Three new species of the Eigenmannia trilineata species group (Gymnotiformes: Sternopygidae) from northwestern South America

Abstract

Eigenmannia is one of the more taxonomically complex genera within the Gymnotiformes. Here we adopt an integrative taxonomic approach, combining osteology, COI gene sequences, and geometric morphometrics to describe three new species belonging to the E. trilineata species group from Colombian trans-Andean region. These new species increase the number of species in the E. trilineata complex to 18 and the number of species in the genus to 25. The distribution range of the E. trilineata species group is expanded to include parts of northwestern South America and southern Central America.

Morphology‐based phylogeny of Eigenmanniinae Mago‐Leccia, 1978 (Teleostei: Gymnotiformes: Sternopygidae), with a new classification

“…besouro Peixoto & Wosiacki, 2016, E . camposi Herrera‐Collazos et al, 2020, E . correntes Campos‐da‐Paz & Queiroz, 2017, E .…”

“…macrops (Boulenger, 1897), E . magoi Herrera‐Collazos et al, 2020, E . matintapereira Peixoto et al, 2015, E. meeki Dutra et al, 2017, E .…”

New species of glass knifefish genus Eigenmannia (Gymnotiformes: Sternopygidae) with comments on the morphology and function of the enlarged cephalic lateral‐line canals of Sternopygidae

“…These canals exhibit a mosaic of narrow and widened canals (Albert, 2001; Mago‐Leccia, 1978; Tagliacollo et al ., 2016) in a morphology so far registered to few fishes of unrelated taxa, such as Cyprinidae (Reno, 1971), Gasteropelecidae (Pastana et al ., 2020) and Pleuronectidae (Sakamoto, 1984). Among sternopygids, Eigenmannia Jordan and Evermann 1896 is currently the most species‐rich genus, comprising 26 valid species, with at least half of its diversity described in the past decade (Fricke et al ., 2020; Herrera‐Collazos et al ., 2020; Peixoto & Ohara, 2019). Species of the genus are distributed along Central and South America, ranging from the Rio Tuíra basin in Panamá to the Rio de La Plata basin in Argentina (Peixoto et al ., 2015), with its greatest species diversity found in the Amazon basin, where approximately half of the known species are found (Peixoto & Ohara, 2019).…”

“…Despite several recent taxonomic contributions (Campos‐da‐Paz & Queiroz, 2017; Dutra et al ., 2017, 2018; Herrera‐Collazos et al ., 2020; Peixoto et al ., 2015; Peixoto & Ohara, 2019; Peixoto & Waltz, 2017; Peixoto & Wosiacki, 2016; Waltz & Albert, 2018), the monophyly of Eigenmannia still awaits further phylogenetic studies, and currently its infrageneric classification is based on informal groups of species (see discussion in Peixoto & Ohara, 2019: Table 2). Among these, the Eigenmannia trilineata species group allocates the highest number of species and encompasses taxa that exhibit a midlateral stripe between the LL and the proximal portion of the pterygiophores of the anal fin, named the ‘superior midlateral stripe’ (Peixoto et al ., 2015; Peixoto & Wosiacki, 2016).…”

“…Among these, the Eigenmannia trilineata species group allocates the highest number of species and encompasses taxa that exhibit a midlateral stripe between the LL and the proximal portion of the pterygiophores of the anal fin, named the ‘superior midlateral stripe’ (Peixoto et al ., 2015; Peixoto & Wosiacki, 2016). Currently, the group is composed of 18 species, 15 of these being described within the past 10 years ( e.g ., Herrera‐Collazos et al ., 2020; Peixoto et al ., 2015). The recent identification of gymnotiform specimens from the Rio Paraná basin yielded an additional and distinctive species that is allocated into the E. trilineata species group.…”