Actinopteri (ray-finned fishes) > Beloniformes
(Needle fishes) > Belonidae
Etymology: Potamorrhaphis: Greek, potamos = river + Greek, rhaphis = needle (Ref. 45335).
Environment: milieu / climate zone / depth range / distribution range
Freshwater; pelagic; depth range 0 - ? m. Tropical
South America: upper Orinoco and Negro River basins.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 24.6 cm SL male/unsexed; (Ref. 40653)
Morphology | Morphometrics
soft rays: 32 - 39;
Vertebrae: 77 - 85. Most similar to P. guianensis from which it differs most markedly in higher numbers of dorsal and anal fin rays, vertebrae, and predorsal scales. Predorsal scales 109-143, mean 130.5.
Oviparous (Ref. 205). Eggs may be found attached to objects in the water by tendrils on the egg's surface (Ref. 205).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Collette, B.B., 1982. South American freshwater needlefishes of the genus Potamorrhaphis (Beloniformes: Belonidae). Proc. Biol. Soc. Wash. 95(4):714-747. (Ref. 10994)
IUCN Red List Status (Ref. 125652)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82804
= 0.5625 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00389 (0.00119 - 0.01269), b=3.00 (2.75 - 3.25), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.9 ±0.6 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.).
Fishing Vulnerability (Ref. 59153
): Low vulnerability (20 of 100).