A new species of Neoplecostomus Eigenmann & Eigenmann, 1888 (Siluriformes: Loricariidae: Neoplecostominae) from the upper rio Paraná basin

Abstract

Neoplecostomus jaguari, a new neoplecostomine, is described based on material from the rio Jaguari, rio Tietê basin, southeastern Brazil. The new species differs from all congeners by having a conspicuous sexual dimorphism: females with 30-38 teeth in the dentary and 30-39 in the premaxilla, and males with 13-18 and 14-20 teeth, respectively (vs. number of teeth in the dentary and premaxilla approximately equivalent in all other species, except for N. langeanii in the premaxilla); females with larger mandibullary width, 18.5-21.6% HL, males 11.8-15.7% HL (vs.mandibullary width in males and females approximately equivalent); females with teeth longer and thin, males with teeth shorter and robust (vs. teeth similar in other species, except for N. langeaniiin the premaxilla). Furthermore the new species is distinguished from all other species from the upper rio Paraná basin by having a lateronasal plate either forming the border of the nostril or posteriorly displaced (vs. lateronasal plate absent). Finally, other useful character includes four to six plates between the frontal and prefrontal, herein called posteronasal plates (vs.one to three in all other species). An identification key to all Neoplecostomus species is provided.

Gross brain morphology of Hypoptopomatinae and Neoplecostominae (Siluriformes: Loricariidae): Comparative anatomy and phylogenetic implications

“…(2011) and Roxo et al. (2012, 2019), which placed Neoplecostomus ribeirensis as closely related to Isbrueckerichthys , and consistent with other morphological studies (Andrade, 2017; Pereira & Reis, 2017). Specifically, the species was recovered as closely related to N. corumba and N. langeanii within clade 8, as supported by two synapomorphies: (a) Area dorsalis telencephali anteromesial margin extremely convex (char.…”

Life-history features of a rapids-dwelling loricariid catfish from Atlantic forest streams, Brazil

“…However, the location and the environmental disturbances were significant factors in determining the spawning sites. The choice of larger stones for spawning in the rapids demonstrates the caution of N. microps in avoiding stones that can be displaced Sexual dimorphism has been detected in Neoplecostomus species where the males have developed odontodes and an extension in the head region (Zawadzki et al 2008, Roxo et al 2012, Andrade & Langeani 2014. In N. microps, the sexual dimorphism observed in the genital area and in the pelvic fins had been poorly reported in literature.…”

“…2003). The genus is currently represented by 14 species (Andrade & Langeani 2014).The armored catfish Neoplecostomus microps (Steindachner 1877) occurs in the Paraíba do Sul River basin and adjacent coastal rivers (Langeani 1990, Buckup 2007) in southeastern Brazil. Information about the diet and reproductive dynamics of N. microps in mountainstreams of the upper Paraíba do Sul River basin was presented by Braga et al (2008).…”

A new species of Hisonotus (Siluriformes, Loricariidae) from rio São Francisco basin, Brazil

“…Members of Loricariidae are known to have intense sexual dimorphisms (Py-Daniel and Fernandes 2005) as we can observe in species of the genera Ancistrus Kner, 1854 (Sabaj et al 1999), Neoplecostomus Eigenmann & Eigenmann, 1888 (Zawadzki et al 2008; Roxo et al 2012; Andrade and Langeani 2014), Pareiorhaphis Miranda Ribeiro, 1918a (Pereira et al 2007), Hisonotus (Martins and Langeani 2012), Hypostomus Lacepède, 1803 and Chaetostoma Tschudi, 1846 (Nomura and Mueller 1980; Lopez and Roman-Valencia 1996), Farlowella Eigenmann & Eigenmann, 1889 (Retzer and Page 1996) and many other. In Hisonotus vespuccii , we observed five sexual dimorphic characters: the presence of a papilla at the urogenital opening, a pelvic-fin that extends beyond the anal-fin origin, the unbranched pelvic-fin ray supporting a dermal flap on their proximal dorsal surface, the nares opening wider and a body size that seems to be smaller in males than in females.…”