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. 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 to signal their venomous skin to potential predators, helping these frogs escape danger. They are small, although bigger than the Strawberry ones. 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 venomous it probably is. Care has to be taken when handling venomous frogs, as contact with sensible parts of the human body can produce very unpleasant sensations.
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 venomous species like this one are more active during the day. I was also afraid of accidentally touching them, so I kept my distance.