New species of Ablabesmyia Johannsen from the Neotropical region: first report of a sponge-dwelling Tanypodinae

The larva, pupa and male of a new Neotropical chironomid species, Ablabesmyia tucuxi Neubern et Fusari sp. n., are de-scribed and illustrated. The larvae were found in freshwater sponge colonies of Drulia uruguayensis Bonetto et Ezcurrade Drago, 1968 and Oncosclera spinifera (Bonetto et Ezcurra de Drago, 1973) in Brazilian savanna streams. The morpho-logical characteristics of the larval head and the presence of fine particles in the larval gut contents suggest that the larvae probably feed on the sponge tissue or on other animals that live inside the sponges.