Occurs in principal river beds, in upstream parts of rivers, downstream rapids, in backwater zones or on stony bottoms of pools with dead tree trunks. Active at dusk. Piscivorous. Emits loud grumblings (Ref. 35381). Secretes toxic mucus and the wounds caused by its pectoral spines are very painful. The female can preserve spermatozoids by coating them with original maternal secretions and inserting them in the epithelium of its genital tract (Ref. 27188). The presence of sperm in the mucus of the female's genital tract is indicative of internal fertilization (Ref. 35381).
South America: Amazon, Corantijn, Essequibo, Orinoco, and Paraná River basins; also in major rivers of the Guianas.
Widespread in South America.