A new Centromochlus Kner, 1858 (Siluriformes: Auchenipteridae: Centromochlinae) from the transition between Amazon floodplain and Guiana shield, Brazil

ABSTRACT

Species of Centromochlus are widely distributed in South America, with records for major basins such as the Amazon and Orinoco, rivers draining the Guiana Shield such as the Essequibo, Courantyne (Corantijn), Coppename, Maroni, and Oyapock, and Brazilian Shield drainages as upper Paraná and São Francisco. In the last four years, three species of Centromochlus have been described, raising the total number of valid species to sixteen. The new species of Centromochlus described herein is diagnosed by having black ground color sharply delimited from a white underside by conspicuous wavy border. The new species is recorded from the Nhamundá, left bank tributary to the lower Amazon that drain from the Brazilian portion of the Guiana Shield. Although apparently similar to some Tatia species (e.g. Tatia musaica , T. carolae and T. melanoleuca ), the new species possess two conditions of the Weberian apparatus otherwise observed only in Centromochlus heckelii and C. existimatus among centromochlin catfishes. The new Centromochlus comprises small catfishes with adults ranging from 48 to 57 mm SL.

Keywords:
Doradoidea; Ostariophysi; South America; Systematics; Tatia .