New Alavesia species from mid-Cretaceous Burmese amber highlight genitalic structural homology (Diptera: Empidoidea: Atelestidae)

A new species of Alavesia Waters and Arillo, 1999, namely A. longistylata Zhang and Wang, sp. nov., is described from mid-Cretaceous Burmese (Myanmar) amber. Meanwhile, the female genitalia of A. myanmarensis Jouault, Ngô-Muller and Nel, 2020 is supplemented based on new material, which allows a further comparison with the extant species. The results indicate that the male and female terminalia of Alavesia show high structural homology among fossil and extant species, implying a great period of morphological conservation in this genus.