Coquí Común (Eleutherodactylus Coquí) The Eleutherodactylus coquí, or coquí común, is the most common species of coquí on the island of Puerto Rico. They are considered common because this species can be found throughout the island's varying ecological zones. These tiny tree frogs (measuring from 16-20 mm; 5/8hs to 1/16ths of an inch), can be found resting in tall grasses, under the bark of trees, in axilas of palms, bromeliads, and under rocks or tree trunks. It is not far fetched to also find coquí scaling the walls of buildings and houses or underneath loose trash or manmade objects.