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Dorsal spines (total): 1-2; Dorsal soft rays (total): 6-7; Anal spines: 0-0; Anal soft rays: 7-10; Vertebrae: 34-39. Diagnosis: This species is distinguished from most of the other species by its more slender form, with standard length larger than 8 times body depth, by the short humeral process, less than 20% of the lateral head length and by the possession of only two or three barbs on the pectoral-fin spines (Ref. 86935). It is distinguished from Zaireichthys mandevillei by the large eye, more than one sixth of the head length, vs. 12 times in head length (Ref. 86935). A dwarf species with an edentate palate (Ref. 57128).
Description: Similar in form to the other species of Zaireichthys, but more slender, and with the upper lip more strongly projecting; body very elongate, 7.5-8.5 times longer than deep (Ref. 57128, 86935). Lateral line long, extending at least as far as the end of the adipose fin and usually to or beyond the middle of the caudal peduncle; skin with minute tubercles (Ref. 86935). Head relatively narrow, with a long, narrow supraoccipital process; humeral process short and blunt; eye moderate, 4.6-5.1 in head length; fleshy flaps of nostrils very short; snout fleshy, flattened ventrally and protruding well in advance on mouth; mouth simple, small, about half head width; three pairs of barbels; maxillary barbels very broadly flanged at base, with relatively short filamentous part, reaching to bases of pectoral fins (Ref. 57128, 86935). Dorsal fin positioned shortly behind head, dorsal I-II, 6-7; adipose fin long and low, not closely approaching procurrent rays of caudal; caudal fin emarginate with the lower lobe appreciably longer than the upper, its longest ray 1.2-1.3 times as long as upper lobe longest ray; usually 6 branched rays in each lobe, but one specimen has 5 in the upper; anal fin with 7-10 rays, 3-4 of which are unbranched, the first often being minute; pectoral fins narrowly rounded, with 7 branched rays; pectoral-fin spine short and relatively weakly developed in comparison with other species of the genus, bearing only 2-3 barbs on its posterior surface; pelvic fins extending about to level of origin of adipose fin (Ref. 57128, 86935). Premaxillary tooth patch broader posteriorly than anteriorly and intended posteriorly; branchiostegal rays 6-7; humeral process of cleithrum short and blunt, running to about level of end of supra-occipital process, without denticulations (Ref. 51287, 86935). Capsules of compound vertebra similar in structure to those of other species bu more tubular and narrowed distally, connected by bony bridge below aorta; vertebral column consisting of 35-37 vertebrae plus the ural complex; ribs 5-6 pairs; first haemal spine on 14th or 15th vertebra; anal fin supported by 8-9 pterygiophores associated with 6-7 vertebrae between 19th and 27th (Ref. 86935).
Colouration: Preserved: yellow brown; dorsal and lateral surfaces of head peppered with small melanophores; five dark patches along dorsal surface at nape, base of dorsal fin, between dorsal and adipose fins, at origin of adipose, below middle of adipose, on caudal peduncle; five dark patches mid laterally, below base of dorsal, above vent, above origin of anal fin, below end of adipose fin, at base of caudal; a dark spot ventro-laterally on each side behind vent; dorsal fin with a faint dark bar at a level just beyond the tip of the spine; caudal fin clear basally but with a broad dark crescentic marking about the central third of fin (Ref. 86935). No broad black collar just behind head (Ref. 51287). |
