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.

There is a growing necessity to integrate morphological and genetic studies. This paper proposes a new technique that allows DNA extraction of arthropods while still keeping intact the entire morphology of the specimens. The technique uses Proteinase K to dissolve protein tissues and preserve the chitinous exoskeleton of specimens. The method is fast, cheap, non-toxic, and allows for good morphological preparations of specimens retaining much of their tridimensional structure. The methodology works fine with specimens preserved in different kinds of media, such as for dry (pinned) specimens, and specimens preserved in Ethanol. In addition, it allows the extraction of DNA from fresh specimens, as well as from specimens preserved for a long time. The technique works well for morphological studies alone, but allows the generation of an associated genomic library at an individual-scale. Among the advantages of the new technique is the possibility of extracting DNA from the entire specimen (necessary for the study of diseases transmitted by arthropod vectors), while still keeping the morphology intact for correct taxonomic identification. In addition, in comparison with methods that extract DNA from small tissue samples (e.g., from legs or wings), the method allows for the extraction of a larger amount of DNA and is better suited for small specimens.

Tropical forests are among the most biodiverse biomes on the planet. Nevertheless, quantifying the abundance and species richness within megadiverse groups is a significant challenge. We designed a study to address this challenge by documenting the variability of the insect fauna across a vertical canopy gradient in a Central Amazonian tropical forest. Insects were sampled over two weeks using 6-m Gressitt-style Malaise traps set at five heights (0 m–32 m–8 m intervals) on a metal tower in a tropical forest north of Manaus, Brazil. The traps contained 37,778 specimens of 18 orders of insects. Using simulation approaches and nonparametric analyses, we interpreted the abundance and richness of insects along this gradient. Diptera, Hymenoptera, and Coleoptera had their greatest abundance at the ground level, whereas Lepidoptera and Hemiptera were more abundant in the upper levels of the canopy. We identified species of 38 of the 56 families of Diptera, finding that 527 out of 856 species (61.6%) were not sampled at the ground level. Mycetophilidae, Tipulidae, and Phoridae were significantly more diverse and/or abundant at the ground level, while Tachinidae, Dolichopodidae, and Lauxaniidae were more diverse or abundant at upper levels. Our study suggests the need for a careful discussion of strategies of tropical forest conservation based on a much more complete understanding of the three-dimensional distribution of its insect diversity.

At least one million extant insect species have been described on Earth