A new Trichomycterus lacking pelvic fins and pelvic girdle with a very restricted range in Southern Brazil (Siluriformes: Trichomycteridae)

Abstract

Trichomycterus tropeiro, new species, is described from the headwaters of the rio das Antas, laguna dos Patos system, Southern Brazil. Trichomycterus tropeiro is distinguishable from other species of the genus by the absence of pelvic fins and pelvic girdle, except from Trichomycterus candidus and Trichomycterus catamarcensis. It differs from these two species in several counts and measurements. The apparent endemism of the species is discussed.

Two new species of Heptapterus (Siluriformes: Heptapteridae) from the Uruguay River basin, Brazil

“…Heptapterus carnatus is geographically restricted to the Araucaria forest plateau ecoregion in southern Brazil and to the upper portions of the Jacuí and Uruguay Rivers. Malabarba et al (2009) (Ferrer & Malabarba, 2011;Tencatt et al, 2016;Lucena et al, 2017;Reis, 2017), all endemic to this area. The description of H. carnatus adds one more species to list of fishes endemic to the Araucaria forest plateau ecoregion, highlighting the importance of aquatic conservation in this region.…”

“…() identified a high degree of fish endemism in this region, listing eight species as endemic, namely: Astyanax brachypterygium Bertaco and Malabarba 2001, Astyanax cremnobates Bertaco and Malabarba 2001, Bryconamericus patriciae da Silva 2004, Cnesterodon brevirostratus Rosa and Costa 1993, Eurycheilichthys pantherinus (Reis & Schaefer 1992), Jenynsia eirmostigma Ghedotti and Weitzman 1995, Pareiorhaphis eurycephalus Pereira and Reis 2002 and Pareiorhaphis vestigipinnis (Pereira & Reis, 1992). Additional species have since been described for the Araucaria forest plateau, such as Trichomycterus tropeiro Ferrer and Malabarba , Corydoras froehlichi Tencatt, Britto and Pavanelli , Astyanax taurorum Lucena, Zaluski & Lucena , Eurycheilichthys castaneus Reis , E. planus Reis , E. vacariensis Reis , E. coryphaenus Reis (Ferrer & Malabarba, 2011; Tencatt et al ., 2016; Lucena et al ., 2017; Reis, 2017), all endemic to this area. The description of H. carnatus adds one more species to list of fishes endemic to the Araucaria forest plateau ecoregion, highlighting the importance of aquatic conservation in this region.…”

Taxonomical study of Trichomycterus (Siluriformes: Trichomycteridae) from the Ribeira de Iguape River basin reveals a new species recorded in the early 20th century

“…Morphometric data were taken point to point with a digital calliper (precision 0.1 mm). Nomenclature of measurements follows: Tchernavin () for length of barbels; Wosiacki and de Pinna () for length and depth of caudal peduncle and for supraorbital pore s6 distance; Ferrer and Malabarba () for scapular girdle width; Ferrer et al . () for length of interopercular patch; and Costa () for the other measurements.…”

“…All species examined and incorporated in the molecular analysis (voucher specimens) were identified or validated by comparing with type specimens, original descriptions (i.e., Ardila Rodríguez, 2016, 2018; Barbosa & Costa, 2010;Fernandez & Chuquihuamaní, 2007;Fernández & Miranda, 2007;Fernández & Vari, 2009;García-Melo et al, 2016;Lezama et al, 2012) and other works with informative data (i.e., Bizerril, 1994;Datovo et al, 2012;Donin, 2019;Eigenmann, 1918;Ferrer & Malabarba, 2011Nascimento et al, 2017;Terán et al, 2017;Wosiacki, 2005;Wosiacki & Garavello, 2004;Wosiacki & Oyakawa, 2005), except for the genetic sequences available in GenBank obtained by Nascimento et al (2017)***, Ochoa et al (2017aOchoa et al ( , 2017b)* and Pereira et al (2011)**. In these cases, the taxonomic identifications provided by the respective author(s) were adopted and their authorship along the text and in the phylogenetic tree was annotated using asterisks (see earlier).…”

“…Morphometric data were taken point to point with a digital calliper (precision 0.1 mm). Nomenclature of measurements follows: Tchernavin (1944) for length of barbels; Wosiacki and de Pinna (2008) for length and depth of caudal peduncle and for supraorbital pore s6 distance; Ferrer and Malabarba (2011) for scapular girdle width ;Ferrer et al (2015) for length of interopercular patch; and Costa (1992) for the other measurements. Osteological information regarding the new taxon was obtained from two c&s specimens, cleared and counterstained according to procedures described by Taylor and van Dyke (1985) and posteriorly dissected.…”