Basal Cyclorrhapha In Amber From The Cretaceous And Tertiary (Insecta: Diptera), And Their Relationships: Brachycera In Cretaceous Amber Part Ix David A. Grimaldi Author Grimaldi, David A. Division of Invertebrate Zoology American Museum of Natural History, New York text Bulletin of the American Museum of Natural History 2018 2018-10-24 2018 423 1 97 http://www.bioone.org/doi/10.1206/0003-0090-423.1.1 journal article 7631 10.1206/0003-0090-423.1.1 2e886aea-b59a-45a6-aeaa-2427d584a894 0003-0090 4613008 Aschizomyia , new genus DIAGNOSIS: Head lacking macrosetae, female frons pubescent; ptilinal suture absent; basal flagellomere large, tapered asymmetrically to apical point (which bears arista); scutum with numerous scattered setulae (none in rows); thorax with one pair of dorsocentral setae, one pair of of scutellars, three postalars, four notopleurals, no supraalars. Vein Sc long; apices of R 4+5 and M 1 converge closely at wing tip but do not meet; M forked, with very short stem; cells dm and cup very large. Metatibia with ventral pair short, stout apical spurs. TYPE SPECIES : A. burmensis , n. sp. ETYMOLOGY: Derived directly from Aschiza, and - myia (Greek, “fly”). The genus name is feminine. COMMENTS: The phylogenetic position of the genus is equivocal (fig. 51), having features of Syrphidae and Pipunculidae but decidedly more primitive than the crown group of either. Syrphid features include a short sc-r crossvein, apex of CuA 1 incomplete, the exposed female frons being pubescent (the head lacking any macrosetae), and the alula is well developed. Aschizomyia plesiomorphically has a small cell bm; C ends at the apex of M 1 (instead of R 4+5 ); M is forked, and M 1 does not join R 4+5 preapically. The venation is very similar to that of Protonephrocerus , but Aschizomyia lacks all the features of the head, female terminalia, and pretarsi that characterize Pipunculidae . The large cup cell occurs in both Syrphidae and Pipunculidae , possibly convergently. It is difficult to discern whether the arista is dorsally or apically situated on the basal flagellomere, since it occurs at the apex of a narrow, pointed lobe and the flagellomere is asymmetrical, with an extensive, emarginate ventral margin. I have chosen to depict Aschizomyia , preliminarily, in a basal trichotomy with Syrphidae and Pipunculidae + Schizophora because of the equivocal morphological evidence. The lack of a ptilinum indicates that Aschizomyia is not a schizophoran, though the possibility remains that it is a stem-group one.