卡氏江魟 · Large Spot Stingray

Overview

A large South American freshwater ray also traded as P53, Potamotrygon falkneri requires substantial floor space and a complete support system. Heavy feeding, waste management, and the venomous tail spine are central to care, not secondary considerations.

Distribution & habitat

It is native to the Paraná and Paraguay basins in Brazil, Paraguay, and Argentina. Genus-level habitat accounts include sandbanks, river shallows, muddy tributaries, flooded forest, and lakes or ponds left by receding floods.

Aquarium setup

Use at least the suggested 180 by 60 by 90 cm, preserving as much open floor as possible. Secure large decor and keep lighting restrained. Fine river sand allows burial; a bare floor simplifies cleaning but removes that refuge. Plants may be damaged even when attached to decor.

Large biological filtration and disciplined upkeep are essential. A sump keeps heaters out of reach and reduces contact burns; canisters must also be adequately sized. Suggested circulation is around four tank volumes per hour with surface agitation for oxygen. Weekly changes up to half the volume and a close-fitting cover address waste and surface feeding activity.

Diet & feeding

Freshwater-ray feeding guidance uses varied animal foods such as appropriate fish, shrimp, shellfish, squid, and earthworms, with smaller live or frozen items for juveniles. At least two daily meals are suggested for these active feeders.

Thin new imports may initially refuse frozen food. Establish feeding promptly with suitable live worms if needed, then gradually transition once condition improves. Avoid mammalian or avian meats and routine feeder fish.

Behaviour & compatibility

Choose peaceful companions beyond swallowing size, preferably using upper water. Aggressive territorial fish can undermine ray health. Suckermouth catfish may attach to and injure the disc, so algae-feeding habits do not establish safety. Different river-ray species may hybridize and should be separated when breeding is intended.

Sexual dimorphism

Males have a backward-projecting clasper on the inner side of each pelvic fin. These are smaller but still visible in young males.

Breeding

Trials can draw on the genus pattern of internal fertilization and maternal nourishment, without treating it as a proven captive method for this species. Related rays supplement yolk with uterine secretions. Pair compatibility is uncertain; a well-conditioned female larger than the male is preferable.

Courtship chasing and disc biting may cause injury, so separation facilities are essential. Related-ray practice includes increased food for pregnant females, separate care for newborns, and frequent small meals after yolk absorption. Rest periods between repeated litters protect the female.

Notes

The barbed tail spine can cause severe pain and tissue injury. Avoid handling or netting; use an appropriate solid container or large fish bag for transfer. Shed spines remain hazardous for a time, and stings require medical attention. Before purchase, check active feeding and body condition. Sunken head areas, prominent pelvic structures, or persistently curled disc margins are warning signs.