Actinopteri (ray-finned fishes) > Siluriformes
(Catfishes) > Amphiliidae
(Loach catfishes) > Amphiliinae
Etymology: Amphilius: Greek, amphi = on both sides + Greek, leios = fat.
More on author: Boulenger.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; demersal. Tropical; 20°C - 24°C (Ref. 12468); 5°N - 3°S
Africa: Lake Edward drainage (Ref. 41590, 103388), Lake George drainage (Ref. 4903, 51677, 103388) and Kagera River drainage, part of Lake Victoria basin (Ref. 103388). Also Rufiji River basin, Rugufu River and Rusizi River (Ref. 46152, 98755). Reports from the upper Congo basin refer to Amphilius frieli (Ref. 103388); those from Lake Victoria drainage in Kenya, Lake Kyoga drainage and Lake Manyara affluents to Amphilius lujani; and those from Lake Rukwa basin and Malagarazi River to Amphilius pedunculus (Ref. 103388).
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 15.0 cm TL male/unsexed; (Ref. 27292)
soft rays: 8 - 11;
Vertebrae: 31 - 33. Diagnosis: Amphilius jacksonii is diagnosed from all other species of the Amphilius jacksonii complex by its more slender caudal peduncle, 4.8-7.9% of standard length vs. 8.1-12.3% (Ref. 103388). It is further distinguished from A. pedunculus, A. frieli, and A. crassus by its longer caudal peduncle, caudal-peduncle length 16.7-20.6% of standard length vs. 13.3-18.8%; and from A. frieli, A. crassus, and A. lujani by its more slender body, body depth at anus 9.6-13.2% of standard length vs. 13.5-17.4% (Ref. 103388). It is further distinguished from A. frieli by having fewer total gill rakers on the first gill arch, 6-9, rarely 10 vs. 10-11, rarely 9 or 12; and from A. ruziziensis by having a wider interorbital width, 26.7-32.0% of head length vs. 23.4-25.1% (Ref. 103388). It differs from other east and southern African species of Amphilius, including the wide ranging A. uranoscopus, in having fewer total vertebrae, a mode of 6+7 principal caudal rays, and a crenulated epidermal fold at the base of the caudal fin; the latter character is shared with A. platychir and at least some other west African Amphilius species (Ref. 51677). Amphilius jacksonii is further characterized by the following combination of characters (but not all unique): dorsal and pectoral spines absent; dorsal fin with 7 soft rays; short adipose fin not adnate with caudal fin; pectoral fin with 8-10 soft rays; anal-fin rays 7-10; forked caudal fin with rounded lobes; 31-33 free vertebrae; and variable, heavily mottled pigmentation (Ref. 51677). It is distinguished from other congeners in the Congo [=Zaire] River, except A. angustifrons and A. notatus, by having fewer total free vertebrae, 31-33 vs. 33-40; from A. angustifrons and A. notatus it is distinguished by fewer pectoral rays, 8-11, mode of 10, vs. 8-9, mode of 9; anal-fin rays, mode of 10 vs. 9; and mensural characters (Ref. 51677).
Rheophilic species; occurs in rivers and streams with moderate current and gradient (Ref. 51677). Mostly associated with upper drainages of rivers; in clear and well-oxygenated water (Ref. 27292). Generally associated with large rocks or mixed cobble and rock substrates (Ref. 51677). Carnivorous, feeds predominantly on benthic aquatic insects (Ref. 51677); insect larvae, worms and other invertebrates are taken (Ref. 27292). Iteroparous, with asynchronous ovarian development (Ref. 51677).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Iteroparous, with asynchronous ovarian development (Ref. 51677).
Seegers, L., 1996. The fishes of the Lake Rukwa drainage. Ann. Mus. R. Afr. Centr., Sci. Zool., 278:1-407. (Ref. 27292)
IUCN Red List Status (Ref. 125652)
Threat to humans
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00447 (0.00177 - 0.01127), b=3.09 (2.87 - 3.31), in cm total length, based on LWR estimates for this Subfamily-BS (Ref. 93245
Trophic level (Ref. 69278
): 3.0 ±0.33 se; based on food items.
Generation time: 5.8 ( na - na) years. Estimated as median ln(3)/K based on 2 growth studies.
Resilience (Ref. 120179
): High, minimum population doubling time less than 15 months (tmax<2; K=0.19-0.39).
Fishing Vulnerability (Ref. 59153
): Low to moderate vulnerability (29 of 100) .
Climate Vulnerability (Ref. 125649
): (0 of 100) .