Batrochoglanis

Abstract: The gross morphology of the gas bladder is described and compared for representatives of all valid genera of Pseudopimelodidae (Siluriformes). Cephalosilurus albomarginatus and species of Batrochoglanis, and Microglanis have the most basic form: a large, cordiform gas bladder with a simple internal T-shaped septum. Cephalosilurus apurensis, C. fowleri, and C. nigricauda also have a large, cordiform gas bladder, but they have well-developed trabeculae associated with the internal T-shaped septum, and a pair of well-developed constrictor muscles inserted on the external wall; the latter feature is present in most species of Pimelodidae, but absent in all other catfishes. The monotypic Lophiosilurus alexandri also has well-developed constrictor muscles, and its gas bladder is moderately sized. The species of Pseudopimelodus and Cruciglanis have a diminutive gas bladder partially divided into two lateral sacs without internal communication, and lack constrictor muscles. The parapophysis of the fourth vertebra is a wide and long shelf connected to the dorsal surface of the gas bladder in most pseudopimelodid genera. However, in the species of Pseudopimelodus and Cruciglanis the parapophysis of the fourth vertebra is shorter and has its anterior ramus folded back, partially covering the gas bladder anteroventrally; and the tympanic opening is smaller than in species of the other genera. Five phylogenetic characters are proposed based on the morphology of the gas bladder and associated structures in species of Pseudopimelodidae, and the evolution of those characters in the family is discussed. J. Morphol., 2011. © 2011 Wiley-Liss, Inc.

Abstract: The cephalic and pectoral girdle structures of the pseudopimelodin Batrochoglanis raninus are described and compared to those of a representative of another pseudopimelodin genera, namely Microglanis cottoides, as well as to several other pimelodid and non-pimelodid catfishes, as the foundation for a discussion on the synapomorphies and phylogenetic relationships of the Pseudopimelodinae Our observations and comparisons pointed out two new, additional features that could represent potential Pseudopimelodinae synapomorphies: 1) mesethmoid markedly bifurcated anteriorly; 2) spoon-shaped autopalatine with a somewhat roundish, markedly enlarged dorsoventrally, posterior tip In addition, our observations and comparisons indicate that the subfamilies Pseudopimelodinae, Pimelodinae and Heptapterinae do constitute a monophyletic assemblage, and, thus, contradict the commonly accepted idea that the family Pimelodidae is a polyphyletic group

Abstract: Common names: Bagre manchado, sapo (VEN), giant bumblebee catfish (US). Conservation status: Not protected (Rodríguez and Rojas-Suárez 1999; IUCN 2007). Identification: D I, ii (6)7; A 8; P I, ii 6. Reaches 160 mm SL. Head depressed, large, wider than long, mouth wide, eyes small. Body short, robust, caudal peduncle compressed. Body black or dark brown with light band from dorsal fin onto pectoral fins and scattered irregular black spots, ventrum light. All fin margins whitish. Caudal fin cream with diffuse, black subterminal band. Maxillary barbels dark, mental barbels whitish. Juveniles have more obvious white spots. Originally described as Zungaro mathisoni (Fernández-Yépez 1972). All types lost. Listed as “species inquerenda” by Shibatta (2003), requires new description. Distribution: Aroa, Yaracuy and Tocuyo drainages, Venezuela (RodríguezOlarte et al. 2006b; 2007). Abundance: Extremely low; only four specimens found during five years of sampling (day and night) using electrofishing, hook and line, nets and traps). Habitat and ecology: Known from clearwater piedmont and lowland streams of moderate flow over rocks, near submerged structure (pH 6.4–7.6; conductivity 120–470 μS·cm). Benthic, nocturnal. Probably carnivorous. Reproduction: Unknown. One female ripe just before rainy season (April–May), which is when most species spawn. Threats: Affected by deforestation, agriculture and urban development; which are intense and have notably affected the regional ichthyofauna; this species Environ Biol Fish (2009) 85:61–62 DOI 10.1007/s10641-009-9460-0