The Green and Black Poison Dart Frog is one of the species in this family that occurs in Costa Rica, along with the Strawberry Poison Dart Frog and other species, although this species is bigger than the Strawberry. Poison Dart Frogs are diurnal, so it is relatively common to flush them from the floor litter during hiking trips through forested areas. Their contrasting body color is an adaptation meant to signal their poisonous skin to potential predators, helping these frogs escape from danger. Poison Dart Frogs are known because of their ability to withstand ant venom and convert it into their own which means the older the frog, the more poisonous it becomes. Some of these species were used by aboriginal people in South America to kill monkeys and other prey, by rubbing their skin to the arrows that they shoot.
It is normal to see Poison Dart Frogs resting on the leaves of bromeliads, where they usually deposit their larvae, which will develop inside a water pool in the base of a bromeliad leaf. They are more conspicuous when seen on leaf litter, which usually turns brown as the vegetation decays. Also poisonous species like this one are more active during the day. The two times I have had the opportunity to photograph this species, I was careful to keep my distance, as they jumped around quickly and could touch me at any moment. While being touched generally won´t produce any reaction, being careless afterwards and bringing the hands to touch the eyes or the nose after having grabbed one of these can produce significant effects, up to partial blindness.