A new species of leaffish Polycentrus Müller & Troschel, 1849 (Percomorpha: Polycentridae) from the rio Negro, Brazil

Abstract

A new species of Polycentrus is described from the rio Negro, in Brazil. It is distinguished from P. schomburgkii by the presence of two dark postocular and one subocular band, all smaller than orbital diameter, blunt snout, isognathous mouth, reduction of the serrations on the lower edge of the lacrimal-spines ranging from zero to two tiny spines at the posterior end, intensely serrated edge of the interopercle, fully serrated posterior edge of the vertical arm of the preopercle, presence of five pungent opercular spines, subopercle broadly serrated along most of its posterior ventral edge, presence of serrations dorsally on the posterior margin of the cleithrum, fourth ray of pectoral fin reaching the vertical through the anal-fin origin, 19-21 predorsal scales, 19-20 scales on dorsal-fin base, 12-14 scales on anal-fin base, and absence of a median opercular blotch. Uma nova espécie de Polycentrus é descrita do rio Negro, Brasil. Distingue-se de P. schomburgkii por duas bandas postoculares escuras e uma banda subocular menores do que o diâmetro do olho, focinho pontudo, boca isognata, cinco espinhos operculares pungentes, borda posterior do braço vertical do pré-opérculo totalmente serrilhada, serrilhas ausente na borda inferior do lacrimal ou duas pequenas serrilhas na margem posterior, subopercular amplamente serrilhada ao longo da borda, cleitro com serrilhas na margem posterior do processo dorsal, interopercular com borda amplamente serrilhada, quarto raio da nadadeira peitoral atingindo a vertical de origem da nadadeira anal, 19-20 escamas na base da nadadeira dorsal, 12-14 escamas na base de nadadeira anal, 19-21 escamas pré-dorsais e ausência de mancha opercular.

Phylogenetic systematics of leaffishes (Teleostei: Polycentridae, Nandidae)

“…); the extreme of this specialization is found in Monocirrhus with its petiole‐mimicking chin barbel (Eigenmann and Allen ). Due to their disjunct distributions, relationships among the leaffishes have been of interest in the study of continental biogeography (Cracraft ; Lundberg ), but despite their low diversity – Afronandus , Polycentropsis and Monocirrhus are monotypic while Polycentrus and Nandus have two and six valid species respectively (Ng ; Coutinho and Wosiacki ) – their phylogenetic affiliations have been difficult to ascertain, due in part to their ostensibly convergent appearances. Consequently, the systematic history of the leaffishes was described by Berra () as ‘tortured’ (p. 425), with genera having been classified and reclassified in several families on multiple occasions (Table ).…”

Taxonomia E Filogenia De Peixes De Riachos Brasileiros

“…Esta espécie ocorre nos rios e igarapés costeiros das Guianas e planícies Amazônica e do Orinoco (Cardona & Osinaga 2006, Menezes & Buckup 2007. Polycentrus schomburgkii ocorre nos rios costeiros da Venezuela, Trinidad, Guianas e do Estado do Amapá no Brasil (Coutinho & Wosiacki 2014), sendo também registrada na região de Salvador e na planície costeira do Rio de Janeiro, até o rio da Guarda na Baixada Fluminense (Menezes & Buckup 2007).…”