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Dorsal spines (total): 1-1; Dorsal soft rays (total): 6-6; Anal spines: -0; Anal soft rays: 11-12. Diagnosis: postcleithral process weakly expressed or absent; upper jaw extending beyond lower jaw; 14-16 gill-rakers on first arch; premaxillary and palatal toothplates with small and tightly packed teeth; vomerine toothplates widely separated and narrower than those on pterygoids; supraoccipital broad and contacting predorsal plate; body width at pectoral fin insertions 4.9-5.3 times in standard length; interorbital width 3.0-4.1 times in head length; distance between posterior nares 4.0-4.8 times in head length; maxillary barbels 4.1-5.5 times in standard length; distance between posterior margins of adipose fin and hypural plate 5.1-6.0 times in standard length (Ref. 75075).
Description: body deepest at vertical through dorsal fin spine origin, widest across pectoral girdle; dorsal head profile evenly sloping from pointed snout to posterior limit of supraoccipital, whereupon profile curves sharply to base of a short, stout dorsal fin spine bearing several small, widely separated serrae; 1st and 2nd branched dorsal fin rays approx. 1.5 times longer than spine creating a tall and flame-shaped fin; dorsal profile from dorsal fin spine to anterior limit of adipose fin flat to slightly concave, sloping gently; adipose fin low with free and rounded posterior lobe; dorsal profile sloping down towards caudal peduncle through adipose fin, beyond which procurrent rays of caudal fin slope steeply upwards to curved upper caudal fin lobe; caudal fin lobes pointed, caudal fin with 17-18 branched rays; procurrent rays of lower caudal fin lobe sloping steeply upwards to join ventral profile anterior of posterior limit of adducted anal fin; anal fin base short and embedded in adipose tissue; anal fin origin well posterior of posterior limit of adducted pelvic fin and directly beneath to slightly posterior of adipose fin origin; ventral profile between posterior limit of anal fin and anterior limit of pelvic girdle sloping gently upwards; pelvic fins rounded to spatulate, with broad bases and short unbranched rays; origin of pectoral fin spine closer to longitudinal line than pelvic fin; pectoral fin small and sharply pointed, with stout, gently curved spine bearing 10-13 (increasing with length) strongly recurved serrae; ventral profile of chest and throat flat and sloping upwards less steeply than dorsal head profile; mandibular barbels widely separated, inner pair originating well anterior of outer pair; surface of throat and buccal cavity folded with deep notch below hyoid; upper lip extending beyond lower, barely exposing premaxillary toothplate; corner of mouth with thick rictal fold forming base of narrow, flattened maxillary barbel; lateral profile of snout bluntly pointed; in dorsal view, head narrows gradually from pectoral girdle to mouth corner, whereupon it angles sharply and curves gently to median; head a trapezoid wedge with flattened sides and dorsum; orbit with free margin not interrupting dorsal profile in lateral view; dorsum of head covered with skin beneath which skull roof variably ornamented with radiating ridges and lines of small rugosities converging posteromedially; broad and deep fontanelle ridged anteriorly with irregular rugosities posteriorly, extending from midway between nares to just behind the posterior limit of orbit; dorsum of supraoccipital process broad, covered with rugosities forming irregular lines and with shallow notch posteriorly; anterior nares placed just posterior of upper lip and placed slightly wider than posterior nares, each bearing a simple nasal barbel reaching approx. anterior limit of orbit; cleithrum covered mostly by opercular flap, sigmoidal posterior margin, without postcleithral process; opercle broadly triangular, flat to slightly concave posterior margin, with radiating and branching striae converging on anteriormost corner; gill rakers on first arch broad, flattened and simple; premaxillary toothplate covered with small teeth of uniform size and density, plate fairly uniform width, narrowing slightly at medial junction and following snout profile before terminating anterior of mouth corner; small mandibular teeth of uniform size and density separated by medial septum, following the anterior profile of lower jaw and narrowing distally prior to their termination at mouth corner; anterior (vomerine) toothplates of palate broadly separated by median gap, straight, narrower than pterygoid toothplates, of even width with squared ends; posterior (pterygoid) tootplates of palate meet anterior plates but remain distinguishable, bean to tear-drop shaped narrowing posteriorly to rounded limits; teeth of palatal toothplates small, of uniform size and density (Ref. 75075).
Coloration: preserved: unpigmented venter gives way to scattered brown chromatophores on flanks increasing in density dorsally becoming reddish-brown to eventually dark brown mid-dorsally; axillary region with lowest density of chromatophores, skin covering junction of epaxials and posterodorsal margin of skull exhibits narrow band of dark pigment; dorsal surface of pectoral fin, maxillary barbel and nasal barbel light below and dark above; chromatophores of dorsal fin increasing in density distally; adipose fin uniformely covered with light scattering of chromatophores; caudal fin in smaller specimens with chromatophores concentrated on medial branched rays of each lobe and less so on upper-, lower- and medial-most branched rays creating 2 diffuse bands terminating short of tips; caudal fin pigmentation indistinct and unifrom on larger specimens; pelvic and anal fins lacking pigment (Ref. 75075). |