pacifici, gen. et sp. nov., is described from the Dagua and Anchicaya Rivers on the Pacific slope of Colombia. The new genus is differentiated from the other genera in the family by the presence of an ossified crucifix-shaped second basibranchial; ectopterygoid bone shaped as an inverted comma, with its distal end narrow and directed medially towards the mesopterygoid; anterior fontanel elongated, reaching a transverse line at sensory canal opening of the sphenotic bone; caudal fin emarginated with rounded edges and ventral lobe more developed than the dorsal lobe; caudal fin with a dark spot from its base and fused with the peduncular spot, covering the anterior three quarters of its length, distal rim totally hyaline. Coloration of the species is described in vivo, and the shared diagnostic characters with the other genera within the Pseudopimelodidae are discussed. The phylogenetic position of the new genus is proposed and new insights in the family interrelationships are presented.Cruciglanis pacifici, um novo gênero e espécie de Pseudopimelodídeo, é descrito para a bacia dos rios Dagua e Anchicaya na vertente do Pacífico colombiano. O novo gênero é diferenciado dos outros gêneros da família pela presença do segundo basibranquial ossificado em forma de cruz, osso ectocterigoide em forma de vírgula invertida, com o extremo posterior estreito e dirigido medialmente ao mesopterigóide; fontanela anterior alongada alcançando a altura da sua linha na horizontal a abertura do canal sensorial do osso esfenótico; nadadeira caudal emarginada com as suas bordas arredondadas e o lóbulo inferior mais desenvolvido do que o superior, nadadeira caudal com uma mancha escura desde sua base e fusionada à mancha peduncular, abrangendo as três primeiras quartas partes do seu comprimento, borda posterior hialina. Descreve-se a coloração da espécie in vivo, e os caracteres diagnósticos compartilhados com os demais gêneros da família Pseudopimelodidae são discutidos. A posição filogenética do novo gênero é proposta e, adicionalmente, uma nova hipótese de interrelações filogenéticas da família é apresentada.
Pseudopimelodus is a Neotropical genus of bumblebee catfish, composed of four valid species occurring in both trans- and cis-Andean rivers of South America. The orogeny of the Andes has led to diversification in the genus Pseudopimelodus in Colombia. This study analyzed partial sequences of mitochondrial cox1 and nuclear rag2 genes to test the hypothesis that the species, nominally recognized as P. schultzi and P. bufonius in Colombia, correspond to more than two different evolutionary lineages. Results indicate high levels of genetic divergence among individuals of nominal P. schultzi and P. bufonius, from trans- and cis-Andean basins in Colombia. In addition, five divergent lineages of Pseudopimelodus were confidently delimited by using a single-locus species-discovery approach and confirmed by species tree analyses. Additionally, molecular-clock dating showed that most diversification processes in Pseudopimelodus took place during the Miocene, when Andean tectonic evolution was occurring in northwestern South America. The present study provides, for the first time, phylogeographic insight into this Neotropical genus.
Two new species of Imparfinis are described from the trans-Andean region of Colombia. Imparfinis timana is diagnosed by having longer anal fin base , in combination with long adipose fin (24.6-31.3% in SL), 5-6 gill rakers on the first ceratobranchial, 42-43 vertebrae and additional measurements. Imparfinis usmai is distinguished by the combination of first ray of dorsal fin longest, but not projected as a long filament, long adipose fin (21.1-27.0% in SL), maxillary barbel exceeding pelvic-fin base, 39-40 vertebrae, upper caudal-fin lobe pointed and longer than lower lobe, lower lobe rounded, 7-8 gill rakers on the first ceratobranchial, as well as additional measurements. Imparfinis timana is only known from río Guarapas, a small tributary of the upper course of the río Magdalena. Imparfinis usmai is broadly distributed in the upper basin of ríos Cauca and Magdalena, and in the lower Patía river basin. The restricted distribution of I. nemacheir to transAndean drainages (Atrato, Magdalena, and Lago de Maracaibo) is also discussed.Duas novas espécies do gênero Imparfinis são descritas da região transandina da Colômbia. Imparfinis timana é diagnosticada por possuir as nadadeiras adiposa e anal compridas (24,6-31,3% e 12,4-15,5% no CP, respectivamente), 5-6 rastros branquiais no primeiro ceratobranquial, 42-43 vértebras, além de outros caracteres de morfometria. Imparfinis usmai é diferenciada pela combinação do primeiro raio da nadadeira dorsal longo, mas não projetado como um filamento comprido, nadadeira adiposa longa (21,1-27,0% na CP), barbilhões maxilares ultrapassando a base da nadadeira ventral, 39-40 vértebras, lóbulo superior da nadadeira caudal pontiagudo e mais longo que o lóbulo inferior, lóbulo inferior arredondado, 7-8 rastros branquiais no primeiro ceratobranquial e outros caracteres de morfometria. Imparfinis timana é conhecida somente para o rio Guarapas, pequeno tributário da bacia do alto rio Magdalena. Imparfinis usmai é amplamente distribuída nas bacias dos rios Cauca, Magdalena e Patía. A distribuição restrita de I. nemacheir nas bacias da região transandina (Atrato, Magdalena e Lago de Maracaibo) é discutida.
Catfishes of the family Astroblepidae form a group composed by 82 valid species of the genus Astroblepus inhabiting high-gradient streams and rivers throughout tropical portions of the Andean Cordillera. Little has been advanced in the systematics and biodiversity of astroblepids other than an unpublished thesis, a single regional multilocus study and isolated species descriptions. Here, we examined 208 specimens of Astroblepus that apparently belong to 16 valid species from several piedmont rivers from northern Colombia to southern Peru. Using three single-locus approaches for species delimitation in combination with a species tree analysis estimated from three mitochondrial genes, we identified a total of 25 well-delimited lineages including eight valid and 17 potential undescribed species distributed in two monophyletic groups: the Central Andes Clade, which contains 14 lineages from piedmont rivers of the Peruvian Amazon, and the Northern Andes Clade with 11 lineages from trans- and cis-Andean rivers of Colombia and Ecuador, including the Orinoco, Amazon, and Magdalena-Cauca basins and Pacific coastal drainages. Results of species delimitation methods highlight several taxonomical incongruences in recently described species denoting potential synonymies.
Two new species of Characidium, C. tatama and C. dule, are described from the biogeographic Chocó region in western Colombia. Both new species are supported by both morphological and molecular data. C. tatama from the San Juan River in the Pacific and C. dule from the Atrato River in the Caribbean portion of Colombia are both distributed in the upper and lower portions of these basins. An extensive comparison with other trans-and cis-Andean species of Characidium was made, in addition to species delimitation, using COI sequences by distinct methods (GMYC, ABGD, bPTP).
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