Description

SINGLE PAPER

Volume 20, Issue 2 – 15 April 2014

Dalton Tavares Bressane Nielsen, Mayler Martins and Ricardo Britzke: Description of a new species of annual fish, Maratecoara gesmonei (Cyprinodontiformes: Rivulidae) from the rio Xingu system, Amazon basin, Brazil, pp. 87-96

Abstract

Maratecoara gesmonei n. sp., found on a temporary pool at a fluvial island in the middle rio Xingu, Pará State, Brazil, is described herein. This is the first occurrence of this genus in the Rio Xingu drainage, Amazon basin. The new species differs from all congeners by its unique color pattern which lacks horizontal rows of small dark orange spots on the antero-dorsal portion of the flanks (vs. 2-3 on M. lacortei, 3 on M. formosa and M. splendida), or orange oblique bars on anteroventral portion of trunk (vs. 4-5 orange oblique bars on anteroventral portion of trunk in M. formosa, 3-4 in M. splendida or a broad blotch in M. lacortei). In addition, the new species can be diagnosed from congeners by its lower body depth (23.7-25.9% SL vs. 30.4-40.0% SL), lower caudal peduncle depth (13.0-15.5% SL vs. 17.1-21.6% SL), and lower number of vertebrae, 25-26 (vs. 27-28 in M. lacortei, 26-27 in M. formosa, and 27 in M. splendida).