|Scientific Name:||Potamotrygon henlei|
|Species Authority:||(Castelnau, 1855)|
|Taxonomic Notes:||Sometimes misidentified with P. leopoldi or P. motoro. Needs correct identification and reliable diagnosis in order to control the ornamental fish trade in Amazonas, Pará and Tocantins States.|
|Red List Category & Criteria:||Least Concern ver 3.1|
|Assessor(s):||Rincon, G. (SSG South America Regional Workshop, June 2003)|
|Reviewer(s):||Musick, J.A., Kyne, P.M., Cavanagh, R.D. & Fowler, S.L. (Shark Red List Authority)|
This endemic freshwater stingray was assessed as Data Deficient in the 2000 Red List. Improved information has resulted in the species being downlisted to Least Concern.
Potamotrygon henlei is endemic to the Tocantins-Araguaia River Basin, Brazil, with its primary distribution along the Rio Araguaia and lower Rio Tocantins. This species has not been negatively affected by the damming of the lower Tocantins, in fact there has been a significant population increase in the Tucuruí Reservoir (probably due to an increase in prey), hence this updated assessment of Least Concern. However, given that the species is collected in the unregulated ornamental fish trade, is subject to persecution in some areas and may be affected in other parts of its range by habitat degradation due to illegal mining activities, ongoing monitoring of these threats and its population status are required.
|Range Description:||A black-backed stingray endemic to the Rio Tocantins and Rio Araguaia.|
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||An important population increase occurred after the construction of the Tucuruí dam, lower Rio Tocantins.|
|Habitat and Ecology:||It seems to prefer mud bottoms where it hunts gastropod molluscs, their most important food item (Pantano-Neto 2001). Maximum size 104.2 cm total length (TL) (71 cm disc width (DW)). Females mature at approximately 80 to 85 cm TL (around 50 cm DW). Ovoviviparous, number of young ranges from 1 up to nine embryos a litter and number of embryos is related to maternal size. Size at birth is approximately 25 to 30 cm TL. Gestation time and reproductive periodicity unknown. In the area of the Tucuruí reservoir it breeds year-round, probably due to the artificial water level control inside the reservoir.|
|Use and Trade:||Aquarium trade|
|Major Threat(s):||Persecution occurs along the sandy beaches in some parts of its range in summer or during the dry season (July and August), however there are no estimates available for the numbers of this species killed. This species is exported for the ornamental trade as P. motoro, officially from Manaus and illegally from Belém. Legal ornamental fishing of this species was recently approved on the grounds that scientific research is also carried out in order to provide sustainable levels. Habitat degradation caused by illegal mining activities is likely to be indirectly impacting this species.|
|Conservation Actions:||No conservation measures are in place for this species. Monitoring of the unregulated ornamental fish trade, policing of the illegal trade, and education to limit persecution are essential. Although the population has not been negatively affected by the Tucuruí Dam, it is important to estimate the impact of a series of dams along the Tocantins river.|
|Citation:||Rincon, G. (SSG South America Regional Workshop, June 2003) 2004. Potamotrygon henlei. The IUCN Red List of Threatened Species. Version 2014.2. <www.iucnredlist.org>. Downloaded on 29 August 2014.|