Diversity of the Fossil Genus Palaeoglaesum Wagner (Diptera, Psychodidae) in the Upper Cretaceous Amber of Myanmar.

Abstract

Simple SummaryBruchomyiinae is one of seven subfamilies of Psychodidae. In the contemporary fauna, this small, relict subfamily occurs mainly in tropical and sub-tropical regions. Examination of inclusions preserved in the Upper Cretaceous amber of Myanmar (also known as Burmese amber), which is almost 100 mya, shows that this subfamily was abundant during the Cretaceous period. The extinct genus Palaeoglaesum is known only from this fossil resin. Moreover, its numerous inclusions and high diversification confirm that the Mesozoic was the stage of the early evolution and radiation of Psychodidae. Here we describe three new species and we provide additional details regarding the morphology of fossil species.Cretaceous Myanmar amber is abundant in inclusions belonging to the genus Palaeoglaesum. In addition, a significant morphological diversity among representatives of Palaeoglaesum can be observed. However, none of its representatives have been found in other fossil materials. Herein three new species: P. stebneri sp. nov., Skibińska and Krzemiński P. teres sp. nov. Skibińska and Albrycht, and P. pilosus sp. nov. Skibińska, Krzemiński and Zhang from Cretaceous Myanmar amber are described and illustrated. The very small size and characters of male hypopygium with aedeagus strongly bent and apically forked are pertinent to diagnosing the genus and species. New materials show that this genus and the whole subfamily Bruchomyiinae were probably more abundant and more diverse than the presently known extant fauna.