Five new species of Macrostomus Wiedemann and a checklist of Empididae (s. str.) (Diptera) from Bolivia.

Ten Bolivian species of Macrostomus Wiedemann were studied. Five species are redescribed based on type specimens           described by Bezzi. The species are included in the following species-groups: four in the M. ferrugineus species-group: M.       arcucinctus (Bezzi), M. argyrotarsis (Bezzi), M. dolichopterus (Bezzi) and M. grallatrix (Bezzi); three in the M. limbipennis species-group: M. macerrimus (Bezzi), M. montanus sp. nov. and M. rodriguezi sp. nov.; one species in the M. amazonensis species-group: M. falcatus sp. nov.; and two unplaced to species-group: M. trifidus sp. nov. and M. trilineatus sp. nov. A key to the 12 species of Macrostomus found in Bolivia, including M. limbipennis (Bezzi) and M. pictipennis (Bezzi), is presented. Macrostomus argyrotarsis (Bezzi) is also recorded for the first time from Peru. A checklist of 31 described species of Bolivian Empididae s. str. is included. Three empidid species originally described from Mexico that had previously been recorded from Bolivia, are excluded from the Bolivian fauna.

Where do the Neotropical Empidini lineages (Diptera: Empididae: Empidinae) fit in a worldwide context?

The tribe Empidini (Diptera: Empididae: Empidinae) is a diverse group with fourteen genera, seven of which are exclusive to the Neotropical region: Bolrhamphomyia Rafael, Chilerhamphomyia Rafael, Hystrichonotus Collin, Lamprempis Wheeler and Melander, Macrostomus Wiedemann, Opeatocerata Melander and Porphyrochroa Melander. Although Empidini itself is likely paraphyletic, many presumably monophyletic genera and species groups are recognized. Here, we apply DNA sequences from multiple genes to infer the phylogeny of Empidini, focusing on placing the Neotropical lineages within the entire tribe and identifying monophyletic groups. We included 98 Empidini taxa along with 18 outgrous terminals, spanning the diversity within the group. The results from the analyses performed are largely similar, with major groupings of genera in common. Specifically, the analyses recovered a monophyletic Hilarini and a paraphyletic Empidini. Most species from Chile and Argentina (Andean region) are found to belong to an early branching lineage within Empidinae, and are not monophyletic with other Empidini. A large portion of the remaining Neotropical Empidini (not Andean) comprises a single clade that includes four endemic genera and a number of Neotropical Empis Linneaus species. Macrostomus and Porphyrochroa each recovered as monophyletic and sister to one another, although generic placement of a few taxa remains uncertain due to conflicting morphological features. Lamprempis+Opeatocerata are also found to be sister-taxa in most analyses. Several large genera were found to be polyphyletic or paraphyletic including Empis and Rhamphomyia Meigen. We evaluate our findings and discuss them in light of current Empidinae taxonomy.