New species of Leporinus (Characiformes: Anostomidae) from the highlands of the Guiana Shield in Venezuela

A new species of Leporinus is described using morphological data and compared to all other species of the family. Specimens were illustrated using digital photograph, measured using digital calipers, and had teeth, scales, and fin rays counted under a stereomicroscope. The new species is distinguished from all other Anostomidae, except Anostomus anostomus, A. brevior, A. ternetzi, Hypomasticus despaxi, Leporinus arcus, and L. striatus, by having four dark longitudinal stripes on body. The new species is distinguished from aforementioned species by having terminal mouth with four teeth on the premaxilla, 12 series of scales around caudal peduncle, and 34 to 36 scales in the lateral line. The new species is remarkably similar to Leporinus arcus, which occurs on the opposite side of Guyana Shield highlands. The new species and L. arcus are possibly closely related to Leporinus gomesi, L. granti, L. lebaili, L. melanostictus, L. nijsseni, and L. santosi.(AU)

Uma espécie nova de Leporinus é descrita usando dados morfológicos e comparações entre todas as espécies da família. Exemplares foram ilustrados com fotografia digital, medidos com paquímetro digital e seus dentes, escamas e raios das nadadeiras foram contados sob estereomicroscópio. A espécie nova distingue-se dos demais Anostomidae, exceto Anostomus anostomus, A. brevior, A. ternetzi, Hypomasticus despaxi, Leporinus arcus e L. striatus, por apresentar quatro faixas longitudinais no corpo. A nova espécie distingue-se das espécies mencionadas por ter boca terminal com quatro dentes no osso pré-maxilar, 12 séries de escamas ao redor do pedúnculo caudal e 34 a 36 escamas na linha lateral. A espécie nova é particularmente similar à Leporinus arcus, que ocorre no lado oposto das terras altas do Escudo da Guiana. A espécie nova e L. arcus, possivelmente, são relacionadas proximamente à Leporinus gomesi, L. granti, L. lebaili, L. melanostictus, L. nijsseni e L. santosi.(AU)

Parodon orinocensis (Bonilla et al., 1999) (Characiformes: Parodontidae): emendations and generic reallocation

During recent studies on Parodontidae, specimens of the Venezuelan species Parodon orinocensis (Bonilla, Machado-Allison, Silvera, Chernoff, López & Lasso, 1999) were examined and a few incongruencies with the original description of the species were noted. Emendations to the descriptions of the jaw teeth and color pattern are presented. Three autapomorphies were also observed and are listed herein. The species is moved from genus Apareiodon to Parodon based on presence of dentary teeth.

Durante estudos recentes sobre Parodontidae, espécimes da espécie venezuelana Parodon orinocencis (Bonilla, Machado-Allison, Silvera, Chernoff, López & Lasso, 1999) foram examinados e reconhecidas algumas incongruências na descrição original. Foram realizadas retificações relacionadas aos dentes das maxilas e ao padrão de coloração. Três autapomorfias foram observadas e são aqui listadas. Com base na presença de dentes no dentário a espécie é transferida do gênero Apareiodon para o gênero Parodon.

Dos nuevas especies de bagres del genero Trichomycterus (Siluriformes: Trichomycteridae) de la Gran Sabana, Escudo de las Guayanas, Venezuela / Two new species of catfish of the Trichomycterus (Siluriformes: Trichomycteridae) gender of the Gran Sabana, Escudo de las Guayanas, Venezuela

Trichomycterus celsae n. sp. and Trichomycterus lewi n. sp. are described from the river Kukenán a tributary of the river Caroní, Orinoco basin, Guyana Shield, Venezuela. The new species are diagnosed within the Guyana Shield Trichomycterus species by a distinctive color pattern. Trichomycterus celsae has a uniform light brown color on dorsum and sides of the body; the ventral surface is yellowish or creamy. Trichomycterus lewi has an irregular pattern of black spots of different sizes on dorsum and sides of the body, the larger spots are located at the posterior part of the body, and, the ventral surface is whitish. The osteology of the new species showed that they belong to the genus Trichomycterus. Osteological features support the external diagnosis of both species, some of them are: in T. celsae, the skull has the fontanels well separated, T. lewi has the fontanels closer and joined by a narrow canal. In T. celsae, the dorsal border of the hyomandibula has a conspicuous notch. In T. lewi, the metapterygoid has a projection on the posteroventral angle. Neural spine of the first preural centra is more elongated in T. lewi