Microsynodontis armatus Ng 2004

Diagnosis: retrorse (proximally directed serrations along proximal 1/3-1/2 of anterior edge of pectoral spine (Ref. 52369, 81251). Body slender, 13.7-15.0% SL; eye 6.7-13.9% HL; snout short, its length 43.1-48.5% HL; supracleithral process not reaching to vertical through posterior-most tip of nuchal shield; adipose fin moderately long, its base 25.9-32.9% SL; caudal peduncle slender, its depth 8.3-9.1% SL (Ref. 81251).Description: body compressed; predorsal profile gently convex; postdorsal body sloping gently ventrally; head depressed and broad, broadly rounded when viewed laterally and with rounded snout margin when viewed from above; eye ovoid, horizontal axis longest; mouth inferior and crescent shaped; lips plicate; barbels in three pairs; maxillary barbel long and slender, extending to just beyond base of last pectoral-fin ray; inner mandibular-barbel origin close to midline, extending to base of pectoral spine and with 2 short, thin branches on anterior half and 3-4 long, thin branches on posterior half; outer mandibular barbel originates posterolateral of inner mandibular barbel, extending to middle of pectoral-fin base and with 3-4 long, thin branches; gill openings narrow, extending from immediately ventral to posttemporal to immediately ventral to base of pectoral spine; dorsal fin located at anterior third of body, with convex margin; dorsal-fin spine short, stout and slightly curved, smooth on both anterior and posterior margins; adipose fin moderately long; margin slightly convex for entire length and posterior end deeply incised; caudal fin rounded, with i,6,5,i principal rays; anal-fin base located ventral to posterior half of adipose fin, with iv,7 rays and convex margin; pelvic-fin origin at vertical ventral to posterior end of dorsal-fin base, with slightly convex margin ; pectoral-fin spine slightly curved and stout; anterior spine margin with 21-27 small serrations along entire length of spine; serrations antrorse on distal two-thirds and retrorse on proximal third; posterior spine margin with 6-12 strong serrations along entire length; lateral line complete and midlateral (Ref. 52369). Both sexes with short (< 0.1 mm) tubercles on dorsal and lateral surfaces of head; caudal fin rounded (Ref. 81251).Coloration: dorsal and lateral surfaces of head and body medium brown, fading to cream on belly and ventral surfaces; medium-sized brown spots evenly scattered over ventral surfaces; snout with a series of cream spots delineating anterior and posterior nares, sometimes coalescing to form cream band running from anterior orbital margin to tip of snout; cheek region with numerous small cream spots ventral and posterior to orbit; cream band encircling nape at supraoccipital; dorsal third of body with series of four cream irregular blotches extending short of lateral midline of body: first at middle of dorsal-fin base, second at adipose-fin origin, third at middle of adipose-fin base and last on caudal peduncle immediately posterior to adipose fin, sometimes coalescing with similar marks ventrally and encircling caudal peduncle as irregular cream band; ventral third of flanks with a series of irregular cream blotches, sometimes coalesced with dorsal markings to form reticulate pattern; dorsal, pectoral, pelvic and anal fins hyaline and sometimes with 1-2 rows of faint spots forming longitudinal brown rows; caudal fin with similar series of elongate marks forming 2-3 irregular columns (Ref. 52369, 81251).

Dorsal spines (total): 2; Dorsal soft rays (total): 6; Analspines: 0; Analsoft rays: 11; Vertebrae: 34 - 35

Found in a blackwater forest stream with sand and leaf litter bottom (Ref. 52369).

Found in a blackwater forest stream with sand and leaf litter bottom (Ref. 52369).

fisheries:

Microsynodontis armatus is a species of upside-down catfish endemic to Gabon where it occurs in the Ivindo River. It was first described in 2004 by Ng Heok Hee.