The second species of Acartophthalmites from Baltic amber (Eocene), with notes on the relationships of the genus (Diptera: Acalyptrata)

Abstract: Hitherto, the Paleogene fossil genus Acartophthalmites Hennig, 1965 included only the type species, A. tertiaria Hennig, 1965, from Baltic amber (Eocene, ca. 40 Mya). An additional species, Acartophthalmites clusioides sp. nov., is described based on a well preserved male in a Baltic amber inclusion from Kaliningrad: Yantarny (Russia). It distinctly differs from A. tertiaria in a number of characters demonstrating that the genus Acartophthalmites is morphologically more diverse than considered previously. Moreover, the study of A. clusioides resulted in finding that Acartophthalmites is obviously not related to Acartophthalmidae (where it was originally affiliated), but seems to be closer to Clusiidae, although surely not belonging to the latter family as currently delimited. Therefore a revision of all available specimens of Acartophthalmites is suggested to gain a more complete set of morphological data of this genus, enabling analysis of its phylogenetic relationships.

Key words: Diptera, taxonomy, Acartophthalmites, A. clusioides sp. nov., Baltic amber, Eocene, relationships