Larvae of the neotropical frog family Centrolenidae live hidden on the bottom of rivers between stones, gravel, and leaf litter. Their lotic fossorial behavior makes it impossible to find and study these tadpoles in their natural environment. Therefore, presently only poor reports and descriptions of them are available in the literature. In the present study all known 13 Costa Rican centrolenid species (or taxa) were reared under laboratory conditions. Their live tadpoles are described in different stages of their development. Six of the 13 descriptions are new (Cochranella euknemos, Sachatamia albomaculata, Sachatamia ilex, Hyalinobatrachium chirripoi, Hyalinobatrachium talamancae and Hyalinobatrachium vireovittatum). A species key and detailed diagnostic descriptions with abundant illustrations allow the identification of tadpoles of the thirteen species.