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The Cusiana River sub-basin has been identified as a priority conservation area in the Orinoco region in Colombia due to its high species diversity. This study presents an updated checklist and identification key for fishes of the Cusiana River sub-basin. The checklist was assembled through direct examination of specimens deposited in the main Colombian ichthyological collections. A total of 2020 lots from 167 different localities from the Cusiana River sub-basin were examined and ranged from 153 to 2970 m in elevation. The highest number of records were from the piedmont region (1091, 54.0 %), followed by the Llanos (878, 43.5 %) and Andean (51, 2.5 %). 241 species distributed in 9 orders, 40 families, and 158 genera were found. The fish species richness observed (241), represents 77.7 % of the 314 estimated species (95 % CI=276.1–394.8). The use of databases to develop lists of fish species is not entirely reliable; therefore taxonomic verification of specimens in collections is essential. The results will facilitate comparisons with other sub-basins of the Orinoquia, which are not categorized as areas of importance for conservation in Colombia.

Trichomycterus steindachneri, new species Figs. 1a, 2a, 3a, 4-5 Holotype. MPUJ 4191, 143.5 mm SL, Colombia, Cundinamarca, Ubaque, vereda Pueblo Nuevo, quebrada El Charco, tributary of quebrada Santa Bárbara, río El Palmar system, río Orinoco basin, 04°31’10.3”N 73°58’44.6”W, 2700 m, 19 Aug 2005, S. Prada-Pedreros, C. Rivera & W. Vanegas. Paratypes. MBUCV-V-35652 (ex MPUJ 2487), 2, 86.7- 88.8 mm SL (MBUCV-CT-1047, 1 CS, 86.7 mm SL), MPUJ 2491, 2, 74.2-77.1 mm SL, same data as holotype, but collected on 20 Aug 2005. MPUJ 2482, 9, 81.1-120.5 mm SL (MBUCV-CT-1053, 3 CS, specimens 2 & 6 completely disarticulated: 105.7-123.9 mm SL, specimen 5 entire: 106.8 mm SL), collected with the holotype. Diagnosis. Trichomycterus steindachneri is distinguished from most Trichomycterus species (except T. cachiraensis Ardila Rodríguez, 2008) by having several broad foramina on cleithrum lamina (Fig. 1a) (vs. cleithrum not pierced). The new species is also distinguishable from most congeners except T. cachiraensis and T. brachykechenos Ferrer & Malabarba, 2013 by having a small posterior cranial fontanel (Fig. 2a), restricted to the parieto-supraoccipital (vs. a long somewhat rectangular fontanel extending anteriorly between frontal bones and posteriorly into anteromedian region of parietosupraoccipital). Trichomycterus steindachneri differs from T. cachiraensis by having 40 or 41 free vertebrae (vs. 37-39), 14-18 ribs (vs. 12), a single upper hypural plate: 3+4+5 (Fig. 3a) (vs. two hypural plates: 3,4+5, Fig. 3b), and by its coloration pattern (ground color dark brown with a thin mid-lateral dark stripe vs. ground color light brown with three lateral rows of small dark spots). Trichomycterus steindachneri can be distinguished from T. brachykechenos by having four rows of premaxillary and dentary teeth (vs. three), 13-14 opercular odontodes (vs. 8-11), 41-43 interopercular odontodes (vs. 22-30), 6-7 branchiostegal rays (vs. 8), anterior portion of sphenotic anterolaterally directed in dorsal view (vs. directed anteriorly), autopalatine with mesial margin straight (vs. concave), 12-16 teeth on ceratobranchial 5 (vs. 21- 22), 11-14 teeth on upper dentigerous plate (vs. 22-25), infraorbital sensory pores i1 and i3 present (vs. absent), 40 or 41 free vertebrae (vs. 37 or 38), 14-18 ribs (vs. 12), first ray of pectoral fin slightly projected as a short filament (Figs. 4-5) (vs. not prolonged as a filament), 7-8 branched pectoral-fin rays (vs. 5-6), dorsal-fin origin at same level of pelvic-fin insertion (vs. at vertical through last third of pelvic fin), anal-fin origin posterior to dorsal-fin base (vs. at vertical through middle of dorsal-fin base), anal fin with seven basal radials (vs. six), procurrent caudal-fin rays 16-21 dorsally and 14-17 ventrally (vs. 15-16 and 10-13, respectively), and by the color pattern of lateral surface of body consisting in background dark brown with a thin mid-lateral dark stripe (vs. background light yellow with superficial layer of densely mottled dark brown). Trichomycterus steindachneri is further distinguished from T. dorsostriatus (Eigenmann, 1918), which also occurs in the río Meta system, by having 40 or 41 free vertebrae (vs. 37), dorsal