Abstract
The morphological and ultrastructural descriptions of the larvae of two cave species of Trechini-Duvalius (Hungarotrechus) subterraneus (L. Miller, 1868) and Duvalius (Biharotrechus) paroecus (J. Frivaldszkyi, 1865)-are presented in this paper. The interest in studying these larvae lays in their rarity and the limited distribution of the Duvalius species. The larvae were collected from caves in the Romanian Carpathians and were examined under a stereomicroscope and scanning electron microscopy. New important taxonomical and fine morphological characteristics are discussed together with conclusions on the larvae microhabitat as part of the measures to be taken by a proper management of caves.