Abstract 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, Ngo-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.

中文翻译：

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来自中白垩世缅甸琥珀的新 Alavesia 物种突出了生殖器结构同源性（双翅目：Empidoidea：Atelestidae）

摘要 Alavesia Waters 和 Arillo 的一个新种，1999，即 A. longistylata Zhang 和 Wang，sp。nov.，是从白垩纪中期的缅甸（缅甸）琥珀中描述的。同时，A. myanmarensis Jouault、Ngo-Muller 和 Nel, 2020 的雌性生殖器在新材料的基础上进行了补充，可以进一步与现存物种进行比较。结果表明，Alavesia 的雄性和雌性终端在化石和现存物种之间表现出高度的结构同源性，意味着该属的形态保护时期很长。