Revision of the genus Pseudotocinclus (Siluriformes: Loricariidae: Hypoptopomatinae), with descriptions of two new species

Abstract

The genus Pseudotocinclus is revised and two new species are described: Pseudotocinclus juquiae from the Ribeira de Iguape basin and Pseudotocinclus parahybae from the rio Paraíba do Sul basin. The presence of a small naked area on the snout tip distinguishes P. tietensis from P. parahybae and P. juquiae, which have the snout tip covered with small platelets. In addition, P. tietensis has four transverse dark-brown bands on the dorsum coalesced with the midlateral stripe instead of three, as in its congeners. Pseudotocinclus juquiae is distinguished from its congeners by having the orbital ring very prominent and conspicuous, a characteristic not found in P. tietensis or P. parahybae. These three species also differ from their congeners by meristic and morphometric data. Comments on the past connection of Ribeira de Iguape, Paraíba do Sul and upper Tietê basins are presented.O gênero Pseudotocinclus é revisado e duas novas espécies são descritas: Pseudotocinclus juquiae da bacia do rio Ribeira de Iguape e Pseudotocinclus parahybae da bacia do rio Paraíba do Sul. A presença de uma pequena área nua na ponta do focinho distingue P. tietensis de P. parahybae e P. juquiae, que apresentam a ponta do focinho coberta por pequenas placas. Além disso, P. tietensis tem quatro bandas transversas marrom-escuras na região dorsal do corpo, fundidas com uma barra mediana lateral, ao invés de três bandas, como nas demais espécies. Pseudotocinclus juquiae distingue-se de suas congêneres pela presença de um anel orbital muito proeminente e conspícuo não observado em P. tietensis ou P. parahybae. As três espécies também diferem quanto a seus dados morfométricos e merísticos. São apresentados comentários a respeito das conexões pretéritas das bacias dos rios Ribeira de Iguape, alto Tietê e Paraíba do Sul.

Hidden diversity and evolutionary diversification in Phalloceros harpagos Lucinda (Cyprinodontiformes: Poeciliidae)

“…Several studies have demonstrated the distribution of fish species between these basins (Ribeiro, 2006;Takako et al, 2005). (Frota et al, 2019) and the Paranapanema River (Frota et al, 2020).…”

“…Several studies have demonstrated the distribution of fish species between these basins (Ribeiro, 2006; Takako et al, 2005). For example, Cambeva davisi (Haseman 1911) and Rhamdiopsis moreirai Haseman 1911 occur in the Iguaçu River (interior slope) and Ribeira de Iguape (Atlantic slope; Ingenito et al, 2004), Hypostomus ancistroides Iheringi 1911 in the Iguaçu River, Ribeira de Iguape River and Paranapanema (interior slope of the upper Paraná River; Oyakawa et al, 2005).…”

Astyanax lineatus (Perugia, 1891) (Characiformes: Characidae): first record in the upper Paraná river basin, Mato Grosso do Sul, Brazil

“…ter capture events between nearby basins (Lima & Ribeiro 2011). The occurrence of the dynamic process of headwater capture has been widely demonstrated by studies in the upper Paraná basin, mainly on its eastern border, and have shown that geomorphological processes can influence the dispersal of fish species within the system itself (Shibatta & Benine 2005;Takako et al 2005). Headwater capture can occur by tectonic movement or by erosion (Tarbuck & Lutgens 2002).…”

A new species of Pimelodus La Cépède, 1803 (Siluriformes: Pimelodidae) from rio Ribeira de Iguape basin, Brazil

“…In the last seven years, eight new fish species were described based on recent collection efforts in the rio Ribeira de Iguape basin (e.g., Pereira & Oyakawa, 2003;Costa et al, 2004;Oyakawa et al, 2005;Takako et al, 2005;Wosiacki & Oyakawa, 2005;Costa, 2006;Ottoni et al, 2008). The new species described here increases the number of known species of the interesting ichthyofauna of that drainage.…”