Phoomyia, a new genus of Dolichopodinae from the Oriental Region (Diptera: Dolichopodidae).

Phoomyia Naglis & Grootaert gen. nov. is described to include two new species of beach-dwelling dolichopodine flies from coastal Sri Lanka and Thailand: Phoontyia srilankensis Naglis & Brooks sp. nov. and Phoomnyia thailandensis Naglis & Grootaert sp. nov. The new genus is closely related to the genera Argyrochlamys Lamb and Pseudargyrochlamys Grichanov, and is distinguished based on characters of the hind leg, and features of the male and female terminalia. Adults of Phoomyia are found on sandy coastal beaches often near the burrows of ghost crabs.

Revision of the Empis subgenus Enoplempis Bigot, east of the Rocky Mountains (Diptera: Empididae).

The Empis subgenus Enoplempis Bigot, east of the Rocky Mountains of North America is revised. A total of 19 species are recorded from this region including seven new species: E. (En.) amytis Walker, E. (En.) appalachicola Sinclair sp. nov., E. (En.) arthritica Melander, E. (En.) ctenonema Melander, E. (En.) enodis Melander, E. (En.) gladiator Melander, E. (En.) gulosa Coquillett, E. (En.) loripedis Coquillett, E. (En.) montywoodi Brooks sp. nov., E. (En.) nodipoplitea Steyskal, E. (En.) nuda Loew, E. (En.) pectinata Sinclair sp. nov., E. (En.) penicillata Brooks sp. nov., E. (En.) prodigiosa Cumming sp. nov., E. (En.) snoddyi Steyskal, E. (En.) stenoptera Loew, E. (En.) tridentata Coquillett, E. (En.) vockerothi Cumming sp. nov., E. (En.) volsella Sinclair sp. nov. The following new synonymies are designated: E. (En.) longipes Loew, E. (En.) longeoblita Steyskal, E. (En.) deterra Walley = E. (En.) amytis; E. (En.) cacuminifer Melander = E. (En.) gulosa. Lectotypes are designated for the following species: E. (En.) arthritica, E. (En.) cacuminifer, E. (En.) ctenonema, E. (En.) enodis, E. (En.) gladiator, E. (En.) loripedis, E. (En.) stenoptera and E. (En.) tridentata. A key to eastern species is presented and distributions illustrated. The form of nuptial gift presentation displayed within this group, including the use of balloons (with or without prey) and unwrapped prey are indicated for species when known.

The first Neotropical and Afrotropical species of Microphorella Becker, with a key to the genera of Parathalassiinae and species of Microphorella from the Southern Hemisphere (Diptera: Dolichopodidae sensu lato).

Two new species of Microphorella Becker are described and illustrated from Chile and South Africa, respectively: M. amorimi sp. nov. (Maule Region) and M. irwini sp. nov. (Western Cape Province), representing the first formal records of the genus from the Neotropical and Afrotropical Regions. In addition, a key to the genera of Parathalassiinae and species of Microphorella from the Southern Hemisphere is also provided.

Revision of the Nearctic Microphorinae (Diptera: Dolichopodidae sensu lato).