fin inserted just posterior to neural spine of vertebrae 18 or 19 (vs. vertebra 16), analfin origin behind posterior end of dorsal-fin base, inserted just posterior to hemal spine of vertebrae 22-24 (vs. under posterior portion of dorsal-fin base, just posterior to vertebra 20), a single upper hypural plate (vs. two upper hypural plates), and by the color pattern consisting in a thin mid-lateral dark stripe (vs. a dark band or row of spots from just above the gill-opening to the base of the upper caudal-fin rays). Trichomycterus steindachneri can also be differentiated from the only other species described from western tributaries of the Orinoco in Colombia, T. migrans (río Guaviare system), by its maxillary barbel extending beyond pectoral-fin origin (vs. scarcely reaching this point), anal-fin origin entirely behind dorsal-fin base (vs. at vertical through base of last dorsal-fin ray), and caudal-fin margin slightly rounded (vs. deeply emarginated). Trichomycterus steindachneri can be readily differentiated from remaining congeners described or recorded from Colombia (except T. retropinnis Regan, 1903) by its relatively rare pigmentation pattern consisting in background dark brown with a single thin dark stripe along middle of side of body (vs. background light; either plain, with more than one stripe on lateral surface of body, with a single but wide mid-lateral band, or variably spotted or dotted). Trichomycterus steindachneri differs from T. retropinnis by having first pectoral-fin ray slightly projected beyond margin of fin as a short filament of less than 20% length of adjacent branched ray (vs. projecting as a long filament of ca. 40% length of adjacent branched ray), 7-8 branched pectoral-fin rays (vs. 6 branched rays), pelvic fin covering anus (vs. not reaching anus), relative position of the dorsal fin, expressed as dorsal-fin origin at same level of pelvic-fin insertion (vs. dorsal-fin origin behind distal margin of pelvic fin), and anal-fin origin entirely behind of dorsal-fin base (vs. anal-fin origin under anterior third of dorsal-fin base). Description. Morphometric data presented in Table 1. Body elongated, depressed in anterior region of trunk and becoming gradually compressed to caudal-fin base. Dorsal and ventral profiles straight and parallel, sloping dorsally and ventrally just posterior to dorsal and anal-fin bases, respectively (Figs. 4-5). Cross-section of body elliptical at pectoral-fin insertion with longest axis along horizontal plane. Head depressed, nearly as long as wide, parabolic in dorsal view in specimens shorter than 90 mm SL and square in larger specimens. Lateral portion of head of large specimens (90 mm SL or more) swollen by well-developed jaw muscles, resulting in square aspect of head in dorsal view. Eye small, located dorsolateral, approximately on middle of head length. Eye rim not free, skin covering eye continuous with head skin. Mouth subterminal. Lateral fleshy lobe of lower lip scarcely conspicuous as thickening of lateral portion of lip. Premaxilla with four irregular rows of conical teeth. Dentary with four irregular rows of teeth, similar to those of premaxilla. Anterior nostril small, surrounded by low fleshy thin flap, posterolaterally continuous with nasal barbel. Posterior nostril adjacent to anterior nostril; anterior rim thick, not delimited by fleshy elevated margin; posterior rim not delimited by fleshy flap, and continuous with head surface. Barbels dorsoventrally flattened and tapered distally. Nasal barbel originating from posterolateral margin of anterior nostril, and reaching origin of opercular patch of odontodes. Maxillary barbel extending slightly beyond pectoral-fin origin. Rictal barbel extending to anterior third of interopercular patch of odontodes. Interopercular patch with 41-43 odontodes and 21-23 replacement odontodes, arranged in three irregular rows. Posterior interopercular odontodes of medial row largest. Opercle with 13 or 14 odontodes and 6 or 7 replacement odontodes, approximately disposed in five anteroposterior irregular rows. Posterior most opercular odontodes largest. Branchial membrane free from ishtmus, except anteriorly, and supported by 6* or 7 branchiostegal rays. Branchiostegal rays 3 or 4 to lateral most, distally expanded. Branchiostegal ray 4 or 5 with greatest distal expansion. Anterior margin of mesethmoid cornua straight (Fig. 2a). Anterior fontanel