Seven new species of Hydroptila (Trichoptera: Hydroptilidae) from Costa Rica are described: H. carara, H. maritza, H. osa, H. paradenza, H. maza, H. rastrilla, H. singri, and one from Panama, H. nusagandia. Ten additional species occurring in Costa Rica are recorded: H. brailovskyi Bueno-Soria, H. constricta Bueno-Soria, H. curvata Bueno-Soria, H. flinti Bueno-Soria, H. icona Mosely, H. meralda Mosely, H. mexicana Mosely, H. misolha Bueno-Soria, H. paschia Mosely, and H. veracruzensis Flint. In addition, illustrations of H. denza Ross and H. grenadensis Flint are included to help clarify the taxonomy of the denza species group. Finally, an illustrated key is provided for males of all species occurring in lower Central America.
- Costa Rica