Elasmobranchii (sharks and rays) > Myliobatiformes
(Stingrays) > Potamotrygonidae
(River stingrays) > Potamotrygoninae
Etymology: Potamotrygon: Greek, potamos = river + Greek, trygon = a sting ray (Ref. 45335). More on authors: Müller & Henle.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; benthopelagic; dH range: 10 - ?; potamodromous (Ref. 51243); depth range - m (Ref. ), usually - m (Ref. ). Subtropical; 24°C - 26°C (Ref. 12468)
South America: Paraná-Paraguay River basin.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 40.0 cm WD male/unsexed; (Ref. 27188); max. published weight: 15.0 kg (Ref. 27548)
Occurs in marshy zones where it is frequently found partially hidden in the sandy bottom. This behavior, associated with its perfect immobility and its capacity to undergo homochromy, makes it practically undetectable to the eye. Like all species of this family, P. hystrix has a tail which is equipped with one or more spines which fall spontaneously and are replaced 2 or 3 times a year. At a length of 4 to 6 cm, the spine is a barbed, flattened skeletal formation inserted dorsally in the middle portion of the tail. Its structure is similar to that of a tooth and appears as an ivory cone covered with enamel. The spine is coated with an extremely toxic mucus produced by the cells of the skin and inflicts very painful wounds (Ref. 27188).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Compagno, L.J.V., 1999. Checklist of living elasmobranchs. p. 471-498. In W.C. Hamlett (ed.) Sharks, skates, and rays: the biology of elasmobranch fishes. Johns Hopkins University Press, Maryland. (Ref. 35766)
IUCN Red List Status (Ref. 124695)
Threat to humans
Fisheries: minor commercial; aquarium: public aquariums
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01000 (0.00244 - 0.04107), b=3.04 (2.81 - 3.27), in cm total length, based on all LWR estimates for this body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.2 ±0.4 se; based on size and trophs of closest relatives
Resilience (Ref. 120179
): Very Low, minimum population doubling time more than 14 years (Assuming Fec<10).
Vulnerability (Ref. 59153
): Very high vulnerability (90 of 100) .