A new species of the catfish Neoplecostomus (Loricariidae: Neoplecostominae) from a coastal drainage in southeastern Brazil

Abstract

A new species of loricariid catfish is described from the rio Perequê-Açú and surrounding basins, Parati, Rio de Janeiro State. The new species has the accessory process of ceratobranchial 1 more slender than the main body of the ceratobranchial, and a very large sesamoid ossification, markedly greater in size than the interhyal. Additionally, the new species presents a distinct dorsal color pattern consisting of a conspicuous horseshoe shaped light blotch with a central dark area posterior to the supraoccipital. Uma espécie nova de loricarídeo é descrita do rio Perequê-Açú e bacias circundantes, Parati, Rio de Janeiro. A espécie nova apresenta o processo acessório do ceratobranquial 1 mais delgado do que o corpo principal do ceratobranquial, e uma ossificação sesamoide muito grande, marcadamente maior em tamanho do que o interhial. Adicionalmente, a espécie nova apresenta um padrão de colorido dorsal distinto que consiste em uma conspícua mancha clara em forma de casco de cavalo com uma área escura no centro posterior ao supraoccipital.

Headwater Capture Evidenced by Paleo-Rivers Reconstruction and Population Genetic Structure of the Armored Catfish (Pareiorhaphis garbei) in the Serra do Mar Mountains of Southeastern Brazil

“…Pareiorhaphis garbei was the subject of a taxonomic review ( Pereira and Reis, 2002 ; Pereira, 2005 ) that did not include molecular data, preventing the discovery of deep genetic structure. Several other demersal Neotropical freshwater fishes that display only subtle morphological differences have proved to show substantial genetic divergences that support the description of new and often endemic species ( Benine et al, 2009 ; Melo et al, 2011 ; Cherobim et al, 2016 ), and some of these support an ancient split between rivers flowing to the Guanabara Bay versus the São João and Macaé drainages ( Villa-Verde et al, 2012 ; Costa, 2014 ; Roxo et al, 2017 ). All molecular analyses herein performed indicate high divergence of the KAE population of P. garbei from all others, strongly suggesting that individuals from these two groups represent different species.…”

“…Deforestation, chemical pesticides, and the introduction of rainbow trout Oncorhynchus mykiss (Walbaum, 1792) were shown to be threats for P. garbei ( Pereira and Brito, 2008 ), even though most records for the species are in protected areas ( Maia et al, 2013 ). However, molecular studies indicate that some taxa putatively distributed along coastal basins of the Fluminense ecoregion may be species complexes with individually narrow distributions ( Villa-Verde et al, 2012 ; Cherobim et al, 2016 ; Roxo et al, 2017 ).…”

Species delimitation in a range‐restricted group of cascudinhos (Loricariidae: Epactionotus) supports morphological and genetic differentiation across coastal rivers of southern Brazil

“…Indeed, genetic divergence is frequently observed between populations of Neotropical freshwater fishes in isolated drainages (Hirschmann et al ., 2015; Lima et al ., 2017; Thomaz et al ., 2015). Nonetheless, this divergence is not often accompanied or supported by morphological differences (Benine et al ., 2009; Cherobim et al ., 2016; Lima et al ., 2017; Melo et al ., 2011), especially in this relatively small geographic scale (Hirschmann et al ., 2015), which contrasts with the analyses in Epactionotus that show some morphometric variation among groups (Figures 11 and 12). The morphological features that most strongly distinguish the drainage populations observed here ( e.g ., body shape and dermal plates) can also be associated with adaptations to habitat types and locomotion (Carvalho & Reis, 2011; Fagundes et al ., 2020; Roxo et al ., 2017).…”

Composition and distribution of fishes from the Perequê-Açu river basin, Paraty, Rio de Janeiro, Southeastern Brazil

“…In this way, PERMANOVA, PCoA, and SIMPER results indicate that the composition of the fishes along the catchment is not homogenous. In the upper reaches of the basin, the substrate of rocks, fast-flowing water in rapids areas, and moderate riparian vegetation seem to be favorable to the greater abundances of Loricariidae species such as Neoplecostomus paraty, strongly associated with these environments (Cherobim et al 2016). On the other hand, these slope headwater habitats limit the great majority of species, mainly Characiformes and Cyprinodontiformes.…”