A new species of Hyphessobrycon Durbin (Characiformes: Characidae) from rio Aripuanã, rio Madeira basin, Brazil

Abstract

A new species of Hyphessobrycon is described from the rio Aripuanã, rio Madeira basin, Amazonas State, Brazil. Hyphessobrycon procyon can be distinguished from its congeners by the unique combination of the following features: elongation of the dorsal fin in mature males, absence of dark blotches on the dorsal fin, and presence of two humeral blotches. The possibility of a relationship of the new species within H. elachys, H. heliacus, H. loweae, H. moniliger, and H. peugeoti is discussed based on the sharing of characteristics related to the sexual dimorphism and tooth morphology.

Fishes from the Jaru Biological Reserve, Machado River drainage, Madeira River basin, Rondônia State, northern Brazil

“…The current work contributed 24 species to the general inventory of the Machado River and 26 species to the inventory conducted in Conservation Units in the Rondônia State. Additionally, the material deposited in the Brazilian collections enabled the accomplishment of recent taxonomic studies, which contributed to enhancing the knowledge of the ichthyofauna of both the Madeira River (Rocha et al 2008a, Rocha et al 2008b, Zanata & Ohara 2009, Ribeiro et al 2011, Ohara 2012, Marinho & Ohara 2013, Zanata & Ohara 2015, Ohara & Lima 2015a, Tencatt & Ohara 2016a, Ohara & Neuhaus 2016, Pastana & Ohara 2016, and the Machado River (Ohara & Lima 2015b, Ohara & Marinho 2016.…”

A new sexually dichromatic miniature Hyphessobrycon (Teleostei: Characiformes: Characidae) from the Rio Formiga, upper Rio Juruena basin, Mato Grosso, Brazil, with a review of sexual dichromatism in Characiformes

“…(a), (b)]. Secondary sexual dimorphism is frequently reported and discussed among characiforms, mainly regarding the presence of bony hooks on fins (Wiley & Collette, ; Fink & Weitzman, ; Weitzman & Fink, ; Weitzman et al ., ; Malabarba & Weitzman, , , ; Lima & Sousa, ; Camelier & Zanata, ; Vieira et al ., ) or shape of the dorsal and anal fins (Costa & Géry, ; Weitzman & Palmer, ; Moreira et al ., , b ; Teixeira et al ., ; Ingenito et al ., ; Dagosta et al ., ; Marinho et al ., ; Pastana & Ohara, ). Although sexual dichromatism in Characidae has been known for over a century (Eigenmann, , ), descriptions of such dimorphism are still scarce in taxonomic literature.…”

Hyphessobrycon platyodus (Teleostei: Characiformes), a new species from the Rio Madeira basin, Brazil, with comments on how multicuspid teeth relate to feeding habits in Characidae

“…Hyphessobrycon platyodus shares some features with the species of Hyphessobrycon loweae ‐group ( sensu Ingenito et al ., ; Pastana & Ohara, ), which include elongated dorsal fin in adult males, absence of bony hooks on the fin rays and a straight profile of the distal margin of the anal fin. Pastana & Ohara () mentioned that, although tooth cusps are highly variable among Neotropical tetras, multiple tooth cusps (with several or more cusps) are an additional shared character for the Hyphessobrycon loweae ‐group. Additionally, the species assigned to the H. loweae ‐group exhibit sexually dimorphic live colouration (except, H. moniliger Moreira, Lima & Costa 2002).…”

“…There are currently 12 species of Hyphessobrycon listed from the Brazilian portion of Rio Madeira basin (Lima et al ., ). This number continues to increase, however, as new species are regularly described (Ohara & Lima, ; Pastana & Ohara, ; Ohara et al ., ). Furthermore, recent fieldwork in the middle portions of the Rio Madeira basin in Amazonas State has yielded additional undescribed species that fit the current definition of Hyphessobrycon , suggesting that the real diversity of Hyphessobrycon in the Brazilian portion of Rio Madeira basin is far from completely described.…”

“…Hyphessobrycon Durbin 1908 is one of the most species-rich genera of small characid fishes, comprising 143 species currently considered valid (Ohara & Lima, 2015;Teixeira et al, 2016;Lima & Flausino, 2016;Pastana & Ohara, 2016). Species of the genus are widely distributed from southern México to the Río de La Plata in Argentina (Lima et al, 2003), with its highest species richness occurring in the Amazon Basin (Ohara & Lima, 2015).…”