Mastacembelus liberiensis Boulenger 1898

Diagnosis: 92-105 total vertebrae (median 99)[Konkouré River basin: 100-104 (median 102)]; 27+1 up to 34+1 (median 31+1) dorsal spines [Konkouré River basin: 29+1 up to 32+1 (median 31+1)]; no reduction of the pre-opercular spines with increasing length (Ref. 57415). No (exceptionally) up to 1 preorbital spine (Ref. 57415). 1 (very exceptionally) to 5 pre-opercular spines (median 2) (Ref. 55095, 57415). Origin of 1st dorsal spine situated posterior to posterior edge of pectoral fin, 4.8-47.4% HL (m=24.8); distance from anterior border of snout to last externally visible dorsal spine 52.6-61.5% SL (m=57.2), comparable to distance from anterior border of snout to last externally visible anal spine, 53.1-61.9% SL (m=57.8), both decreasing with size; post-anal length 42.3-50.9% SL (m=45.9) and increasing with size, shorter than pre-anal length, 48.5-56.8% SL (m=52.6) and decreasing with size, becoming equal to latter with increasing size; 6-12 caudal fin rays; 7-11 predorsal vertebrae; 37-42 abdominal vertebrae; 0-(+2) in-between vertebrae; 53-64 caudal vertebrae (Ref. 57415).Description: snout blunt; posterior angle of lips situated from about below horizontal middle of posterior nare up to below anterior border of eye; upper corner of gill opening slightly anterior to, or below, dorsal point of pectoral-fin base, both points clearly anterior to ventral point of pectoral-fin base; dorsal point of pectoral-fin base situated largely above upper corner of gill opening; gill opening closed for about half or entire vertical distance between the dorsal and ventral edge of the pectoral-fin base; relatively high number of dorsal spines, with spines increasing in size from first to last; 1 additional very short spine hidden under skin and situated anterior to base of 1st dorsal-fin ray; 2 externally visible anal spines, 1st smaller than 2nd; 1 additional very short spine, hidden under skin, and situated anterior to base of 1st anal-fin ray; preanal length negatively allometric, postanal length positively allometric; lateral-line yellowish-white, continuous in anterior part from head to up to one pectoral-fin length beyond the posterior edge of pectoral fin; remaining, more posterior part of lateral line always clearly discontinuous (Ref. 55095).Coloration: important, geographically related West-East/East-West orientated, intraspecific colour pattern variation has been observed: in general, a more uniform colour pattern with a scarcely developed network on lower sides is observed towards the Western distribution border, including coastal river basins with their mouth situated in Senegal or Guinea, excluding Konkouré River basin specimens which are characterized by a quite unique colour pattern; towards the Eastern distribution border, including all examined specimens originating from coastal river basins with their mouth situated in Liberia, colour pattern is characterized by the presence of a well developed dark brown network enclosing lighter brown, yellowish-white, spots; in between both are Sierra-Leone populations for which there seems to be no such clear consistency between geographical origin of specimens and colour pattern (Ref. 57415). Important size-related colour pattern changes are to be noted: a darkening of median fins with increasing size of specimens being white of overall appearance in small specimens and becoming dark brown of overall appearance; nevertheless, outermost border of unpaired fins remains white with their geographically related colour pattern characteristics (Ref. 57415).

Dorsal spines (total): 28 - 35; Dorsal soft rays (total): 82 - 101; Analsoft rays: 79 - 100; Vertebrae: 92 - 105

Maximum TL observed was 383mm (Ref. 57415).

fisheries: