Molecular evidence suggests that in spite of the great morphological diversity seen throughout the order, all catfish form a monophyletic group. Catfish belong to a superorder called the Ostariophysi, which also includ… See more

Extant catfish species live inland or in coastal waters of every continent except Antarctica. Catfish have inhabited all continents at one time or another. They are most diverse in tropical South America, Asia, and Africa, … See more

Most catfish are bottom feeders. In general, they are negatively buoyant, which means that they usually sink rather than float due to a reduced gas bladder and a heavy, bony head. Catfish have a variety of body shapes, tho… See more