>
Gonorynchiformes (Milkfishes) >
Kneriidae (Shellears)
Etymology: Kneria: From Kner, that studied fishes in the Imperial Museum of Vienna, with Jean Natterer (1817) (Ref. 45335); auriculata: Refers to the cup-shaped process of the operculum on the male (Ref. 13721).
More on author: Pellegrin.
Environment: milieu / climate zone / depth range / distribution range
Ecologia
; acqua dolce benthopelagico; potamodromo (Ref. 51243). Tropical; 9°C - 26°C (Ref. 88978); 17°S - 25°S
Africa: most mountain and plateau tributaries of the Zambezi, Pungwe, Buzi, Sabi/Save and Runde/Lundi rivers (Ref. 83372) in Zimbabwe, Zambia and Mozambique. Also in the upper Congo River basin (Lualaba, upper Lualaba, Lake Mweru and Luapula) (Ref. 45616) in Democratic Republic of the Congo and Zambia. A relict southern pocket occurs in the Crocodile (Incomati system), Transvaal (Ref. 7248, 52193). Identity of specimens from the Kafue and upper Zambezi requires confirmation (Ref. 52193). Not recorded from coastal areas (Ref. 5214).
Length at first maturity / Size / Peso / Age
Maturity: Lm ?, range 5 - ? cm
Max length : 7.0 cm SL maschio/sesso non determinato; (Ref. 52193); Età massima riportata: 2.50 anni (Ref. 7248)
Short description
Chiavi di identificazione | Morfologia | Morfometria
Spine dorsali (totale) : 0; Raggi dorsali molli (totale) : 9 - 10; Spine anali: 0; Raggi anali molli: 8 - 11.
Usually found in small headwater streams with fast water associated with rapids and a boulder stream floor, with or without aquatic vegetation (Ref. 12524). Shoals occur in pools of small, clear, silt-free, rocky streams; reported to breathe air and to climb over damp rocks and up the sides of waterfalls during migrations (Ref. 13721, 52959). Can tolerate living out of the water for a long time if conditions are damp (Ref. 246, 5214, 13721). Scrapes diatoms, algae, and detritus from rock surfaces and also takes small aquatic insects such as mayfly nymphs and midge larvae; matures after a year; breeds in spring and summer, larger females bear up to 600 eggs (Ref. 52959). Moves on to flooded grasslands during the rainy season (Ref. 12524, 13337). Males and females have been observed swimming together, apparently joined side by side by means of the males' opercular disc (Ref. 12524).
Life cycle and mating behavior
Maturities | Riproduzione | Spawnings | Egg(s) | Fecundities | Larve
Male and female have been observed swimming side by side apparently joined by the opercular organ of the male; this is probably an adaptation to ensure the efficient external fertilization of ova in a flowing water environment (Ref. 88978). Breeding appears to be correlated with the start and ending of the rainy season; possibly exhibits multiple spawning over a prolonged breeding season (Ref. 88978).
Poll, M., 1984. Kneriidae. p. 129-133. In J. Daget, J.-P. Gosse and D.F.E. Thys van den Audenaerde (eds.) Check-list of the freshwater fishes of Africa (CLOFFA). ORSTOM, Paris and MRAC, Tervuren. Vol. 1. (Ref. 3565)
IUCN Red List Status (Ref. 130435)
Threat to humans
Harmless
Human uses
Pesca: di potenziale interesse; Acquario: Potenziale
Strumenti
Special reports
Download XML
Fonti Internet
Estimates based on models
Phylogenetic diversity index (Ref.
82804): PD
50 = 0.5001 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00389 (0.00180 - 0.00842), b=3.12 (2.94 - 3.30), in cm total length, based on all LWR estimates for this body shape (Ref.
93245).
Resilienza (Ref.
120179): Alto, tempo minimo di raddoppiamento della popolazione meno di 15 mesi (Lm=4.6-4.7).
Fishing Vulnerability (Ref.
59153): Low vulnerability (10 of 100).
