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This paper explores the distributional data of 4,224 Tipulidae (Insecta: Diptera) species to search for endemism patterns in a worldwide scale and to test the extent to which the global patterns of endemism of the group fit into previously proposed regionalization schemes, particularly Wallace's system and recent revisions of it. Large scale areas of endemism are assessed using the grid-based method implemented in VNDM. VNDM depends on the prior definition of the grid size for analysis, but a criterion for choosing beforehand a particular grid size is not clear. The same holds for the choice of the level of similarity in species composition selected for the calculation of consensus areas. In our study, we developed a methodological approach that helped defining objective criteria for choosing suitable values for these critical variables. Large-scale areas of endemism around the globe are identified and ranked according to endemicity levels: 1--West Palaearctic, 2--Nearctic, 3--East Palaearctic-Oriental, 4--West North America, 5--Australia, 6--Neotropical, 7--Sub-Saharan Africa, 8--Palaearctic, and 9--Middle East. Our main conclusion is that there are still some limitations in applying biogeographical classifications proposed mostly on the basis of vertebrate distribution to other taxonomic groups, such as the Tipulidae. While there is a general congruence of the broad-scale areas of endemism of tipulids with previously proposed regionalization schemes, for some areas, the sharpness of boundaries between traditional regions is not so acute, due to a great level of overlap of part of its biotic elements.

A growing number of biogeographical methods have attempted to describe formal means of reconstructing

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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.

We present a study of the endemicity patterns in the Brazilian Atlantic Forest on the basis of the distribution of 107 fly species belonging to 24 genera of 15 families. This is the first picture of endemism for Diptera in the Atlantic Forest. Instead of the traditional grid of geographical coordinates, we used a system of topographic units (TUs) for the analysis, delimited after gathering information on rivers and altitude for each state and country. A parsimony analysis of the data matrix with the species records for the TUs was performed, named topographic-unit parsimony analysis (TUPA). The same distributional data was used in a NDM/VNDM analysis. The combination of the resulting patterns from both analyses indicated the existence of the following three major areas of endemism for flies in the Atlantic Forest: a Northern Atlantic Forest, north of Rio Doce; a Southern Atlantic Forest, south of Rio Doce along the coast, extending to the west and to the south at the level of the state of Paraná; and a Semideciduous Seasonal Forest, west to the ombrophilous forest along the coast. None of these areas seems to be shaped solely by vicariance events. They can possibly be the result of biotic fusion of ancestral areas of endemism as a result of barrier collapse and secondary overlap of sister biotas, a hypothesis yet to be tested. The recognition of a separate area of endemism for flies in the Semideciduous Forest agrees with phytogeographical reconstructions and raises an important alert for the scarcity of biological reserves for this vegetation.

Biogeography deals with the combined analysis of the spatial and temporal components of the evolutionary process. To this purpose, biogeographical analysis should consider two extra steps: a reciprocal illumination step, and a consilience step. Even if the traditional challenges of biogeography were successfully handled, the obtained hypothesis is not necessarily meaningful in biogeographical terms--it needs continuous test in the light of external hypotheses. For this reason, a concept analogous to Hennig's reciprocal illumination is valuable, as well as a sort of biogeographical consilience in Whewell's sense. Firstly, through the search for different classes of evidence, information useful to improve the hypothesis can be accessed via reciprocal illumination. Following, a more general hypothesis would arise through a consilience process, when the hypothesis explains phenomena not contemplated during its construction, as the distribution of other taxa or the existence (or absence) of fossils. This procedure aims to evaluate the robustness of biogeographical hypotheses as scientific theories. Such theories are reliable descriptions of how life changes its form both in space and time, putting historical biogeography close to Croizat's statement of evolution as a three dimensional phenomenon.

Most biogeographical studies propose that southern temperate faunal disjunctions are either the result of vicariance of taxa originated in Gondwana or the result of transoceanic dispersal of taxa originated after the breakup of Gondwana. The aim of this paper is to show that this is a false dichotomy. Antarctica retained a mild climate until mid-Cenozoic and had lasting connections, notably with southern South America and Australia. Both taxa originally Gondwanan and taxa secondarily on Gondwanan areas were subjected to tectonicinduced vicariance, and there is no need to invoke ad hoc transoceanic dispersal, even for post-Gondwanan taxa. These different elements with circumantarctic distributions are here called 'allochronic taxa' -taxa presently occupying the same area, but whose presence in that area does not belong to the same time period. This model allows accommodation of conflicting sources of evidence now available for many groups with circumantarctic distributions. The fact that the species from both layers are mixed up in the current biodiversity implies the need to use additional sources of evidence -such as biogeographical, palaeontological, geological and molecular -to discriminate which are the original Gondwanan and which are post-Gondwanan elements in austral landmasses.