Taxonomic study of Hoplias microlepis (Günther, 1864), a trans-Andean species of trahiras (Ostariophysi: Characiformes: Erythrinidae)

Abstract

The Hoplias malabaricus species group represents one of the most complexes taxonomical problems in the systematics of Neotropical fishes, including specimens widely distributed in most drainages of South America and part of Central America with great variation or overlap of putative diagnostic characters. The large number of nominal species, many of which without known type material, renders the problem more complicated. Currently, at least three nominal species can be included in the Hoplias malabaricus species group based on the form of the medial margins of dentaries and presence of tooth plates on the tongue: Hoplias malabaricus, H. teres, and H. microlepis, the latter representing the only exclusively trans-Andean known species of the genus. We present herein a taxonomic study of Hoplias microlepis based on examination of syntypes and recently collected specimens, including a redescription of the species. Hoplias microlepis occurs in the Pacific drainages of Panama and Southwestern Costa Rica, in addition to the río Guayas basin in Ecuador and the region near its mouth (río Tumbes, Northwestern Peru). Records of the species on the Atlantic coast of Panama are restricted to the Canal Zone, suggesting dispersal through the Panama Canal. We also designate lectotype and paralectotypes.O grupo de espécies Hoplias malabaricus representa um dos problemas taxonômicos mais complexos na sistemática de peixes Neotropicais, com ampla distribuição em quase todas as bacias da América do Sul e parte da América Central e grande variação ou sobreposição de prováveis caracteres diagnósticos. O grande número de espécies nominais, muitas delas sem material-tipo conhecido, é um fator complicador nessa questão. Atualmente, pelo menos três espécies nominais podem ser incluídas no grupo de espécies Hoplias malabaricus, com base no formato das margens mediais dos dentários e presença de dentes na língua: Hoplias malabaricus, H. teres e H. microlepis, a última sendo a única espécie exclusivamente trans-andina do gênero conhecida até o momento. Apresentamos aqui um estudo taxonômico de Hoplias microlepis, com exame dos síntipos e exemplares coletados mais recentemente, incluindo uma redescrição da espécie. Hoplias microlepis distribui-se nas bacias da costa Pacífica do Panamá e sudoeste da Costa Rica, além da bacia do río Guayas no Equador e região próxima à sua foz (río Tumbes, noroeste do Peru). Registros da espécie na costa Atlântica do Panamá são restritos à Zona do Canal, sugerindo dispersão através do Canal do Panamá. São designados também lectótipo e paralectótipos.

Comparative phylogeography of trans‐Andean freshwater fishes based on genome‐wide nuclear and mitochondrial markers

“…All analyses suggest that Hoplias malabaricus is a species complex containing two well‐structured lineages that, despite being morphologically indistinguishable, co‐occur at the same locations in the Catatumbo and Ranchería rivers without much gene exchange. Hoplias malabaricus is a widespread complex distributed in most drainages of South America (Mattox, Bifi, & Oyakawa, ; Rosso et al, ) that may in fact include many different species throughout its range. Cytogenetic studies have also reported sympatric lineages of H. malabaricus in the Doce River in Brazil and in the Ctalamochita River in Argentina with co‐occurring individuals having different karyotypes (Born & Bertollo, ; Grassi, Swarça, Dergam, Pastori, & Fenocchio, ; Jacobina, Paiva, & Dergam, ).…”

“…Cytogenetic studies have also reported sympatric lineages of H. malabaricus in the Doce River in Brazil and in the Ctalamochita River in Argentina with co‐occurring individuals having different karyotypes (Born & Bertollo, ; Grassi, Swarça, Dergam, Pastori, & Fenocchio, ; Jacobina, Paiva, & Dergam, ). Hoplias microlepis (formerly H. malabaricus ) has been recently described from the Pacific drainages of Panamá and Southwestern Costa Rica based on examination of syntypes and other specimens (Mattox et al, ). Ultimately, our results highlight the need of a comprehensive phylogeographic analysis of the H. malabaricus species complex based on material collected throughout its distributional range as well as an in‐depth taxonomic revision, including the description of many potential new species.…”

“…Cytogenetic studies have also reported sympatric lineages of H. malabaricus in the Doce River in Brazil and in the Ctalamochita River in Argentina with co-occurring individuals having different karyotypes (Born & Bertollo, 2006;Grassi, Swarça, Dergam, Pastori, & Fenocchio, 2017;Jacobina, Paiva, & Dergam, 2011). Hoplias microlepis (formerly H. malabaricus) has been recently described from the Pacific drainages of Panamá and Southwestern Costa Rica based on examination of syntypes and other specimens (Mattox et al, 2014).…”

“…Hoplias malabaricus is a widespread complex distributed in most drainages of South America (Mattox, Bifi, & Oyakawa, 2014;Rosso et al, 2018) that may in fact include many different species throughout its range. Cytogenetic studies have also reported sympatric lineages of H. malabaricus in the Doce River in Brazil and in the Ctalamochita River in Argentina with co-occurring individuals having different karyotypes (Born & Bertollo, 2006;Grassi, Swarça, Dergam, Pastori, & Fenocchio, 2017;Jacobina, Paiva, & Dergam, 2011).…”

Basin‐scale distribution and haplotype partitioning in different genetic lineages of the Neotropical migratory fish Salminus brasiliensis

“…Recently, cryptic diversity doubling the original number of valid species was detected within the genus Curimatopsis (Melo, Ochoa, Vari, & Oliveira, ). The Hoplias malabaricus species complex has been receiving particular attention during recent years (Mattox, Bifi, & Oyakawa, ) and two new species (Azpelicueta, Benítez, Aichino, & Mendez, ; Rosso et al, ) have been formally described recently. Cryptic diversity in the freshwater pufferfish genus Colomesus (Amaral, Brito, Silva, & Carvalho, ), and in pencilfishes of the genus Nannostomus (Benzaquem, Oliveira, da Silva Batista, Zuanon, & Porto, ) have also been revealed.…”