Body significantly wider than its height at pectoral girdle area, progressively compressed from pectoral to caudal peduncle, ventrally flattened from pectoral girdle to anal origin. Sixteen to 20 acicular gill rakers on first arch, 17 – 24 spike-shaped gill rakers on second arch, rakers present on posterior margin of all gill arches. Gill membranes fused, attached to isthmus. Dentary with eyebrow-shaped patch of teeth, separated at midline with sharp teeth. Premaxilla rectangular transversally, moderately long and wide, with sharp teeth. One pair of accessory tooth plates ovate, with sharp teeth. Mouth subterminal, moderately large, with lips moderately thick and lower jaw arched. Nuchal plate crescent-shaped, conspicuously granulated dorsally, moderately long and narrow. Parietosupraoccipital slightly keeled, triangular, with straight lateral margins converging posteriorly, relatively short and moderately wide posteriorly, with posterior margin convex. Pterotic lateral margin markedly convex, sometimes angled. Sphenotic straight laterally, as wide medially as anteriorly. Fleshy portion of dorsomedial groove of neurocranium, affixed to anterior cranial fontanel, evident, reaching or not reaching eyes. Cephalic shield exposed, moderately long and wide on supracleithrum, lateral ethmoid and frontal areas, with thick granulation forming distinct patterns from eyes to parietosupraoccipital process. Osseous bridge formed by lateral ethmoid and frontal moderately long and slender, delimiting a fenestra little evident under the skin. Three pairs of long teretiform barbels maxillary barbel surpassing or not membranous portion of operculum, lateral and mesial mental barbel not reaching posterior margin of gill membrane. Anterior nostril rounded, with fleshy edge, posterior nostril covered by flap of skin, moderately distant to one another and moderately distant to orbit, not connected by fleshy furrow. Head moderately long, wide and high, especially depressed at lateral ethmoid and frontal area, profile elevated posteriorly, convex from mesethmoid to frontal and straight on parietosupraoccipital. Morphometrics and meristics summarized in Tables 2 – 4, 6.
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