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Long-distance migration of insects impacts food security, public health, and conservation–issues that are especially significant in Africa. Windborne migration is a key strategy enabling exploitation of ephemeral havens such as the Sahel, however, its knowledge remains sparse. In this first cross-season investigation (3 years) of the aerial fauna over Africa, we sampled insects flying 40–290 m above ground in Mali, using nets mounted on tethered helium-filled balloons. Nearly half a million insects were caught, representing at least 100 families from thirteen orders. Control nets confirmed that the insects were captured at altitude. Thirteen ecologically and phylogenetically diverse species were studied in detail. Migration of all species peaked during the wet season every year across localities, suggesting regular migrations. Species differed in flight altitude, seasonality, and associated weather conditions. All taxa exhibited frequent flights on southerly winds, accounting for the recolonization of the Sahel from southern source populations. “Return” southward movement occurred in most taxa. Estimates of the seasonal number of migrants per species crossing Mali at latitude 14°N were in the trillions, and the nightly distances traversed reached hundreds of kilometers. The magnitude and diversity of windborne insect migration highlight its importance and impacts on Sahelian and neighboring ecosystems.

The planthopper family Delphacidae is a speciose lineage of phloem‐feeding insects, with many species considered as pests of economic significance on essential world food commodities (including rice, maize, wheat, barley and sugar cane). Despite their economic importance, evolutionary relationships among delphacids, particularly those within the speciose tribe Delphacini, are largely unknown. Presented here are the results of a phylogenetic investigation of Delphacidae based on DNA nucleotide sequence data from four genetic loci (18S rDNA, 28S rDNA, wingless and cytochrome oxidase I) and 132 coded morphological characters. The resulting topologies are used to test the higher classification of Delphacidae and to examine evolutionary patterns in host–plant associations. Our results generally support the higher classifications of Delphacidae proposed by Asche, Emeljanov and Hamilton, and suggest that the rapid diversification of the Delphacini was associated with host shifts to, and within, Poaceae, and specifically from C3 to C4 grasses.

Six new species from Mesoamerica are described and illustrated into the formerly monotypic genus Parkana. These species are segregated into 3 subgenera, Parkana s.s. (bearing a large dorsal process on the aedeagus) consisting of 5 species, and a single species each in Furcoparca new subgenus (with the median processes of the pygofer formed into a large forked process), and Litoparca new subgenus (lacking both features, genitalia relatively simple, aedeagus bearing lateral teeth). The new species are P. (P.) mirasol, P. (P.) nigra, P. (P.) pallida, P. (P.) tres, P. (F.) chico (all from Mexico, except P. nigra also from Guatemala), and P. (L.) costa (Costa Rica). Keys are provided to subgenus and species. Parkana was previously known only from the type species (P. alata) from western United States. The diversity of Mesoamerican delphacid species is briefly discussed.

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