Kronichthys subteres is a species of armored catfish endemic to Brazil where it occurs in the Ribeira de Iguape River basin.

Kronichthys subteres inhabits streams with rocky and sandy bottom.

They occasionally take chironomid and simuliid larvae, as well as tiny crustaceans.

When grazing algae off the substrate, the fish makes vigorous mouth movements, and moves by jerky movements probably related to its mouth making alternate grazing and attaching to the substrate.

K. subteres leaves conspicuous grazing marks on exposed rocks.