The Nearctic species of the dolichopodid subfamily Microphorinae are revised. Two genera and 33 species are recognized including five species of Microphor Macquart and 28 species of Schistostoma Becker. Both genera are redefined, redescribed and diagnosed, a key to the genera and species in the Nearctic Region is provided, the known geographical distribution of each species is mapped and ecological information is summarized. In addition to the three previously known species of Nearctic Schistostoma, i.e., S. armipes (Melander), S. sycophantor (Melander) and S. yakimense (Melander), the Nearctic fauna includes eight species newly transferred from Microphor as well as 17 new species. These species of Schistostoma are classified into four species groups as follows: the S. atratum species group including S. atratum (Coquillett, 1900) comb. nov., S. borkenti sp. nov., S. chloeae sp. nov. and S. lillyae sp. nov.; the S. isommatum species group including S. caroleae sp. nov., S. evisceratum (Melander, 1940b) comb. nov., S. fitzgeraldi sp. nov., S. isommatum (Melander, 1928) comb. nov., S. powelli sp. nov., S. shamshevi sp. nov., S. sinclairi sp. nov., S. susanae sp. nov. and S. tacomae (Melander, 1940b) comb. nov.; the S. ravidum species group including S. armipes (Melander, 1928), S. arnaudi sp. nov., S. cirripes (Melander, 1940b) comb. nov., S. heatherae sp. nov., S. longistylum sp. nov., S. michaeli sp. nov., S. oharai sp. nov., S. ravidum (Coquillett, 1895) comb. nov., S. robustum (Melander, 1928) comb. nov., S. rudei sp. nov., S. strigilifer (Melander, 1940b) comb. nov. and S. sycophantor (Melander, 1902); and the S. yakimense species group including S. pecki sp. nov., S. runyoni sp. nov. and S. yakimense (Melander, 1928). Schistostoma ravum (Melander, 1940b) comb. nov. is also transferred from Microphor and is newly synonymized with S. evisceratum (Melander, 1940b), syn. nov. The Nearctic members of Microphor now comprise only three of the previously known species, plus two new species. These five species are classified into two species groups as follows: the M. discalis species group including M. discalis Melander, 1940b, M. skevingtoni sp. nov. and M. turneri sp. nov.; and the M. obscurus species group including M. bilineatus (Melander, 1902) and M. obscurus Coquillett, 1903. Lectotype designations are made for Holoclera bilineata Melander, Microphorus armipes Melander, Microphorus ravidus Coquillett, Microphorus strigilifer Melander and Holoclera sycophantor Melander.

New Australasian Parathalassiinae (Diptera: Dolichopodidae sensu lato).

One species of Chimerothalassius Shamshev & Grootaert, namely C. marshalli sp. nov. is described from New Zealand, and two other species, namely C. riparius sp. nov. and C. sinclairi sp. nov. are described from New Caledonia. Two species of Microphorella Becker, namely M. bungle sp. nov. and M. viticula sp. nov., are described from Australia. These new parathalassiine descriptions increase the Australasian species diversity of Chimerothalassius and Microphorella to four species each. In addition, the genus Eothalassius Shamshev & Grootaert is recorded from New Caledonia based on a single female, and the male genitalia of the Australian species M. iota Colless is newly illustrated. A key to the genera and species of male Parathalassiinae in the Australasian Region is also provided.

Establishment of the Microphorella breviradia species group, with a key to the Nearctic species groups of Microphorella Becker (Diptera: Dolichopodidae sensu lato: Parathalassiinae).

The Microphorella breviradia species group is established for three new species from western North America, namely Microphorella breviradia sp. nov., M. macdonaldi sp. nov. and M. vespera sp. nov., including an identification key to species. COI mitochondrial DNA barcode sequences were obtained for two of the three species and possibly suggest the existence of additional cryptic species. The phylogenetic relationships of the Microphorella breviradia species group to the remainder of the Microphorella species groups are reviewed on a worldwide basis. A key to the four known Nearctic species groups of Microphorella is also provided.

Revision of the Empis (Enoplempis) mira species group (Diptera: Empididae).

The Empis (Enoplempis) mira species group is revised and includes the type species of Enoplempis and four new species (E. macdonaldi sp. nov., E. submira sp. nov., E. williamturneri sp. nov., E. winkleri sp. nov.). A lectotype is designated for Enoplempis mira Bigot. The species group is defined by the yellow body colour, directionally asymmetrical male hindlegs and geniculate hindlegs in both males and females. The group has not been found outside of western North America and is known from California, Oregon, Idaho and Washington.

A new species of Philetus Melander (Diptera: Empididae) from the Yukon Territory, Canada.

The Nearctic genus Philetus Melander, 1928 is a rarely collected group of empidid flies that contains two western species, namely P. memorandus Melander and P. schizophorus Melander. The genus was fully diagnosed by Cumming et al. (2016) with both known species redescribed and their distributions mapped. Here we describe a third species of Philetus from a single male collected recently in the Richardson Mountains of the Yukon Territory in Canada and provide a key to species based on male morphology. Terms used for adult structures follow those of Cumming Wood (2017) and methods follow those outlined in Cumming et al. (2016).

Phylogenetic analysis and preliminary classification of the Parathalassiinae (Diptera: Empidoidea: Dolichopodidae sensu lato).

