Two new species of Microglanis (Siluriformes: Pseudopimelodidae) from the upper-middle rio araguaia basin, Central Brazil

Abstract

Two new species of Microglanis are described from tributaries of upper-middle rio Araguaia, States of Mato Grosso and Goiás, Brazil. Microglanis oliveirai differs from its congeners by the short supraoccipital process not reaching the small anterior nuchal plate, and reduced number of gill rakers, lateral line pores, ribs, vertebrae, and caudal-fin rays. Microglanis xylographicus differs from its congeners by the presence of melanophores surrounding the neuromasts of the superficial lines, snout length 11.4-12.9% SL and body color pattern consisting of horizontal brown stripes similar to a wooden bark pattern. An identification key of Microglanis species from the Amazon basin is presented. © 2011 Sociedade Brasileira de Ictiologia.