterior extremity of the pelvic fin at a vertical through the anterior portion of the dorsal–fin base (vs. middle portion); the dorsal–fin origin at a vertical through the centrum of the 20th or 21st vertebra (vs. through the centrum of the 18th or 19th vertebra); and 38 or 39 vertebrae (vs. 37). Cambeva gamabelardense differs from all other trichomycterines examined by its long metapterygoid, its horizontal length longer than the horizontal length of hyomandibula anterior outgrowth (fig. 2B; vs. shorter) and a small lateral projection on the lateral margin of the lateral ethmoid, just posterior to the articular facet for the autopalatine (fig. 2A; vs. absence of a similar projection).
Distribution: Cambeva gamabelardense n. sp. is only known from the type locality area, in the upper Rio Chapecó drainage, Rio Uruguai basin, at altitudes between about 750 and 860 m a.s.l. (fig. 3).
Etymology: The name gamabelardense (gamma, the third letter of the Greek alphabet, and abelardense, a Portuguese word referring to people born in Abelardo Luz municipality) is an allusion to the third new species of Cambeva known to occur in this area. The other two species are described in Costa et al. (2022).
W. J. M. Costa, C. R. M. Feltrin and A. M. Katz. 2022. An Endangered New Catfish Species of the Genus Cambeva (Cambeva gamabelardense n. sp.) (Siluriformes, Trichomycteridae) from the Rio Chapecó drainage, southern Brazil. Animal Biodiversity and Conservation. 45.1: 123-129. DOI: 10.32800/abc.2022.45.0123
