Iridescent Shark Identification Guide

Key identification features

• Shark-like body silhouette with a tall, triangular dorsal fin
• Silvery-grey, scaleless skin with an iridescent sheen
• Two pairs of short barbels near the mouth
• Dark stripe along the lateral line in juveniles, which fades and becomes less distinct with age
• Deeply forked caudal fin
• Grows large, often exceeding 1 m in ponds, lakes, or spacious aquariums

Common look-alikes

• Mekong giant catfish: a close relative but lacks the lateral stripe, has a humped back, and grows far larger with barbels that are much shorter or nearly absent.
• True sharks: unrelated cartilaginous fish that live only in marine or brackish water and have visible gill slits, unlike this freshwater bony fish.

Where you'll see one

Iridescent sharks are native to the Mekong and Chao Phraya river basins of Southeast Asia, where they inhabit large rivers and associated floodplain lakes. They are also widely farmed for aquaculture and kept in large public aquariums and ponds well outside their native range.