Iridescent Shark

Physical Characteristics

Body is laterally compressed with a shark-like silhouette. They feature a dark grey to bluish-black dorsal side with a silver, iridescent sheen along the flanks, which fades as they mature. They have a small adipose fin, a deeply forked caudal fin, and large eyes positioned low on the head.

Habitat & Distribution

Native to the Mekong and Chao Phraya river basins in Southeast Asia. They inhabit deep pools in large rivers and move into flooded jungles during the rainy season. They prefer tropical, slow-moving or standing water.

Size & Weight

In the wild, they can grow up to 130 cm (4.3 feet) in length and weigh up to 44 kg (97 lbs). In home aquaria, they often reach 60-90 cm if given adequate space.

Similar Looking Species

Mekong Giant Catfish (Pangasianodon gigas), which is larger and lacks teeth as an adult; and the High-fin Shark Catfish (Pangasius sanitwongsei), which has elongated filaments on its dorsal and pectoral fins.

Ecological Role

Omnivorous scavengers that feed on crustaceans, other fish, and plant matter. They play a key role in nutrient cycling within their river systems. The species is currently listed as Endangered by the IUCN due to overfishing and habitat degradation/fragmentation from dam construction.

Identified on: 1/3/2026

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