Rubber Eel

The rubber eel is a fully aquatic caecilian, family Typhlonectidae, native to rivers and wetlands of Colombia and Venezuela, with a dark, smooth, limbless body that gives it its common name despite being an amphibian rather than a fish. It breathes mostly through its skin, supplementing this by surfacing occasionally for air, and gives birth to a small number of fully developed young after a gestation of several months rather than laying eggs.