Phyllobates Lugubris is somewhat small, males reach 21 mm (7/8 inch), females reach 24 mm (1 inch).

They have a black background color, though the mottling on the limbs is yellowish-green.

Phyllobates Lugubris inhabits the Caribbean lowlands of Costa Rica and

Panama, from sea level to 650 meters (2,150 ft). Poison dart frogs of the genus Phyllobates are among the most toxic frogs known.

Although both Costa Rican species are not as dangerously poisonous as some of their South American relatives, you should always wash your hands after handling these frogs.