small oval opening just anterior to epiphyseal bar, at level of exit of infraorbital canal from neurocranium. Lachrymal-antorbital associated with anterior section of infraorbital canal (sensory pores i1 and i3). Sesamoid supraorbital long straight rod, without lateral processes. Lateral processes of frontal and sphenotic, where infraorbital canal leaves neurocranium, forming conspicuous lateral tube anterolaterally projected. Posterior fontanel short, two times of anterior fontanel length, oval in shape, and placed entirely on parieto-supraoccipital, but continuous with anterior sagittal suture connecting frontal bones medially. Posttemporo-supracleithrum with long and pointed medial process, extending parallel to anterior margin of Weberian capsule, approaching to basi-exoccipital. Vomer arrow-head shaped, with conspicuous lateral processes posterolaterally directed and long posterior process inserted into anterior process of parasphenoid. Posterior process of parasphenoid long and extending over anterior portion of basi-exoccipital, laterally bordered by two anterior membranous processes of basi-exoccipital. Lateral opening of Weberian capsule at tip of lateral tubular projection, around same length of diameter of capsule. Premaxilla rectangular in shape. Maxilla boomerang shaped, shorter than premaxilla. Articular facet of autopalatine for lateral ethmoid on medial margin of bone, just at posteromedial corner. Anteromedial corner of autopalatine in contact with lateral margin of lateral process of vomer. Metapterygoid laminar and triangular in shape. Hyomandibula articulating anteriorly through dorsoanterior membranous outgrowth with metapterygoid. Interopercular plate supporting odontodes, not extended anteriorly to articular facet for preopercle. Basibranchials 2 and 3 and hypobranchial 1 approximately of same length. Anterolateral process of ossified portion of hypobranchial 3 longer than that of hypobranchial 2. Ceratobranchial 3 with broad notch at proximal portion of posterior margin. Ceratobranchial 5 with 12-16 conical teeth, along anterior portion of medial margin, arranged in two irregular rows. Largest teeth posterolaterally placed. Pharyngobranchial 3 with medial process in posterior tip and broad laminar expansion along medial margin. Upper dentigerous plate with conical teeth arranged in two rows. External row restricted to anterior portion, with 2-4 teeth. Internal row complete, along entire medial margin of plate, with 9-10 teeth. Teeth of internal row larger than those of external row. Supraorbital sensory canal continuous with three pores, and not connected to its counterpart through medial commissure. Sensory pore s1 medially adjacent to anterior nostril. s3 medial to posterior nostril. s6 (epiphyseal) paired, at level of posterior eye rim. Infraorbital sensory canal interrupted in two portions; anterior most portion with sensory pores i1 and i3, laterally adjacent to anterior and posterior nostrils, respectively; posterior most portion connected to supraorbital and otic canals, with sensory pore i10, adjacent to ventroposterior eye rim; i11 posterior to eye at horizontal level of dorsal eye rim. Preopercular canal short with single terminal pore above origin of opercular patch of odontodes. Postotic canal with single pterotic branch and associated pore above opercular patch of odontodes. Lateral line canal very short with two pores above pectoral-fin base. Sensory pore ll1 ventral to main lateral line canal and ll2 terminus of main lateral line canal. Precaudal free vertebrae 9-13 (10) and caudal vertebrae 27-32 (31), totaling 40 or 41* vertebrae. Ribs 14-18* (one CS specimen with one posterior accessory short rib of similar size of penultimate rib, on left side of last supporting rib vertebra). Penultimate rib shortest, around one third of last rib length. First hemal spine on vertebra 16-19 (18). Anus at vertical through anterior third of dorsal-fin base. Pectoral fin with i,7-8* rays. First ray longest, slightly projected beyond margin of fin as short filament. Pectoral complex radial completely cartilaginous (Fig. 1a). Scapulocoracoid anterior process long and pointed. Cleithrum with broad foramina under scapulocoracoid and adjacent to hypocoracoid portion. Pelvic fin with i,4 rays, and lateral splint, its length around half of first ray length. First ray shortest and third ray longest. Inner margins of pelvic-fin bases close