Actinopterygii (ray-finned fishes) > Siluriformes
(Catfish) > Mochokidae
(Squeakers or upside-down catfishes)
Etymology: Synodontis: Greek, syn, symphysis = grown together + Greek, odous = teeth (Ref. 45335). More on author: Boulenger.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; benthopelagic; pH range: 6.0 - 7.5; dH range: 25 - ?. Tropical; 24°C - 28°C (Ref. 2059)
Africa: coastal drainages of the Bay of Guinea from Ghana to Gabon (Ref. 82238), including the Pra, Sio, Mono, Niger delta, Kwa Ibo (Ref. 57223), Cross (Ref. 57223, 81251), Wouri, Sanaga (Ref. 81251, 82238), Mungo (Ref. 81251), Lobe and Kribi (Ref. 82238). Possibly also in the Nyong (Ref. 81251). Presence in Volta and Comoe basins (Ref. 82238) unconfirmed (Ref. 57223). Presence in Gabon (Ogooue drainage) questionable (Ref. 78218) and unconfirmed (Ref. 81251).
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 25.8 cm SL male/unsexed; (Ref. 57223)
Morphology | Morphometrics
spines: 0. Diagnosis: gill slits not extending ventrally beyond pectoral-fin insertions; interorbital space less than 50% of head width (Ref. 57223), 58.5-86.6% of snout length (Ref. 81251); post-orbital length at least 60% of snout length (Ref. 57223, 81251). Entire margin of opercle smooth (Ref. 81251). Maxillary barbels longer than head, unbranched, without tubercles and bordered by a distinct, black basal membrane (Ref. 57223, 81251), at least as broad as barbel (Ref. 81251). Outer mandibular barbels with rather long, numerous, simple and thin ramifications, branches of inner mandibular barbels long, subdivided/dichotomous and moderately thin (Ref. 57223). Mandibular teeth rather long (Ref. 57223), movable (Ref. 81251), numbering 21-46 (30 in the lectotype)(Ref. 57223, 81251). Denticulations of pectoral-fin spines weaker on outer than on inner margin (Ref. 57223), with twice as many serrations along anterior edge as posterior (Ref. 81251). Dorsal-fin spine smooth anteriorly, prolonged into short filament, as are almost all of the branched dorsal-fin rays (Ref. 57223, 81251). Humeral process twice as long as deep, pointed and granulose, not keeled ventrally (Ref. 57223, 81251). Adipose fin little developed and low, distinctly separated from rayed dorsal fin (Ref. 57223), base of adipose fin 1.5-3.4 times distance between dorsal fin and base of adipose fin (Ref. 81251). Body covered with spots of about 1 mm in diameter; caudal fin spotted (Ref. 57223, 81251), but without single dark patch at base of each fin lobe (Ref. 81251).
Its electric organ is located dorsally and consists of modified striated muscle (Ref. 10011). Oviparous (Ref. 205). Maximum TL recorded was 37.5 cm (Ref. 57223), maximum SL (for Lower Guinea only?) 16.8 cm (Ref. 81251).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Oviparous (Ref. 205). Distinct pairing during breeding (Ref. 205).
Paugy, D. and T.R. Roberts, 2003. Mochokidae. p. 195-268 In C. Lévêque, D. Paugy and G.G. Teugels (eds.) Faune des poissons d'eaux douce et saumâtres de l'Afrique de l'Ouest, Tome 2. Coll. Faune et Flore tropicales 40. Musée Royal de l'Afrique Centrale, Tervuren, Belgique, Museum National d'Histoire Naturalle, Paris, France and Institut de Recherche pour le Développement, Paris, France. 815 p. (Ref. 57223)
IUCN Red List Status (Ref. 123251)
CITES (Ref. 118484)
Threat to humans
Fisheries: ; aquarium: commercial
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass 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=0.00617 (0.00259 - 0.01467), b=3.09 (2.88 - 3.30), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic level (Ref. 69278
): 2.9 ±0.3 se; based on size and trophs of closest relatives
Resilience (Ref. 120179
): High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.).
Vulnerability (Ref. 59153
): Low to moderate vulnerability (30 of 100) .