Phylogenetic relationships of the subgroups of Parathalassiinae are presented, based on a morphological cladistic analysis. Worldwide, all known extant genera, species groups and newly discovered undescribed lineages are represented in the analysis. Some previously proposed generic relationships are supported by the analysis, but recognition of many current genera renders the present concept of Microphorella Becker as both paraphyletic and polyphyletic. Microphorella merzi Gatt is here classified in Eothalassius Shamshev Grootaert, as Eothalassius merzi (Gatt) comb. nov. A preliminary classification with all included extant lineages within the Parathalassiinae (at the genus and species group level) is outlined. The ranking of these lineages is discussed and several species groups of Microphorella may need to be elevated to generic or subgeneric level, whereas some currently recognized genera may need to be relegated to subgenera.

Remarkable new fossil species of Schistostoma Becker (Diptera: Dolichopodidae: Microphorinae) from mid-Cretaceous Burmese amber.

Two closely related and distinctive species of Schistostoma Becker, i.e. Schistostoma burmanicum sp. nov. and Schistostoma foliatum sp. nov., are described from two male specimens preserved in mid-Cretaceous Burmese amber and recorded as the first known fossil representatives of this extant genus of Microphorinae. Both species possess greatly enlarged lamellate fore tibiae and modified leg chaetotaxy that are presumably male secondary sexual features. The generic limits of Schistostoma are briefly discussed and a rationale for the inclusion of these new species is provided.

Revision of the Holarctic genus Gloma Meigen (Diptera: Empidoidea: Brachystomatidae: Trichopezinae).

The Holarctic genus Gloma Meigen is revised and includes five species (G. fuscipennis Meigen, G. fuscipes Melander, G. luctuosa Melander, G. pectinipes Melander, G. pyricornis Saigusa Sinclair sp. nov.) and two undescribed species from China, presently known only from females. The monotypic Baltic amber genus Palaeoparamesia Meunier is discussed as possibly congeneric with Gloma. The Baltic amber species Gloma hirta Loew is considered a nomen dubium. A lectotype is designated for Gloma luctuosa. All species are described or diagnosed, and their geographic distributions mapped. A World key to the species of Gloma is provided. Phylogenetic placement of the genus, including a possible new relationship with Oreogeton Schiner is considered, and the relationships and zoogeographic history of the species are discussed based on a morphological cladistic analysis.

New species of Chimerothalassius Shamshev Grootaert (Diptera: Dolichopodidae: Parathalassiinae) from the West Indies and Costa Rica.

Chimerothalassius runyoni sp. nov. is described from rocky coastlines of Montserrat and Dominica, and the genus is newly recorded from the Pacific coast of Costa Rica, based on female specimens of an undescribed species.

New species and records of Cheiromyia Dyte from Brazil and French Guiana (Diptera: Dolichopodidae).

Cheiromyia carolina Limeira-de-Oliveira Brooks sp. nov. and C. nordestina Limeira-de-Oliveira Cumming sp. nov. are described from Brazil, and C. fuscipennis Pollet Brooks sp. nov. is described from the Mitaraka Mountains in southwestern French Guiana. New distribution records are reported for C. brevitarsis Brooks, C. palmaticornis (Parent) and C. pennaticornis (Parent), and a revised key to males of the eight known species of Cheiromyia Dyte, 1980 is provided. The female of C. pennaticornis is also described for the first time.

Diversity of saproxylic dance flies and long-legged flies (Diptera: Empidoidea) in a temperate deciduous forest in Quebec, Canada.

A large diversity of saproxylic Empidoidea from a temperate deciduous forest in southern Quebec is documented. Adults of 43 empidoid species representing 19 genera in 12 subfamilies and three families were collected from in situ sealed emergence traps placed over decayed logs of American beech (Fagus grandifolia Ehrhart) and sugar maple (Acer saccharum Marshall). The results of this technique give a clear indication of the saproxylic larval and pupal habitat of these species. The importance of Empidoidea as larval predators in decayed wood niches is noted.

Comprehensive inventory of true flies (Diptera) at a tropical site.

Estimations of tropical insect diversity generally suffer from lack of known groups or faunas against which extrapolations can be made, and have seriously underestimated the diversity of some taxa. Here we report the intensive inventory of a four-hectare tropical cloud forest in Costa Rica for one year, which yielded 4332 species of Diptera, providing the first verifiable basis for diversity of a major group of insects at a single site in the tropics. In total 73 families were present, all of which were studied to the species level, providing potentially complete coverage of all families of the order likely to be present at the site. Even so, extrapolations based on our data indicate that with further sampling, the actual total for the site could be closer to 8000 species. Efforts to completely sample a site, although resource-intensive and time-consuming, are needed to better ground estimations of world biodiversity based on limited sampling.

