Deskripsieng
Description: Based on over 400 specimens from Australian, 30 – 192 mm SL. Data from other localities listed separately. First dorsal spines 6 (45); Maitland and Fortescue River Systems I, 8 (16), I, 9 (43); anal rays I, 7 (2); I, 8 (41), I, 9 (6); other localities: second dorsal rays I, 8 (2), I, 9 (45), I, 10 (2); anal rays I, 7 (1), I, 8 (47), I, 8 (1); longitudinal scale count (LSC) 29 (14), 30 (25), 31 (16), 32 (4); LSC South Africa 29 (3), 30 (4), LSC Bangladesh 30 (1), 31 (2), 32 (1), LSC Madagascar 29 (1), 30 (3), 31 (1); segmented caudal segmented caudal rays 9 / 8 (43); branched caudal rays 12 (13), 13 (11), 14 (34); vertebrae 11 + 16 (4), 10 + 17 (8). Mouth large; reaching to below a point approximately below anterior margin of eye in specimens up to 100 mm SL and to below middle of pupil in larger adults; jaws forming an angle of 28 – 32 ° with body axis; upper margin of upper jaw in line with middle to lower margin of eye. Cheeks narrow, tapering in dorsal view, rarely slightly bulbous. Interorbital narrow, less than eye diameter to about equal to eye diameter. Head moderate, proportion increasing with size, 28.8 – 30.9 % SL in specimens from 50 – 70 mm SL, 30.0 – 32.9 % SL in specimens 71 – 100 mm SL, 30.2 – 33.6 % SL in specimens 101 – 140 mm SL, predicted mean varying from 30.6 – 32.3 % SL over size range examined. Snout broadly rounded in dorsal view; with a notch in side view from upper extension of ascending process of premaxilla well in front of eye; 8.5 – 12 % SL. Eye about 2 – 3 in snout, 6 – 7.8 % SL in specimens below 70 mm SL, 4.6 – 6.8 % SL in specimens above 70 mm SL, relative proportion decreasing with size. Upper jaw 10.4 – 12.7 % SL in specimens below 70 mm SL, 11.4 – 14.6 % SL in specimens above 70 mm SL. Small bump below nostrils absent or indistinct. Anterior nostril at end of short tube, 1 – 2 nostril diameters above upper lip. Posterior nostril well before eye, closer to upper lip than eye, and 1 – 3 nostril diameters from anterior nostril. Preoperculum moderate, distance from end of eye to upper posterior preopercular margin much less than snout length (about half to two thirds snout length); preoperculum with small blunt projection at angle. Postorbital moderate, subequal to from tip of snout to anterior margin to middle of eye. Gill opening broad, reaching to just anterior to posterior margin of preoperculum. Teeth in upper jaw: outer row of teeth conical fixed, slightly enlarged and wideset, 2 – 4 inner rows of smaller depressible, inwardly directed teeth, innermost row larger than middle row and largest anteriorly. Teeth in lower jaw: teeth in outer row conical, slightly enlarged and wideset anteriorly, 2 – 3 inner rows of smaller depressible teeth. Tongue tip bilobed. Gill rakers on outer face of first arch short and triangular, less than one-third filament length. Rakers on inner face of first arch and other arches short and denticulate. Cheek naked. Body covered mostly with large ctenoid scales, ctenii weakly developed or absent on scales at side of nape above operculum, cycloid on anteromedian predorsal region, pectoral base, prepelvic area and midline of belly; belly fully scaled. First dorsal fin low, with rounded to triangular margin, sometimes with second spine filamentous in males, second to sixth (usually second) spines extending beyond other spines when fin depressed; origin of fin well behind pelvic insertion. Second dorsal fin height subequal to first, posterior rays not prolonged in females, reaching about half way to caudal fin when adpressed, elongate in adult males reaching to near end of caudal peduncle. Anal fin slightly lower than second dorsal fin, posterior rays prolonged as in second dorsal fin in mature males, but not reaching caudal fin. Pectoral fin with rounded margin, reaching to well before anus, insertion before pelvic origin, length 19.9 – 25.0 % SL over size range of 50 – 141 mm SL Pelvic disc without thickened rays, much longer than wide, length 19.1 – 22.1 % SL over size range of 50 – 41 mm SL; pelvic fin reaching to or almost to anus in specimen up to 100 mm SL, ending well before anus in larger adults. Caudal fin with rounded margin, 22.0 – 29.8 % SL over size range of 50 – 141 mm SL. Body depth at pelvic origin 13.3 – 17.2 % SL, not showing significant change with size over range of 69 – 132 mm SL. Body depth at anal origin 12.2 – 17.4 % SL over size range of 69 – 141 mm SL. Caudal peduncle depth 8.5 – 10.7 % SL, not showing significant change with size over range of 69 – 132 mm SL. Head pores: Nasal pore immediately above posterior nostril; median anterior interorbital pore present above anterior quarter of eye; median posterior interorbital pore above posterior margin of eye; postorbital pore behind eye present in line with upper margin of pupil; infraorbital pore below postorbital present; lateral canal pore above posterior quarter of preoperculum; terminal lateral canal pore above and just behind posterior preopercular margin; short tube above posterior quarter of operculum, with pore at each end; 3 preopercular pores, upper in horizontal line with lower margin of eye; middle pore much closer to lower than to upper. Sensory Papillae (Figures 1, 2 & 14): Based on specimens 70 – 150 mm SL. Line 1 (before nasal