A new monotypic genus of Dactylomyiini (Diptera: Dolichopodidae: Neurigoninae) from the Brazilian Chaco, with a discussion on the evolution of the lateral epandrial lobe.

A new monotypic genus of Neurigoninae (Diptera: Dolichopodidae), Naglisia gracilis gen. et sp. nov., is described from the Chaco of Mato Grosso do Sul, Brazil. It belongs to the tribe Dactylomyiini and is argued to be closely related to Dactylomyia Aldrich plus Macrodactylomyia Naglis, sharing with them the absence of one claw on the male foreleg, the lateral epandrial lobe fused with ventral surstylus, and the distinct morphology of the postgonites. In addition, an updated identification key to the genera of Dactylomyiini and a short discussion on the homology and evolution of the epandrial lobe and surstylus in the tribe are provided.

New or little-known Neotropical Dolichopodidae (Diptera) (II): genus Hercostomus Loew excluded from the Neotropics.

The Neotropical species of Hercostomus Loew are revised and the following new combinations are proposed: Paraclius panamensis (Van Duzee, 1931) comb. nov. (Panama), P. plumitarsis (Parent, 1931) comb. nov. (Bolivia), P. problematicus (Parent, 1930) comb. nov. (Brazil and Guyana) and Tachytrechus flavimanus (Van Duzee, 1934) comb. nov. (Brazil, Ecuador and Guyana). The type of Hercostomus petulans Parent, 1939 is lost, the species cannot be confidently identified and is here treated as a nomen dubium. As a result, the genus Hercostomus is formally excluded from the Neotropical Region. Paraclius problematicus comb. nov., P. latipes (Aldrich) and Tachytrechus flavimanus comb. nov. are redescribed based on additional material and photographs of type specimens. In addition, Paraclius maculipennis (Van Duzee, 1934) is regarded as a junior synonym of P. problematicus comb. nov. A new species of Paraclius from Costa Rica, P. norrbomi sp. nov. is described in the newly proposed latipes-group, along with P. aberrans Robinson, P. latipes and P. panamensis comb. nov.

Species of Paraclius Loew (Diptera: Dolichopodidae) with bi-lamellate antennal stylus: new combination, new synonym, and two new species.

The species of Paraclius Loew with bi-lamellate arista-like stylus are revised and P. americanus (Schiner, 1868) comb. nov. is transferred from Tachytrechus Haliday and regarded as the senior synonym of P. diplacocerus Capellari, 2013 syn. nov. In addition, two new species with similar antennal morphology are described and illustrated from Brazil: P. bilamellatus sp. nov. (States of Espírito Santo and Goiás) and P. vulcanoae sp. nov. (State of São Paulo). A distribution map and a key to the males of known species of Paraclius with bi-lamellate arista-stylus are provided.

Review of Paraclius arcuatus species-group (Diptera, Dolichopodidae) with description of two new species.

The Paraclius arcuatus species-group is reviewed and includes the following seven species: P. angusticauda Van Duzee, 1933, P. angustipennis Van Duzee, 1929, P. arcuatus (Loew, 1861), P. brooksi sp. nov., P. elongatus Van Duzee, 1930, P. pumilio Loew, 1872, and P. xibun sp. nov. Paraclius angustipennis, P. arcuatus and P. pumilio are redescribed based on photographs of types and additional specimens. Paraclius femoratus Aldrich, 1901 is synonymized with P. arcuatus, syn. nov. and Paraclius magnicornis Van Duzee, 1927 is regarded as a junior synonym of P. pumilio, syn. nov. An identification key, distribution maps and high-resolution photographs of species are provided. In addition, the systematic position of Paraclius is discussed.

Rafaelomyia, a remarkable new genus of South American long-legged flies (Diptera, Dolichopodidae).

