Systematics of the Jaguar catfish genus Liosomadoras Fowler, 1940 (Auchenipteridae: Siluriformes)

Abstract

Liosomadoras Fowler, 1940 includes two nominal species: L. oncinus, described from the rio Negro in Brazil, and L. morrowi described from the Peruvian Amazon. Both species are known from only few specimens deposited in fish collections, and information on these fishes is scarce. In order to rectify this situation, diagnoses of the genus and its species and an osteological description of L. oncinus are presented based on recently collected specimens. In addition, the taxonomy of the species of Liosomadoras is reviewed, and L. morrowi is confirmed as distinct from L. oncinus, and also distributed in the Brazilian Amazon. Liosomadoras is hypothesized as a relatively basal genus within Auchenipterinae, sister to all other species of the group, except Asterophysus batrachus and Tocantinsia piresi.Liosomadoras Fowler, 1940 inclui duas espécies nominais: L. oncinus, descrita a partir de exemplares coletados no rio Negro no Brasil, e L. morrowi descrita da Amazônia Peruana. Ambas espécies são conhecidas a partir de poucos exemplares depositados em coleções, e informações sobre esses peixes são raras. Com o intuito de remediar esta situação, diagnoses do gênero e de suas espécies, e uma descrição osteológica de L. oncinus, são apresentadas com base em exemplares recentemente coletados. Além disso, a taxonomia das espécies de Liosomadoras é revista, e L. morrowi é confirmada como distinta de L. oncinus e também distribuída na Amazônia brasileira. Liosomadoras é considerado um gênero relativamente basal em Auchenipterinae, grupo irmão das demais espécies da subfamília, exceto Asterophysus batrachus e Tocantinsia piresi.

Phylogenetic relationships of the South American Doradoidea (Ostariophysi: Siluriformes)

“…Britski & Akama (2011) described Trachycorystes menezesi from the rio Aripuanã, in Brazil; and Akama & Ferraris (2011) described Spinipterus acsi as a new genus and species. Birindelli & Zuanon (2012) revised Liosomadoras, redescribing L. morrowi and L. oncinus. Last year, Sarmento-Soares & Martins-Pinheiro (2013) described Glanidium botocudo; Vari & Ferraris (2013) described two new species of Tatia; and Sarmento- described Centromochlus meridionalis.…”

Quantifying shortfalls in the knowledge on Neotropical Auchenipteridae fishes

“…It is also necessary to highlight the importance of being cognizant of intrinsic features of the natural history of species to better understand what is contributing to the knowledge gaps. The Auchenipteridae family is known by its distinctive habit of using submerged trunks as diurnal shelters (in genera such as Balroglanis , Liosomadoras , Tatia and Trachelyichthys ; Birindelli & Zuanon, 2012) or by foraging at twilight and during the night on the surface of the water (such as the miniature species of Gelanoglanis ; Calegari & Reis, 2017). Because of these peculiarities, collecting fish from this family requires using diverse methods such as manual collecting inside trunks or ichthyoplankton nets.…”

“…According to Ota et al (2015), three factors may be responsible for the increase in description rates of siluriforms from 2001 onwards: Birindelli & Zuanon, 2012) or by foraging at twilight and during the night on the surface of the water (such as the miniature species of Gelanoglanis; Calegari & Reis, 2017). Because of these peculiarities, collecting fish from this family requires using diverse methods such as manual collecting inside trunks or ichthyoplankton nets.…”

Sexual Dimorphism, Length-Weight Relationships, Fecundity, and Diet of the Striped Eel Catfish <i>Plotosus lineatus</i> (Plotosidae) on Taiwan’s Southwest Coast

“…Accordingly, the sex ratio of P. lineatus is a notable phenomenon that warrants exploration. For example, in adult male auchenipterids, the parieto-supraoccipital bone is dorsally concave, and the OS bone forms a closed cylindrical tube and a flat skull [28] [29]. Of the many mechanisms that drive the evolution of sexual dimorphism, the most widely recognized is sexual selection, which enhances the fitness of each sex exclusively concerning reproduction [30] [31] [32] [33].…”