to each other. Posterior margin of fin covering anus. Basipterygium with two anterior long processes of around same length or medial process slightly longer. Dorsal fin with 2-4 (3) procurrent rays and ii, 7 principal rays. Shape of fin rectangular in lateral view, posterior margin truncated. Second branched ray longest. Origin of fin at same level of pelvic-fin insertion, at middle of body (including caudal fin). Basal and anterior portions of fin extensively covered by thick integument, anterior most rays (procurrent and unbranched), hardly visible externally. Supporting elements of dorsal fin represented by eight basal radials, inserted between neural spines of vertebrae 18-23, 18-24, or 19-24*, and seven distal radials (last distal radial cartilaginous), associated with second to last basal radials. Anal fin with 3*-5 procurrent rays and ii, 5* or 6 principal rays. Anal fin similar in size and shape to dorsal fin. Second branched ray longest. Origin of fin entirely behind of dorsalfin base. Base and anterior portion of fin similarly covered by thick integument as in dorsal fin. Basal radials seven (MPUJ 2482 paratype specimen of 105.1 mm SL with six basal radials), inserted between hemal spines of vertebrae 22-26, 23-27, 23-28, or 24-28*. Distal radials six, associated with first to penultimate basal radials. First distal radial entirely cartilaginous. Caudal-fin margin slightly rounded. Caudal fin with i, 5+6, i principal rays. Dorsal procurrent rays 16-21*, inserted posterior to neural spine of vertebra PU7-PU10*. Ventral procurrent rays 14-17*, inserted posterior to hemal spine of vertebra PU8-PU10*. Caudal skeleton with two similar plates (Fig. 3a), ventral plate represented by parhypural fused to hypurals 1+2 and dorsal plate by hypurals 3+4+5. Epural absent. Neural spine of preural centrum 1 complete with conspicuous anterior and posterior processes at base of spine. Color in alcohol. Ground color uniformly dark brown on lateral and dorsal surfaces of head and body, including barbels, lower lip, ventral surface of head anterior to gular apex and interopercular patch of odontodes. Ventral surface of branchiostegal membrane and small triangular area delimited anteriorly by gular apex, cream. Ventral surface of body from pectoral region to pelvic-fin insertion cream to light brown, becoming darker posteriorly. Trunk with thin and dark, mid-lateral stripe, extending posterior to opercular patch of odontodes to region below dorsal fin, fading posterior to this point. Some chromatophores clustered along ventrolateral row originating above pelvic-fin insertion to anterior portion of anal-fin base. Few chromatophores forming diffuse blotches, along dorsolateral row, anterior to dorsalfin insertion. Both dorsal and ventral surfaces of pectoral and pelvic fins, pigmented as body, except distal margin. First pectoral-fin ray, basal portion of remaining rays, and basal portion of interradial membrane densely pigmented. Distal tip of fin rays light. Anterior two thirds of rays and interradial membrane of pelvic fin darkly pigmented and distal margin light. Basal integument layer of dorsal and anal fins, including basal portion of rays and interradial membrane, pigmented as body, and distal margin hyaline. Basal portion of caudal fin darkly pigmented. Darkest semicircular halo preceding hyaline distal margin of caudal fin. Distribution and habitat. Trichomycterus steindachneri is known from quebrada El Charco, a tributary of quebrada Santa Bárbara, which drains the east flank of the Eastern Cordillera of Colombian Andes, to empties into río El Palmar of the río Meta drainage, río Orinoco basin (Fig. 6). The collecting site is a typical lotic environment of high altitude (2700 m), about 50 cm wide, with small pools and falls (not higher than 40 cm). Stream banks had dense riparian vegetation, constituted by shrubs and grasses, and dominated by the chusque (Chusquea scandens). Other marginal sections were only covered with pasture. Etymology. The specific epithet steindachneri (adjective genitive masculine singular) is a patronym honoring the prominent Austrian zoologist Franz Steindachner (1834- 1919), in recognition of his dedicated life and significant work in documenting the fish biodiversity, especially that from South America. His profuse morphological descriptions mainly contributed to settle the current standard in ichthyological taxonomic works.

