Abstract
The current distribution of freshwater fishes across multiple basins along Eastern Brazil can be associated to two main events: river captures or temporary paleoconnections. Apparently, river captures had a more significant role on distribution and structuring of species from upland areas, such as Glandulocauda melanopleura. Populations of this species are found in contiguous drainages in presently isolated upper parts of Rio Tietê and the coastal basins of Guaratuba, Itatinga, Itanháem, and Ribeira de Iguape, in the Atlantic Forest domain. The allopatric and disjoint distribution of G. melanopleura associated with variation of morphological characters detected among geographically isolated populations stimulated this study. Thus, an integrative approach was undertaken, including morphological and molecular data, to better understand the evolutionary history of the species and the area where it occurs. Molecular analyses based on two mitochondrial markers revealed a strong genetic structure within G. melanopleura, that allowed recognition of two lineages, one distributed in both the upper Tietê and Itanhaém and the other in the Guaratuba. Overall, morphological data revealed some intraspecific overlapping variation, indicating that all samples are conspecific. Phylogenetic and phylogeographic analyses allied to divergence times and geomorphological information indicate that the current distribution of G. melanopleura is a result of relatively recent river captures involving the Tietê and some other coastal drainages. Although of recent origin, they occurred long enough to completely isolate these populations, since there are no haplotypes sharing between them. The conservation status of this species is also discussed, and our results corroborate the need to understand population structure for conservation planning.
Highlights
The tribe Glandulocaudini includes the genera Lophiobrycon, Glandulocauda, and Mimagoniates [1,2], represented by 10 small species, distributed in freshwater habitats of eastern and southern Brazil, Paraguay, and northeastern Uruguay [1,3]
All specimens used were collected in accordance with Brazilian laws, and the sampling was approved by the Instituto Chico Mendes de Conservacão da Biodiversidade (ICMBio) and Sistema de Autorizacão e Informacão em Biodiversidade (SISBIO) under a license issued in the name of Dr Osvaldo Oyakawa, research specialist of the fish section of the Museu de Zoologia da Universidade de São Paulo, where this study was carried out (SISBIO number 21924–1)
G. melanopleura is recovered as monophyletic (S1 Fig), including two clearly distinguished and strongly supported clades (Fig 1): one is represented by specimens from Rio Guaratuba basin (GUA) that is the sister group of the clade formed by specimens from upper Tietê (UPT) and Itanhaem (ITA) river basins
Summary
The tribe Glandulocaudini (former Glandulocaudinae of Menezes & Weitzman [1]) includes the genera Lophiobrycon, Glandulocauda, and Mimagoniates [1,2], represented by 10 small species, distributed in freshwater habitats of eastern and southern Brazil, Paraguay, and northeastern Uruguay [1,3]. Glandulocauda inequalis was placed in Mimagoniates [10,11] and, more recently, Menezes and Weitzman [1], in reviewing the systematics of the Glandulocaudini (at the time Glandulocaudinae), considered G. melanogenys a junior synonym of Hyphessobrycon melanopleurus Ellis ([12]: 157–158), which led these authors to propose the replacement of the species name melanogenys Eigenmann by melanopleura Ellis This taxonomic change caused G. melanopleura as proposed by Eigenmann [9] to become a junior secondary homonym of G. melanopleura of Ellis (1911) because both species were kept in the same genus, Glandulocauda [1]. There are two valid species of Glandulocauda: G. caerulea Menezes & Weitzman and G. melanopleura (Ellis), and our study focus on this latter species, which is the type-species of the genus
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