A new dolichopodid genus (Diptera, Dolichopodidae), Rafaelomyia Soares, Capellari & Ramos-Pastrana gen. nov., is described and comprises the following five new species from Northern South America: Rafaelomyia exu Soares & Capellari sp. nov. (Cusco, Peru), R. inpa Soares, Capellari & Ramos-Pastrana sp. nov. (Cusco, Peru), R. singularis Soares & Capellari sp. nov. (Cusco, Peru), R. uniamazonia Ramos-Pastrana & Soares sp. nov. (Huila, Colombia), and R. xavieri Soares & Capellari sp. nov. (Cusco, Peru). The new genus is tentatively placed in the subfamily Sympycninae based on a suite of characters traditionally associated with the subfamily: head ovate on anterior view (antenna on top of head), wing with bosse alaire, vein M unbranched into M1 and M2, tibia I with anterodorsal row of setae, male abdomen not pedunculated, with setose tergite 6 and male hypopygium relatively small, despite the lack of anterior preapical setae on femur II and/or III and the presence of a conspicuous flattened posterior slope of mesonotum. The systematic position of the new genus is discussed and an identification key to males is provided.

Three new species of the Neurigona orbicularis species group from Brazil (Diptera: Dolichopodidae).

The Neurigona orbicularis species group (Diptera: Dolichopodidae) is recorded from Brazil for the first time, and three new species are described and illustrated, including figures of the male genitalia: N. lopesi sp. nov. (Tocantins and Gois, Cerrado biome), N. papaveroi sp. nov. (Mato Grosso, Cerrado biome) and N. tingua sp. nov. (Rio de Janeiro, Atlantic Forest biome). Additionally, N. orbicularis Becker, previously known only from the type-locality in Paraguay, is newly recorded from the Brazilian States of Mato Grosso do Sul (Pantanal biome) and So Paulo (Atlantic Forest biome) and its hypopygium is also illustrated. An updated identification key to males of the orbicularis-group is provided.

Review of the Neotropical genus Pseudosympycnus (Diptera: Dolichopodidae), with description of six new species from Brazil and Peru.

The Neotropical stolidosomatine genus Pseudosympycnus Robinson (Diptera: Dolichopodidae) is reviewed and contains 12 species, including six new species that herein are described and illustrated: P. araza sp. nov. (Peru, department of Cusco), P. bickeli sp. nov. (Brazilian States of Pará and Roraima), P. latitibia sp. nov. (Brazilian States of Minas Gerais, Rio de Janeiro and São Paulo), P. maroaga sp. nov (Brazilian State of Amazonas), P. robinsoni sp. nov. (Brazilian State of Acre), and P. sehnali sp. nov. (Brazilian State of Amazonas). All species are diagnosed, male and female terminalia of the genus are illustrated for the first time, high-resolution images of relevant characters are presented and an identification key to males is provided.

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.

Palpi aplenty: new species in the Chrysotus longipalpus species group (Diptera: Dolichopodidae).

Four new Nearctic species belonging to the Chrysotus longipalpus species group are described: Chrysotus keyensis sp. nov. (Florida), Chrysotus mccreadiei sp. nov. (Alabama), Chrysotus mystax sp. nov. (Alabama), and Chrysotus plumarista sp. nov. (Alabama). This brings the number of known species in this group to twelve. A key to species of males of the C. longipalpus species group and new distribution records are provided.

Timeless standards for species delimitation.

Recently a new species of bombyliid fly, Marleyimyia xylocopae, was described by Marshall & Evenhuis (2015) based on two photographs taken during fieldwork in the Republic of South Africa. This species has no preserved holotype. The paper generated some buzz, especially among dipterists, because in most cases photographs taken in the field provide insufficient information for properly diagnosing and documenting species of Diptera.

Realism in systematics through biogeographical consilience.

There is an overlooked gap between any phylogenetic hypothesis and the natural world shaped by historical evolutionary processes, since the main concern during phylogenetic analyses is solely the search for congruence among characters under a defined criterion. Given a scientific realistic view, however, phylogenetic hypotheses are scientific theories that try to depict the historical series of cladogenetic events among biological entities. In this sense, the challenge is to establish a form of measuring the degree of truthfulness of our phylogenetic hypotheses. Here, we advocate the use of consilient biogeographical hypotheses to recognize the biological meaning of a phylogenetic inference apart from its instrumentalist value. Our proposal is based on the assumption that robust biogeographical hypotheses allows us to be close to the real evolutionary history of taxa. © The Willi Hennig Society 2011.