pore) composed of 2 rows of papillae in adults. Line 2 (between nasal pores) curved, composed on single row of papillae, continuous across snout. Line 5 (suborbital) composed of one or two rows of papillae in in specimens between 50 and 110 mm SL. Line 6 (suborbital branch) short, composed of 1 row of papillae. Line 7 composed on single row of papillae posteriorly, 2 - 3 rows anteriorly. Line 9 composed of two rows of papillae; 7 usually with fewer rows than lines 9 and 10. Line 10 composed of 2 – 3 rows. Lines 8 and 11 composed of single row of papillae, straight, reaching to posterior preopercular margin. Line 12 (= Outer POP-mandibular line) composed of 2 rows around chin, single elsewhere, with no gap at end of jaws or with short gap. Line 13 (= Inner POP-mandibular line) composed of 2 – 3 rows of papillae, with no gap at end of jaws, but fewer rows and usually 2 rows along preoperculum. Line 20 composed of one row of papillae, curved backwards ventrally, breaking up into multiple rows anteriorly to form line 23, but only along lower margin of operculum. Line 21 a curved line, composed of single row, rarely with one or two parallel lines above. Line 22 short with vertical branches ventrally and posteriorly. Several vertical papillae rows on belly. A single curved line anteriorly on most body scales (often obscure dorsally and posteriorly). Extensive coverage of chin by papillae, almost reaching lips, but not covering dark mental frenum, usually in 2 patches on each side of chin, with jointed anteriorly, with separate wings posteriorly. Line 15, single row of papillae from end of eye to anterior part of lateral canal tube. Line 17 single row between terminal lateral canal pore and lateral canal tube. Line 19 single behind lateral canal pore behind eye to just behind or above upper preopercular pore ending close to and separate from line 20. Coloration of freshly collected Australian specimens (Figures 15, 30 a, Plate 3): Top of eye usually with a distinct transverse bar extending from interorbital to over iris, sometimes with blotches before and behind but usually only with bar. Head and body brown, pale below. Top of head from interorbital region to end of snout usually darker than rest of head; a dark brown bar from anteroventral margin of eye to middle of lips; an oblique, broad, brown bar from posteroventral margin of eye extending posteroventrally to horizontal bar, extending to posterior preopercular margin, rarely broken into series of 2 – 3 short bars; an horizontally elongate bar behind lips on lower part of preoperculum; operculum brown, with large dark brown or a series of smaller brown blotches anteriorly, with dark pigment of inner surface of operculum showing through and in some darker than spots on outer face of operculum; posterior end of lips usually without pigment, with a dark brown spot on cheek just above posterior end of jaws; pectoral base with long and thin horizontal brown stripe dorsally, extending onto base of pectoral ray; a fainter lower brown horizontal dark brown stripe or elongate spot just above ventral base of pectoral fin; mental frenum dark brown, pigment behind frenum variable as described in diagnosis (Plate 1). Body with scattered brown mottling dorsally; a short, horizontally elongate, brown stripe or oblong spot above and just behind pectoral fin base. Midside with series of large brown spots, covering 2 – 4 scale rows horizontally and usually 2 – 3 rows vertically; midside spots usually horizontally elongate, rounded and large in some specimens; first spot below middle to anterior quarter of first dorsal fin extending ventrally onto sides of belly; second spot varying below space between two dorsal fins to below anterior part of second dorsal fin; third spot below posterior half of second dorsal fin; fourth on anterior part of caudal peduncle; fifth at end of caudal peduncle, followed by triangular to square brown spot (apex forward) on midbase of caudal fin; body with few incomplete to no thin dark stripes, with white above and below on sides. Base of first dorsal fin spine with prominent black spot extending onto the adjoining membrane; overall dorsal fins with a fine pattern of brownish spots ;; caudal fin with 3 – 9 wavy brown to black bands (except on ventral 3 – 4 rays); pectoral fins clear to translucent, rarely with 1 – 2 irregular brownish-gray bands near base of fins, pelvic and anal fins white to gray with no defined pattern. Mature males often with yellow-orange on first dorsal fin and upper and lower parts of caudal fin, distal margin of second dorsal fin pale. Urogenital papillae of males without pigment, females often with black along distal tip. Coloration in preservative: Coloration in alcohol is generally similar to that of freshly collected specimens, except that the dark spots and stripes fade. Specimens stored in alcohol for long periods (> 30 years) are often very faded, but the general patterns are usually discernible (Figures 16 – 29, 30 b). Figure 30 illustrates fading in a specimen over a period of 33 years. Examination of material over 100 years suggests that the basic spotting patterns can fade completely. Preserved specimens from Bangladesh, South Africa and Madagascar have similar coloration to Australian specimens (Figures 25 – 29).
