A new genus and species of whiptail armored catfish (Siluriformes: Loricariinae) from southern Venezuela.

A new genus and species of whiptail loricariid catfish belonging to the Pseudohemiodon group is described with 12 specimens captured from the upper Orinoco River and Casiquiare River, Amazonas State, Venezuela. The specimens show delicate and fragile appearance, and are small (largest specimen 74.3 mm SL). The new species has external morphological characters that support its inclusion in the Pseudohemiodon group; however, its mouth morphology is distinctive and unique with features not observed in any species of that group, nor in any other species included in tribe Loricariini or in subfamily Loricariinae. The distinctive buccal characters include: 1) barblets on upper lip border and the maxillary barbel included and interconnected by translucent membrane, leaving the tips free; 2) lower lip surface covered with elongated, cylindrical, unbranched, and fleshy barblets, which resemble filaments, some of them surpassing the border of lower lip. The comparative analyses carried out determined that the recently described species Rhadinoloricaria papillosa has the same two diagnostic buccal characters observed in the new species; therefore it is transferred to the new genus.

The genus Pseudohemiodon (Siluriformes, Loricariidae) in Ecuador, with the description of a new species.

At the Fish Collection of the Museo de la Escuela Politecnica Nacional (MEPN), Quito, the specimens of the genus Pseudohemiodon were revised and three species were identified. The three species inhabit the Amazon versant of Ecuador. Chronologically the species are: P. lamina (Gnther 1868) originally described from Xeberos (Jeberos), Peru; P. apithanos Isbrcker Nijssen 1978, originally described from the Conejo River, Putumayo River system, Ecuador, and a new species described herein. The new species was caught in the Aguarico River, Napo River system, and is represented by two small sized specimens. It is distinguished from all congeners by the combination of the following characters: abdomen totally covered with small to medium-sized, irregularly shaped plates; absence of small plates, anterior to gill openings; eyes relatively small, and six to seven dark transverse bands, posterior to the dorsal-fin. Isbrcker Nijssen (1978) indicate the presence of P. laticeps (Regan 1904) in Ecuador; however we didnt find any specimen of this species. The specimens that could potentially be identified as P. laticeps are large sized specimens of P. apithanos. Some external morphological characters, morphometric and meristic data of analyzed specimens of P. apithanos and P. lamina are provided.

New finding of Rhadinoloricaria macromystax (Siluriformes: Loricariidae): redescription of the genus and description of a new species from Ecuador.

The fish collection from the Museum of Escuela Politécnica Nacional, Quito, Ecuador, has nine lots with 12 specimens assigned to genus Rhadinoloricaria. Specimens come from the Napo and Pastaza rivers, Amazon River basin, eastern Ecuador. One specimen matches accurately with figures and original description of Loricaria macromystax Günther, 1869, type species of Rhadinoloricaria. After 150 years, this is the first secure identification of the species, which allowed an accurate description of the genus Rhadinoloricaria, and the discovery of a new species from Ecuador, described herein. In addition, using available specimens, figures and literature, a comparative analysis on external morphology was performed among the eight species included in Rhadinoloricaria. The analysis documented significant differences between them, in some morphological external characters and in buccal ornamentation. The results suggest that the eight species can be grouped into three or four genera. Rhadinoloricaria, in strict sense, has two species. Apistoloricaria is considered a valid genus, and include the four species previously assigned to it. Rhadinoloricaria bahuaja and R. rhami do not belong to the known genera in the Pseudohemiodon group. At this time, available data suggests that both species could continue included in 'Rhadinoloricaria', waiting further analyses to solve their generic status. Results support the use of buccal ornamentation patterns alone or combined with some morphological characters as valuable tool for generic identification within Loricariini.

A new species of Microglanis (Siluriformes: Pseudopimelodidae) from the Pacific slope of Ecuador

ABSTRACT A new species of catfish is described from the Esmeraldas River Basin, Pacific slope, northern Ecuador. Tentatively included in Microglanis, represents the second species of the genus inhabiting the Trans-Andean region. The new species is distinguished from known congeners by a unique combination of external characteristics: head and body color pattern, uniform, pale brown, yellowish or grayish, without any kind of blotches, bands or dots, only a lunate transverse band, dark or black, at caudal-fin origin; adipose-fin origin and forward without lighter or luminous areas. Compared with M. variegatus, the new species has morphometric differences, such as the distances between dorsal and pelvic fins, and between posterior nostrils. Some osteological characteristics are compared with those observed in species of Pseudopimelodidae inhabiting the Pacific versant of Colombia and Ecuador and with some other species of Microglanis.

RESUMEN Se describe una nueva especie de bagre para la cuenca del río Esmeraldas, vertiente del Pacífico, en el norte de Ecuador. Incluida tentativamente en Microglanis, representa la segunda especie del género que habita en la región transandina. La nueva especie se distingue de los congéneres conocidos por una combinación única de características externas, que incluyen: patrón de color de la cabeza y el cuerpo, uniforme, marrón pálido, amarillento o grisáceo, sin ningún tipo de manchas, bandas o puntos, excepto una banda transversal alunada, oscura o negra, en el origen de la aleta caudal; origen de la aleta adiposa y región anterior sin áreas más claras o luminosas. En comparación con M. variegatus, la nueva especie tiene diferencias morfométricas, como las distancias entre las aletas dorsal y pélvica, y entre las narinas posteriores. Algunas características osteológicas se comparan con las observadas en especies de Pseudopimelodidae que habitan en la vertiente del Pacífico de Colombia y Ecuador, y en algunas otras especies de Microglanis.

A new species of whiptail armored catfish, genus Pseudohemiodon (Siluriformes: Loricariidae) from the Orinoco River basin, Llanos region of Colombia and Venezuela

A new species of whiptail armored catfish belonging to the genus Pseudohemiodon is described. The new species inhabits aquatic systems of the Orinoco River basin, mostly in the Llanos region of Colombia and Venezuela. Previously, it had identified as P. laticeps erroneously. The genus Pseudohemiodon includes seven known species inhabit Amazon and Paraná-Paraguay-Uruguay rivers basins. The new species is distinguished from congeners by the combination of the following characters: abdomen totally covered; area in front of gill opening without plates, ventrally; dorsal body color pattern without transversal dark bands, mostly in the caudal peduncle; head with straight sides; head and caudal peduncle narrower.(AU)

Se describe una nueva especie de bagre corroncho cola de látigo perteneciente al género Pseudohemiodon. La nueva especie habita los sistemas acuáticos de la cuenca del río Orinoco, principalmente en la región de los Llanos de Colombia y Venezuela. Anteriormente, fue identificada como P. laticeps de forma errónea. El género Pseudohemiodon incluye siete especies conocidas que habitan en las cuencas de los ríos Amazonas y Paraná-Paraguay-Uruguay. La nueva especie se distingue de todos sus congéneres por la combinación de los siguientes caracteres: abdomen totalmente cubierto; sin placas delante de la abertura branquial, ventralmente; patrón dorsal de coloración del cuerpo sin bandas oscuras transversales, principalmente en el pedúnculo caudal; lados de la cabeza rectos; cabeza y pedúnculo caudal más estrechos.(AU)