Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Siluriformes
(Catfish) > Mochokidae
(Squeakers or upside-down catfishes)
Etymology: Microsynodontis: Greek, mikros = small + Greek, synodon = with the teeth growing all together (Ref. 45335); nasutus: Species name from the Latin nasutus, meaning large nosed, in reference to the long snout of this species (Ref. 52369).
Environment / Climate / Range
Freshwater; demersal. Tropical
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 3.7 cm SL male/unsexed; (Ref. 52369)
Morphology | Morphometrics
soft rays: 10 - 11;
Vertebrae: 36. Body compressed (Ref. 52369). Predorsal profile gently convex; postdorsal body sloping gently ventrally (Ref. 52369). Head depressed and broad, broadly rounded when viewed laterally and with rounded snout margin when viewed from above (Ref. 52369). Eye ovoid, horizontal axis longest (Ref. 52369). Distinguished from other Microsynodontis species by having a longer snout, 50.0-53.3% of head length (Ref. 52369). %Mouth inferior and crescent-shaped; lips plicate (Ref. 52369). Barbels in three pairs; maxillary barbel long and slender, extending to just beyond base of last pectoral-fin ray; inner mandibular-barbel origin close to midline, extending to base of pectoral spine and with 2 short, thin branches on anterior half and 3-5 long, thin branches on posterior half; outer mandibular barbel originates posterolateral of inner mandibular barbel, extending to middle of pectoral-fin base and with 3-5 long, thin branches (Ref. 52369). Gill openings narrow, extending from immediately ventral to posttemporal to immediately ventral to base of pectoral spine (Ref. 52369). Dorsal fin located at anterior third of body, with convex margin; dorsal-fin spine long, stout and slightly curved, smooth on both anterior and posterior margins (Ref. 52369). Adipose fin moderately long; margin slightly convex for entire length and posterior end deeply incised (Ref. 52369). Caudal fin rounded, with i,5-6,5-6,i principal rays (Ref. 52369). Anal-fin base located ventral to posterior half of adipose fin, with iv-v,6 rays and convex margin (Ref. 52369). Pelvic-fin origin at vertical ventral to posterior end of dorsal-fin base, with slightly convex margin (Ref. 52369). Pectoral-fin spine slightly curved and stout; anterior spine margin with 16-22 small serrations along entire length of spine, serrations antrorse on distal two thirds and anteriorly directed on proximal third; posterior spine margin with 7-9 strong serrations along entire length (Ref. 52369). Lateral line complete and midlateral (Ref. 52369). Dorsal and lateral surfaces of head and body medium brown, fading to cream or light grayish brown on ventral third of body, belly, and ventral surface of head in preserved specimens (Ref. 52369). Snout with a series of cream spots delineating anterior and posterior nares; cheek region with one or two cream spots immediately ventral to orbit; cream band encircling nape at supraoccipital (Ref. 52369). Dorsal third of body with series of four cream vertical bar-shaped marks extending beyond lateral midline of body: first at middle of dorsal-fin base, second at adipose-fin origin, third at middle of adipose-fin base and last on caudal peduncle immediately posterior to adipose fin (Ref. 52369). Ventral third of flanks with a longitudinal series of five to seven cream spots or vertical bar-shaped marks (Ref. 52369). Dorsal, pectoral, pelvic and anal fins hyaline and sometimes with one or two rows of faint spots forming longitudinal brown rows; caudal fin with similar series of elongate marks forming two to three irregular columns (Ref. 52369).
Africa: Ogowe River, Gabon (Ref. 52369).
Found in a whitewater river (Ref. 52369).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Ng, H.H., 2004. The Microsynodontis (Teleostei: Siluriformes: Mochokidae) of the lower Guinea region, west central Africa, with the description of eight new species. Zootaxa 531:1-52. (Ref. 52369)
IUCN Red List Status (Ref. 96402)
CITES (Ref. 94142)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.5002 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01288 (0.00569 - 0.02916), b=2.96 (2.77 - 3.15), based on LWR estimates for this (Sub)Family-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.0 ±0.4 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
): High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.).
Vulnerability (Ref. 59153
): Low vulnerability (10 of 100) .