Remarkable fly (Diptera) diversity in a patch of Costa Rican cloud forest: Why inventory is a vital science.

Study of all flies (Diptera) collected for one year from a four-hectare (150 x 266 meter) patch of cloud forest at 1,600 meters above sea level at Zurquí de Moravia, San José Province, Costa Rica (hereafter referred to as Zurquí), revealed an astounding 4,332 species. This amounts to more than half the number of named species of flies for all of Central America. Specimens were collected with two Malaise traps running continuously and with a wide array of supplementary collecting methods for three days of each month. All morphospecies from all 73 families recorded were fully curated by technicians before submission to an international team of 59 taxonomic experts for identification.        Overall, a Malaise trap on the forest edge captured 1,988 species or 51% of all collected dipteran taxa (other than of Phoridae, subsampled only from this and one other Malaise trap). A Malaise trap in the forest sampled 906 species. Of other sampling methods, the combination of four other Malaise traps and an intercept trap, aerial/hand collecting, 10 emergence traps, and four CDC light traps added the greatest number of species to our inventory. This complement of sampling methods was an effective combination for retrieving substantial numbers of species of Diptera. Comparison of select sampling methods (considering 3,487 species of non-phorid Diptera) provided further details regarding how many species were sampled by various methods.        Comparison of species numbers from each of two permanent Malaise traps from Zurquí with those of single Malaise traps at each of Tapantí and Las Alturas, 40 and 180 km distant from Zurquí respectively, suggested significant species turnover. Comparison of the greater number of species collected in all traps from Zurquí did not markedly change the degree of similarity between the three sites, although the actual number of species shared did increase.        Comparisons of the total number of named and unnamed species of Diptera from four hectares at Zurquí is equivalent to 51% of all flies named from Central America, greater than all the named fly fauna of Colombia, equivalent to 14% of named Neotropical species and equal to about 2.7% of all named Diptera worldwide. Clearly the number of species of Diptera in tropical regions has been severely underestimated and the actual number may surpass the number of species of Coleoptera.        Various published extrapolations from limited data to estimate total numbers of species of larger taxonomic categories (e.g., Hexapoda, Arthropoda, Eukaryota, etc.) are highly questionable, and certainly will remain uncertain until we have more exhaustive surveys of all and diverse taxa (like Diptera) from multiple tropical sites.        Morphological characterization of species in inventories provides identifications placed in the context of taxonomy, phylogeny, form, and ecology. DNA barcoding species is a valuable tool to estimate species numbers but used alone fails to provide a broader context for the species identified.

Neothalassius, a new genus of Parathalassiinae (Diptera: Dolichopodidae s.lat.) from the Pacific coast of South America.

A new genus, Neothalassius gen. nov., and two new species, Neothalassius triton sp. nov. and Neothalassius villosus sp. nov., are described from rocky shorelines along the Pacific seacoast of South America. The phylogenetic placement of Neothalassius within the subfamily Parathalassiinae is discussed.

Review of the little-known western Nearctic fly genus Philetus Melander (Diptera: Empididae), with a discussion of its phylogenetic assignment.

The western North American empidid genus Philetus Melander is reviewed, including redescription of the two included species, P. memorandus Melander and P. schizophorus Melander. A lectotype is designated for P. schizophorus. The        distributions of both species are mapped and the male terminalia are illustrated. The female of P. schizophorus is discovered for the first time through comparison of COI mitochondrial DNA barcode sequences. The phylogenetic assignment of  Philetus within the Empididae is discussed based on a reinterpretation of male terminalia homologies.

Gondwanamyia, a new empidoid (Diptera) genus of uncertain placement.

A new minute-size empidoid fly genus, Gondwanamyiagen. n. and two new species (Gondwanamyia chilensis Cumming & Saigusa, sp. n., Gondwanamyia zealandica Sinclair & Brooks, sp. n.) are described, illustrated, and their distributions mapped. The family and subfamily assignments remain uncertain, but features of the female terminalia potentially suggest Trichopezinae (Brachystomatidae).