[BigV]

in wikipedia:

This success of this species is due to its specialized predation on the abundant Antarctic krill of the Southern Ocean, for which it has uniquely adapted, sieve-like tooth structure. Indeed, its scientific name, translated as "lobe-toothed (lobodon) crab eater (carcinophagus)", refers specifically to the finely lobed teeth adapted to filtering their small crustacean prey.[3] Despite its name, crabeater seals do not eat crabs. As well as being an important krill predator, the crabeater seal is an important component of the diet of leopard seals (Hydrurga leptonyx), which consume about 80% of all crabeater pups.