Se comparó la abundancia relativa de Grundulus bogotensis entre dos cuencas y la dieta entre poblaciones de tres cuencas del altiplano Cundiboyacense. Entre marzo y junio de 2006 se realizaron muestreos en 10 localidades utilizando un equipo de electropesca. La abundancia relativa de cada localidad se expresó como el número de individuos capturado por hora en un tramo de 100m. Se utilizó un test de Kruskal-Wallis para determinar diferencias significativas en la abundancia relativa entre cuencas. Para cuantificar la dieta se utilizó el método volumétrico y para determinar el grado de similaridad entre cuencas se recurrió a tres análisis multivariados: análisis de escalonamiento multidimensional no métrico (NMDS), análisis de similaridad (ANOSIM) y análisis de porcentaje de similaridad (SIMPER). Se capturaron en total 675 individuos, empleando 600 minutos de esfuerzo de captura. La abundancia de la especie en la cuenca del río Bogotá fue significativamente menor respecto a la del río Suárez. La composición de la dieta y volumen de ítems entre cuencas fue similar. El material consumido fue de origen autóctono y los ítems más importantes fueron los insectos inmaduros y los microcrustáceos. La abundancia relativa de las poblaciones de G. bogotensis en la cuenca del río Bogotá fue menor que en la cuenca del río Suárez. La cuenca del río Suárez probablemente soporta la mayor abundancia de la especie en todo su rango de distribución y los datos sugieren condiciones favorables para la sobrevivencia de la Guapucha en el lago de Tota. El análisis de la dieta indicó una similaridad mayor al 60% en la utilización del recurso alimentar en las tres cuencas. To compare the relative abundance of Grundulus bogotensis in two river basins and the diet of the populations of three basins in the Cundiboyacense plateau, we sampled 10 localities using electrofishing equipment between March and June 2006. The relative abundance in each locality was expressed as the number of fish caught per hour on a 100m stretch; any significant differences in relative abundance among basins were identified via a Kruskal-Wallis test. To quantify the diet, we used the volumetric method. Similarities between the basins were determined using three multivariate analyzes: nonmetric multidimensional scaling, analysis of similarity and similarity percentages. In the end, we collected a total of 675 individuals during 600 minutes of capture effort. The abundance of this species in the Bogotá river basin was significantly lower compared to that of the Suárez basin. The dietary composition, of autochthonous origin, primarily immature insects and microcrustaceans and the volume of items proved similar between the basins. In conclusion, the dietary analysis indicated a similarity exceeding 60% in the feed resource use for the three basins. The relative abundance of populations of G. bogotensis in the Bogotá river basin was lower than in the Suárez river basin, the latter having, possibly, the greatest abundance of this species throughout its range. The data suggests the most favorable conditions for the survival of the species in Lake Tota. Comparar a abundância relativa de Grundulus bogotensis entre duas bacias e a dieta entre populações de três bacias do planalto Cundiboyacense. Entre março e junho de 2006 foram realizadas coletas em 10 localidades utilizando equipamento de pesca elétrica. A abundância relativa da espécie em cada localidade foi expressa como o número de indivíduos capturados por hora em um trecho de 100m de extensão. Foi utilizado o teste de Kruskal-Wallis para determinar diferenças significativas na abundância relativa entre as bacias. Para quantificar a dieta foi utilizado o método volumétrico e para determinar o grau de similaridade entre bacias foram utilizadas três análises multivariadas: análise de escalonamento multidimensional não métrico (NMDS), análise de similaridade (ANOSIM) e análise de porcentagem de similaridade (SIMPER). No total foram capturados 675 indivíduos, empregando 600 minutos de esforço de captura. A abundância desta espécie na bacia do rio Bogotá foi significativamente menor que na bacia do rio Suárez. A composição da dieta e volume dos itens de alimento entre bacias foram similares. Os recursos consumidos foram de origem autóctone e os itens mais abundantes foram insetos imaturos e microcrustáceos. A abundância relativa das populações de G bogotensis na bacia do rio Bogotá foi menor do que na bacia do rio Suárez. A bacia do rio Suárez provavelmente suporta a maior abundância da espécie em toda a área de distribuição e os dados sugerem condições favoráveis para a sobrevivência da Guapucha no Lago de Tota. A análise da dieta indicou uma similaridade maior a 60% na utilização do recurso alimentar nas três bacias.

