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Teleostei (teleosts) > Characiformes (Characins) > Characidae (Characins; tetras) > Stevardiinae
Etymology: Knodus: Greek, knodon, -ontos = knife, sword (Ref. 45335); geryi: Named after Jacques Géry, in recognition of his enormous contribution to the knowledge of the characiform fishes.
Eponymy: Dr Jacques Géry (1917– 2007) was a French physician and ichthyologist. [...] (Ref. 128868), visit book page.

Environment: milieu / climate zone / depth range / distribution range Ecology

Freshwater; benthopelagic. Tropical

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South America: rio do Peixe in the upper rio Paraguay basin, Brazil.

Size / Weight / Age

Maturity: L_m ? range ? - ? cm
Max length : 6.5 cm SL male/unsexed; (Ref. 55831)

Short description Identification keys | Morphology | Morphometrics

Dorsal soft rays (total): 10; Anal soft rays: 18 - 20; Vertebrae: 38 - 39. Differs from all congeners and from all remaining characid fishes by having two symmetric, large dark blotches basally on caudal fin lobes (Ref. 55831).

Inhabits small river with transparent waters, very channeled and relatively deep (> 2 m deep in some points), having both rapids and waterfalls (Ref. 55831). Feeds on vegetal matter and insects (Ref. 55831).

Life cycle and mating behavior Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae

Main reference Upload your references | References | Coordinator | Collaborators

Lima, F.C.T., H.A. Britski and F.A. Machado, 2004. New Knodus (Ostariophysi: Characiformes: Characidae) from the upper Rio Paraguay basin, Brazil. Copeia 2004(3):577-582. (Ref. 55831)

IUCN Red List Status (Ref. 130435: Version 2024-1)

Least Concern (LC) ; Date assessed: 07 November 2018

CITES

Not Evaluated

CMS (Ref. 116361)

Not Evaluated

Threat to humans

Harmless

Human uses

Fisheries: of no interest

FAO - Publication: search | FishSource |

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Estimates based on models

Phylogenetic diversity index (Ref. 82804): PD₅₀ = 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].

Bayesian length-weight: a=0.00912 (0.00496 - 0.01677), b=3.03 (2.87 - 3.19), in cm total length, based on LWR estimates for this species & (Sub)family-body (Ref. 93245).

Trophic level (Ref. 69278): 3.2 ±0.40 se; based on food items.

Resilience (Ref. 120179): High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.).

Fishing Vulnerability (Ref. 59153): Low vulnerability (10 of 100).

Knodus geryi Lima, Britski & Machado, 2004