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Clupeiformes (Herrings) >
Dorosomatidae (Gizzard shads and sardinellas)
Etymology: Nannothrissa: Latin, nannus = small + Greek, thrissa, -es = shad (Ref. 45335).
More on author: Regan.
Miljö: miljö / Klimatzon / djupintervall / distributionsområde
Ekologi
; sötvatten pelagiska. Tropical; 6°N - 3°S
Africa: Congo River basin in Democratic Republic of the Congo (Ref. 188, 28136), including Lake Tumba (Ref. 41580, 93833), Ruki River (Ref. 93833) and Ubangui River (Ref. 45441). Reported also from near Kinganga in Lower Congo River (Ref. 42510), but its presence is not confirmed (Ref. 94750).
Storlek / Vikt / Ålder
Könsmognad: Lm ?  range ? - ? cm
Max length : 4.2 cm SL hane/ej könsbestämd; (Ref. 188)
Kort beskrivning
Bestämningsnycklar | Morfologi | Morfometri
Taggstrålar i ryggfenan (totalt) : 0; Mjukstrålar i ryggfenan (totalt) : 12 - 15; Taggstrålar i analfenan: 0; Mjukstrålar i analfenan: 20 - 23; Ryggkotor: 39 - 40. Diagnosis: Body slender, depth about 20% of standard length; scutes beginning at isthmus, or just behind, very strongly keeled, 12-15 pre-pelvic and 6-8 post-pelvic scutes; lower jaw projecting, toothless; no teeth on premaxillae or maxillae; posterior supra-maxilla as deep as maxilla blade and with long slender anterior shaft; lower gill rakers 24-31; pelvic fin with 1 unbranched and 6-7 branched rays, its insertion just before dorsal fin origin; anal fin rays 20-23; scales in lateral series 35-40 (Ref. 188, 2263). It differs from Nannothrissa stewarti in having more gillrakers, 24-31 vs. 20-23, more anal fin rays, 20-23 vs. 17-19, and more scales in lateral series, 35-40 vs. 34-35 (Ref. 188, 2263, 94752).
Body shape (shape guide): fusiform / normal; Cross section: compressed.
Found in rivers and lakes, apparently in both running and still water, often in huge schools (Ref. 188). Feeds on plankton, including unicellular algae, diatoms and especially copepods, but also hydracarians and aquatic insects (Ref. 188, 41580). It breeds in Lake Tumba, ripe fishes being caught in late August and ripe and some spent fishes occurring in about mid-September (Ref. 188, 41580).
Livscykel och parningsbeteende
Könsmognad | Reproduktion | Lek | Ägg | Fekunditet | Larver
Whitehead, P.J.P., 1985. FAO Species Catalogue. Vol. 7. Clupeoid fishes of the world (suborder Clupeoidei). An annotated and illustrated catalogue of the herrings, sardines, pilchards, sprats, shads, anchovies and wolf-herrings. FAO Fish. Synop. 125(7/1):1-303. Rome: FAO. (Ref. 188)
Status på IUCN:s rödlista (Ref. 130435: Version 2025-2)
Hot mot människor
Harmless
Mänskliga användningsområden
Fiskeri: husbehovsfiske
Verktyg
Särskilda rapporter
Ladda ner XML
Internet-källor
Uppskattningar baserade på modeller
Index för fylogenetisk mångfald (Ref.
82804): PD
50 = 0.7500 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00871 (0.00415 - 0.01826), b=3.06 (2.89 - 3.23), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref.
93245).
Trofisk nivå (Ref.
69278): 2.7 ±0.21 se; based on food items.
Resiliens (Ref.
120179): Hög, lägsta populationsfördubblingstid mindre än 15 månader (Preliminary K or Fecundity.).
Sårbarhet i fisket (Ref.
59153): Low vulnerability (10 of 100).
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