Objetivo. Evaluar la relación entre estructura y dieta de la comunidad íctica y la cobertura vegetal riparia (CVR) en dos períodos hidrológicos (PEHI) en riachos de la cuenca del río La Vieja. Materiales y métodos. Las colectas fueron realizadas con electropesca y rapiché en marzo y mayo de 2010. La eficiencia del esfuerzo muestral fue evaluada con el estimador Chao2. La estructura fue analizada mediante los índices: riqueza, dominancia, diversidad y equidad, siendo comparados a través de un ANOVA. Los contenidos gastrointestinales se analizaron usando los índices: coeficiente de vacuidad, frecuencia de ocurrencia, volumétrico e importancia alimentaria. Para analizar la relación entre dieta, PEHI y CVR se utilizó el coeficiente de correlación múltiple (r), el coeficiente de determinación (r²) y un Análisis de Correspondencias Canónicas (ACC). Resultados. Según el estimador Chao2, en la mayoría de los riachos los valores de riqueza íctica en estos ambientes son representativos. No existen diferencias significativas (P>0,05) entre las variables estructurales, el PEHI y las CVR. Según el r y el r², la dieta de la mayoría de las especies no varió en función de la CVR y el PEHI. Sin embargo, según el ACC la dieta varió en función del PEHI, pero no en función de la CVR. Conclusiones. La estructura de la comunidad íctica no presentó cambios según la CVR o el PEHI. Aunque la mayoría de especies no cambiaron de dieta, la comunidad sí presenta cambios en esta en función del PEHI, debido al cambio en la composición; no obstante, los cambios de dieta no se detectaron por tipo de CVR. Objetivo. Avaliar a relação entre estrutura e dieta da comunidade de peixes e a cobertura da vegetação ripária (CVR) em dois períodos hidrológicos (PEHI), em córregos da bacia do Rio "La Vieja". Materiais e métodos. As coletas foram realizadas com pesca elétrica e rapiché em março e maio de 2010. A eficiência do esforço amostral foi avaliada com o estimador Chao2. A estrutura foi analisada através dos índices de riqueza, diversidade, dominância e equidade, e comparados pelo teste ANOVA. A dieta foi analisada pelos conteúdos gastrointestinales, utilizando-se os índices: coeficiente de vacuidade, freqüência de ocorrência, volume e importância alimentar. Para examinar a relação entre dieta, PEHI e CVR foram utilizados o coeficiente de correlação múltipla (r), o coeficiente de determinação (r²) e Análise de Correspondência Canônica (ACC). Resultados. De acordo com o estimador Chao2 na maioria dos córregos os valores da riqueza de peixes nestes ambientes foram representativos. Não existem diferencias significativas (P>0,05) entre as variáveis estruturais, tipo de CVR e PEHI. Segundo o r e o r², a dieta da maioria das espécies variou em função da CVR e PEHI. Embora. Analizando a dieta da comunidade e segundo o ACC, a dieta variou em função do PEHI mas não em função da CVR. Conclusões. A estrutura da comunidade de peixes não apresentou mudanças segundo a CVR ou PEHI. Apesar que a maioria de espécies não apresentaram mudanças em sua dieta, a comunidade sim apresenta mudanças em esta em função do PEHI, devido á mudança na composição; embora, as mudanças na dieta não foram detectadas segundo o CVR.

Se describen tres nuevas especies de Hyphessobrycon grupo heterorhabdus de la cuenca alta del río Orinoco, Orinoquia Colombiana. Hyphessobrycon mavro sp. n. se distingue de los otros Hyphessobrycon conocidos de la cuenca del Orinoco por presentar 4 a 6 dientes en el maxilar, 17 dientes en el dentario, por la longitud del hocico 9,9-15,2 % LC y la ausencia de ganchos en las aletas en machos. Hyphessobrycon niger sp. n. puede distinguirse por presentar nueve dientes en el dentario, cinco escamas con poros en la línea lateral, 25 a 26 escamas en la serie lateral del cuerpo, tres escamas entre la línea lateral y las aletas pélvicas, dos escamas entre la línea lateral y la aleta anal y una línea lateral oscura que se continua para unirse con una mancha peduncular conspicua. Hyphessobrycon acaciae sp. n. se diferencia por presentar 14 dientes en el dentario, cuatro radios simples en la aleta anal y ausencia de ganchos óseos en aletas de machos sexualmente maduros. Se incluye una clave taxonómica para las especies de Hyphessobrycon grupo heterorhabdus presentes en la cuenca del Orinoco. Three new species of the Hyphessobrycon heterorhabdus species group from the upper Orinoco River basin, from the Orinoquia region of Colombia, are described. Hyphessobrycon mavro sp. n. is distinguished from other known Orinoco basin Hyphessobrycon by the following combination of characters: four to six teeth in the maxilla, 17 teeth in the dentary, snout length 9.9-15.2% of head length and the absence of bony hooks on the fins of the males. Hyphessobrycon niger n. sp. can be distinguished by the nine teeth in the dentary, five scales with pores in the lateral line, 25 to 26 lateral scales, three scales between the lateral line and pelvic fins, two scales between the lateral line and the anal fin, and a dark lateral line that fuses with a conspicuous peduncular spot. Hyphessobrycon acaciae sp. n. can be distinguished by the 14 teeth on the dentary, four simple anal-fin rays, and the absence of bony hooks on the fins of the mature males. A key to the Orinoco river basin species of the Hyphessobrycon heterorhabdus group is included.

