Heterobranchus longifilis can be distinguished from all other Zimbabwean clariids by having two distinct dorsal fins: a short, rayed dorsal fin and a long adipose fin
. The rayed dorsal fin has no more than 40 rays compared to at least 50 in the other species.
TL: total length, AF: base adipose fin
, CF: base caudal fin, BL: barbeus length, HL: head length, CL: upper caudal fin lobe length, ID: interorbital distance, BD: maximum body depth, ED: eye depth, BW: mouth width, MD: mouth depth.
virolinica) and the presence of pigment on the adipose fin
5B.) Trunk dark tan to brown dorsally, paler ventrally; dark markings in small specimens faded; black pigmentation on jaw, pectoral, and adipose fin
easily visible; dark caudal-fin pigmentation less distinct in larger specimens (>280 mm SL).
"The ratio of hatchery fish to wild fish is about 1:1." On the tributaries and mainstem of the Columbia and the Snake, wild fish (with adipose fins
intact) must remain in the water
The highest Wilks' values were associated with the basal length of anal fin (0.0361), posterior insertion of adipose fin
to posterior insertion of anal fin (0.0576), and the head width at level of occipital (0.0436).
Identifying characteristics include a flap-like adipose fin
, a squared, rounded or slightly forked tail, mottled back and sides, and a slight overbite.
Dorsal profile from anterior margin of snout to origin of dorsal fin insertion slightly convex and very little arched; almost straight at dorsal-fin base and straight from dorsal-fin terminus to adipose fin
; concave at caudal peduncle between adipose and caudal fin; ventral profile convex in slight uniform curvature from inferior mandible to vertical through pectoral-fin basis and almost straight from this point to origin of anal-fin insertion; straight at anal-fin base and concave at caudal peduncle between distal anal and caudal-fin insertion.
through all the photos & diagnostic features--gill raker count, scale rows between lateral line and pelvic process, coloration of adipose fin
and so on) these bigger fish are Hydrocynus brevis, although there are in theory three tigerfish species present--H.
46 to 54, F = 145.3 n = 70 p<3.20 E-19); and from other species from the upper and middle Magdalena drainage by the absence of a lateral band and the presence of a pigmented adipose fin
Scientific monitoring systems - smolt traps, micro tags, genetic marking, adipose fin
clipping - should be employed, otherwise all is guesswork, and high-risk strategy.
Distichodus mossambicus is a distinctive fish, with a deep, compressed body covered with ctenoid scales that also cover the adipose fin
. The rayed dorsal fin is relatively high while the caudal fin is deeply forked and largely covered by scales.