Two new species of Characidium Reinhardt (Characiformes: Crenuchidae) from northeastern Brazilian coastal drainages

Abstract

Two new species of Characidium, one from the rio Pardo basin, and another from the rio Paraguaçu basin, Bahia, Brazil, are described. The first new species is distinguished from its congeners by having conspicuous black vertical traces on body, formed by the concentration of melanophores along posterior margin of scales. The species further differs from most congeners by the presence of a conspicuous 3-shaped black blotch on the caudal fin and isthmus not covered by scales. The other new species is distinguished from congeners by having irregular dark blotches on dorsum alternating elongation to one or the other side of body, usually not connected to lateral blotches. The species can be further characterized by the absence of conspicuous blotches or bars on fins and the presence of secondary sexual dimorphism, such as pelvic fins of mature males longer than in females and with bony hooks. Duas novas espécies de Characidium, uma da bacia do rio Pardo e outra da bacia do rio Paraguaçu, Bahia, Brasil, são descritas. A primeira espécie nova distingue-se das congêneres por ter traços verticais pretos e conspícuos nas laterais do corpo, formados pela concentração de melanóforos ao longo da margem posterior das escamas. A espécie difere ainda da maioria das congêneres pela presença de faixa preta conspícua em forma de 3 na nadadeira caudal e istmo não coberto por escamas. A outra espécie nova se distingue das congêneres por ter manchas dorsais irregulares alternando alongamento para um ou outro lado do corpo, a maioria não conectada às manchas laterais. A espécie pode ser ainda caracterizada pela ausência de manchas ou barras conspícuas nas nadadeiras e pela presença de dimorfismo sexual secundário, tais como nadadeiras pélvicas dos machos maduros mais longas que em fêmeas e com espinhos ósseos.

A new species of Characidium Reinhardt, 1867 (Characiformes: Crenuchidae) endemic to the Atlantic Forest in Paraná State, southern Brazil

“…The reduction or absence of postcleithrum 1 (character 23, Buckup, 1993b) is only present in C. lauroi, C. oiticicai and C. schubarti, and the reduction of the fontanel and exclusion of the frontals from its anterior margin (character 8, Buckup, 1993b) is present in C. oiticicai and C. schubarti. These variations reinforce the need for further phylogenetic studies focused on the species of Characidium, with the inclusion of a larger number of species and new characters (Buckup, 1993b;Netto-Ferreira et al, 2013;Zanata & Camelier, 2015 …”

“…gomesi, and C. purpuratum. Later, the following five species were hy pothesized as members of clade C1, C. alipioi, C. amaila, C. japuhybense, C. kamakan, and C. timbuiense (Travassos, 1946(Travassos, , 1955bBuckup & Reis, 1997;Lujan et al, 2013;Zanata & Camelier, 2015). Five additional species of Characidium also have unscaled isthmus and are putative members of Clade C1: C. grajahuense, C. helmeri, C. macrolepidotus Peters, 1868, C. pterostictum, and C. vidali (Travassos, 1944(Travassos, , 1967Gomes, 1947;.…”

A new species of Characidium (Characiformes: Crenuchidae) from coastal basins in the Atlantic Rainforest of eastern Brazil, with phylogenetic and phylogeographic insights into the Characidium alipioi species group

“…cricarense, C. kamakan, and C. hasemani. Characidium alipioi, C. cricarense and C. kamakan are distributed in Atlantic rainforest coastal streams between the Pardo drainage in Bahia and the São João drainage in Rio de Janeiro (Leitão, Buckup, 2014;Zanata, Camelier, 2015). These species are morphologically similar, and have similar pigmentation patterns, including a B-shaped set of caudal bands, and the clearer area in front of the main dark band of dorsal fin.…”

“…Here we describe a new species of Characidium from the Northeastern Mata Atlântica Ecorregion in Eastern Brazil (Abell et al, 2008). Seven species of Characidium were previously reported from this area: Characidium bahiense Almeida, 1971, Characidium clistenesi Melo, Espíndola, 2016, Characidium deludens Zanata, Camelier, 2015, Characidium helmeri Zanata, Sarmento-Soares, Martins-Pinheiro, 2015, Characidium kamakan Zanata, Camelier, 2015, Characidium samurai Zanata, Camelier, 2014, and Characidium timbuiense Travassos, 1946. The fish species diversity of this Ecoregion is still poorly known, as suggested by the fact that five of these species of Characidium were described in the last three years.…”

New remarkable sexually dimorphic miniature species of Hyphessobrycon (Characiformes: Characidae) from the upper Rio Tapajós basin

“…According to Rapp Py‐Daniel & Fernandes (), fishes are particularly interesting and informative organisms in studies of sexual dimorphism due to many specializations found between the sexes. Characiformes is one of the largest components of the freshwater fish fauna world‐wide, spanning numerous examples of sexual dimorphism (Weitzman & Cobb, ; Vari, ; Weitzman & Palmer, ; Zanata & Vari, ; Menezes & Weitzman, ; Gama, ; Malabarba & Jerep, ; Zanata & Camelier, ; Ota et al, ). Such cases are particularly profuse in Characidae, the most diverse family of the order (Mirande, ; Oliveira et al, ).…”