Objetivo. El presente estudio evalúa las capturas ícticas incidentales de la pesca de especies ornamentales, en términos de abundancia y riqueza, en la zona de influencia del municipio de Puerto Carreño, Vichada, Colombia. Materiales y métodos. Para esto, se realizaron muestreos en los ríos Bita, Orinoco y en Caño Negro, durante el período de aguas bajas, en marzo y abril de 2007. A partir del acompañamiento realizado a las jornadas de pesca ornamental, se colectaron 152 especies entre incidentales y objeto. Se estimó la captura por unidad de esfuerzo (CPUE) y la composición porcentual de las capturas ícticas de las especies objeto versus las incidentales. Resultados. Los valores más altos de CPUE para especies objeto corresponden a los estimados para: Dicrossus maculatus, Hemigrammus rodhostomus, Corydoras cf. melanistius, Peckoltia sp. 2. y Hemiancistrus sp.; Por otro lado, los valores más altos para las especies ícticas incidentales corresponden a: Hemigrammus sp., Moenkhausia sp., Hemigrammus levis, Aphanothorulus cf. ammophilus, Triportheus angulatus y Moenkhausia lepidura. El porcentaje en riqueza para las especies ícticas incidentales varió entre el 92% y 98%. No obstante, el porcentaje en abundancia de las especies objeto fue mayor que el obtenido para las capturas incidentales variando entre 73% y 83%, con excepción de la obtenida en la pesca en los afloramientos rocosos del río Orinoco que fue del 17%. Conclusiones. El impacto de la pesca ornamental sobre las especies de peces capturadas incidentalmente se observa principalmente a nivel de riqueza, pero no a nivel de abundancia. Objective. The present study assesses the incidental fish catches in the fishing of ornamental species in terms of richness and abundance within the influence zone of Puerto Carreño, Vichada, Colombia. Materials and methods. Samplings were carried out in the Orinoco River and Bita River and Caño Negro stream during the low-water season, in March and April of 2007. Target and incidental species collected during the ornamental fishing totalized 152. Catches per unit of effort (CPUE) as well as the percentage composition of fish catches of target vs. incidental species were estimated. Results. The highest values of CPUE of fishes with ornamental value correspond to: Dicrossus maculatus, Hemigrammus rodhostomus, Corydoras cf. melanistius, Peckoltia sp. 2 and Hemiancistrus sp., and the highest values of incidental species were for: Hemigrammus sp., Moenkhausia sp., Hemigrammus levis, Aphanothorulus cf. ammophilus, Triportheus sp. y Moenkhausia lepidura. The richness percentage of incidental species varied between 92% and 98%. However the abundance percentage of target species was always higher than the percentage of incidental catches varying between 73% and 83% with the exception of that obtained in the fisheries of the Orinoco River outcrops that was 17%. Conclusions. The impact of the fishing ornamental fish on species taught incidentally is seen mainly at the level of richness, but not at the level of abundance. Objetivo. Este estudo avalia a captura incidental de peixes produto da pesca ornamental, em termos de abundância e riqueza, na bacia hidrográfica do município de Puerto Carreño, Vichada, Colômbia. Materiais e métodos. Para isso, realizaram-se amostragens nos rios Bita, Orinoco e Caño Negro, durante o período de níveis da água baixos, em Março e Abril de 2007. A partir do acompanhamento direto feito na pescaria ornamental, foram coletadas 152 espécies entre as alvo e as incidentais. Estimaram-se as capturas por unidade de esforço (CPUE) e a composição percentual das capturas das espécies-alvo versus as incidentais. Resultados. Os maiores valores de CPUE para as espécies-alvo correspondem aos estimados para: Dicrossus maculatus, Hemigrammus rodhostomus, Corydoras cf. melanistius, Peckoltia sp. 2 e Hemiancistrus sp., e os maiores valores para espécies incidentais correspondem a: Hemigrammus sp., Moenkhausia sp., Hemigrammus levis, Aphanothorulus cf. ammophilus, Triportheus angulatus e Moenkhausia lepidura. O percentual da riqueza das espécies de peixes incidentais variou entre 92% e 98%. No entanto, o percentual da abundância das espéciesalvo foi maior que aquele pra as espécies incidentais variando entre 73% e 83%, com exceção da obtida na pesca nos afloramentos rochosos do río Orinoco o qual foi de 17%. Conclusões. O impacto da pesca ornamental sobre as espécies de peixes capturadas incidentalmente pode ser observado principalmente ao nível de riqueza, mas não ao nível de abundância.

G. bogotensis has a geographic distribution restricted to the Colombian Cundiboyacense plateau, it is listed as near threatened, and research on its autoecology is scarce. Three collections were made in 2006 in the Fúquene Lake, Cundinamarca, Colombia (5° 27' 55'' N, 75° 46' 19'' W) to describe the habitats occupied by G. bogotensis and to determine its vertical and horizontal distribution. Three sampling zones were selected according to the type of dominant macrophyte (Eichornia crassipes, Schoenoplectus sp. and Egeria densa). In each sampling zone two different cylindrical sampling traps (cloth and PVC) were placed at three depths: surface, mid-depth and bottom. Three replicates were used for each depth and type of trap. Traps were exposed for 24 hours and checked every 6 hours. In addition to the traps, sampling by electrofishing was conducted in each sampling zone during every month. To characterize the study area, physical and chemical variables were analyzed and the structure of phytoplankton, zooplankton, periphyton, and macroinvertebrate communities was studied. Results showed spatial differences on G. bogotensis habitat occupation and differences in captures at each depth, which depend on the dominant type of aquatic vegetation and size of individual. We conclude that only cylindrical cloth traps are suitable to conduct population studies of G. bogotensis. Grundulus bogotensis tiene una distribución restringida al altiplano Cundiboyacense, se encuentra en la categoría "casi amenazada" y son escasos los trabajos realizados sobre su autoecología. Con el objeto de describir los hábitats ocupados por G. bogotensis y determinar su distribución vertical y horizontal en la laguna de Fúquene, Cundinamarca, Colombia (5° 27´ 55" N, 75° 46´ 19" O, 2560m), se realizaron tres muestreos durante el 2006 en tres zonas que se definieron en función del tipo de macrófita dominante (Eichhornia crassipes, Schoenoplectus sp. y Egeria densa). En cada uno de estos puntos se utilizaron dos tipos de trampas (cilíndricas de tela o de PVC) ubicadas en tres profundidades (superficie, medio, fondo); en cada profundidad y tipo de trampa se utilizaron tres réplicas. Las trampas estuvieron expuestas durante 24h y fueron revisadas cada 6h. Adicionalmente se realizaron muestreos con eletropesca en cada uno de los sitios de muestreo y durante cada mes. Para caracterizar las zonas de estudio, se analizaron variables físicas y químicas y se estudió la estructura de las comunidades de fitoplancton, zooplancton, perifiton y macroinvertebrados. De acuerdo con los resultados existen diferencias espaciales en la ocupación de G. bogotensis y diferencias en las capturas realizadas por profundidad que son dependientes del tipo de vegetación acuática dominante y de la talla del individuo. También se concluye que sólo las trampas cilíndricas de tela son adecuadas para realizar estudios poblacionales de G. bogotensis.

RESUMEN: Colombia es uno de los países más ricos del mundo en recursos hídricos y en éste se destacan cinco zonas hidrogeográficas: Caribe, Orinoco, Amazonas, Pacífico y Magdalena-Cauca (IDEAM, 2004). La zona del Caribe incluye ríos muy importantes para Colombia, uno de ellos el Atrato. El río Atrato se forma de la confluencia de dos pequeñas quebradas al occidente de los farallones de Citará, a los 05° 41' de latitud norte y 76° 23' de longitud oeste; vierte sus aguas en el mar Caribe por 16 bocas diferentes, siendo la principal la denominada Tarena, a los 08° 16' de latitud norte y 76° 59' de longitud Oeste. ABSTRACT: Colombia is one of the richest countries in the world in terms of water resources and five hydrogeographic zones stand out: Caribbean, Orinoco, Amazon, Pacific and Magdalena-Cauca (IDEAM, 2004). The Caribbean area includes very important rivers for Colombia, one of them the Atrato. The Atrato River is formed from the confluence of two small streams to the west of the Citará cliffs, at 05 ° 41 'north latitude and 76 ° 23' west longitude; It discharges its waters into the Caribbean Sea through 16 different mouths, the main one being called Tarena, at 08 ° 16 'north latitude and 76 ° 59' west longitude. COL0078704

Este estudio registra por primera vez para Colombia, la presencia del género Roestes en lagunas pertenecientes al plano de inundación de ríos de la cuenca alta del río Caquetá. El género fue colectado en la laguna de Bekochiará de la cuenca del río Orteguaza y en la laguna de Cartagena de Chairá de la cuenca del río Caguán. Los individuos presentan afinidad morfológica con la especie Roestes molossus (Kner, 1860) y su descubrimiento en esta área periférica de la Amazonia confirma la posibilidad planteada por Menezes (1974), de encontrar esta especie en otras cuencas altas de tributarios del río Amazonas, diferentes a las del río Madeira y Juruá.