The origin of taxa presenting a disjunct distribution between Africa and Asia has puzzled biogeographers for more than a century. This biogeographic pattern has been hypothesized to be the result of transoceanic long‐distance dispersal, Oligocene dispersal through forested corridors, Miocene dispersal through the Arabian Peninsula or passive dispersal on the rifting Indian plate. However, it has often been difficult to pinpoint the mechanisms at play. We investigate biotic exchange between the Afrotropics and the Oriental region during the Cenozoic, a period in which geological changes altered landmass connectivity. We use Baorini skippers (Lepidoptera, Hesperiidae) as a model, a widespread clade of butterflies in the Old World tropics with a disjunct distribution between the Afrotropics and the Oriental region. We use anchored phylogenomics to infer a robust evolutionary tree for Baorini skippers and estimate divergence times and ancestral ranges to test biogeographic hypotheses. Our phylogenomic tree recovers strongly supported relationships for Baorini skippers and clarifies the systematics of the tribe. Dating analyses suggest that these butterflies originated in the Oriental region, Greater Sunda Islands, and the Philippines in the early Miocene c. 23 Ma. Baorini skippers dispersed from the Oriental region towards Africa at least five times in the past 20 Ma. These butterflies colonized the Afrotropics primarily through trans‐Arabian geodispersal after the closure of the Tethyan seaway in the mid‐Miocene. Range expansion from the Oriental region towards the African continent probably occurred via the Gomphotherium land bridge through the Arabian Peninsula. Alternative scenarios invoking long‐distance dispersal and vicariance are not supported. The Miocene climate change and biome shift from forested areas to grasslands possibly facilitated geodispersal in this clade of butterflies.

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Members of the skipper tribe Baorini generally resemble each other and are characterized by dark brown wings with hyaline white spots. These shared characteristics have caused difficulties with revealing the relationships among genera and species in the group, and some conflicting taxonomic views remain unresolved. The present study aims to infer a more comprehensive phylogeny of the tribe using molecular data, to test the monophyly of the tribe as well as the genera it includes in order to clarify their taxonomic status, and finally to revise the current classification of the group. In order to reconstruct a phylogenetic tree, the mitochondrial COI-COII and 16S genes as well as the nuclear EF-1α and 28S genes were analyzed using parsimony, maximum likelihood, and Bayesian inference. The analysis included 67 specimens of 41 species, and we confirmed the monophyly of Baorini, and revealed that 14 genera are well supported. The genus Borbo is separated into three clades: Borbo, Pseudoborbo, and Larsenia gen. nov. We confirmed that Polytremis is polyphyletic and separated into three genera: Polytremis, Zinaida, and Zenonoida gen. nov., and also confirmed that the genus Prusiana is a member of the tribe. Relationships among some genera were strongly supported. For example, Zenonia and Zenonoida were found to be sister taxa, closely related to Zinaida and Iton, while Pelopidas and Baoris were also found to cluster together.

The systematic positions of two hesperiid genera, Apostictopterus and Barca (Lepidoptera: Hesperiidae), remain ambiguous. We sequenced and annotated the two mitogenomes of Apostictopterus fuliginosus and Barca bicolor and inferred the phylogenetic positions of the two genera within the Hesperiidae based on the available mitogenomes. The lengths of the two circular mitogenomes of A. fuliginosus and B. bicolor are 15,417 and 15,574 base pairs (bp), respectively. These two mitogenomes show similar AT skew, GC skew, codon usage and nucleotide bias of AT: the GC skew of the two species is negative, and the AT skew of A. fuliginosus is negative, while the AT skew of B. bicolor is slightly positive. The largest intergenic spacer is located at the same position between trnQ and ND2 in A. fuliginosus (73 bp) and B. bicolor (72 bp). Thirteen protein-coding genes (PCGs) start with ATN codons except for COI, which starts with CGA. The control regions of both mitogenomes possess a long tandem repeat, which is 30 bp long in A. fuliginosus, and 18 bp in B. bicolor. Bayesian inference and maximum likelihood methods were employed to infer the phylogenetic relationships, which suggested that A. fuliginosus and B. bicolor belong in the subfamily Hesperiinae.

The Oriental tribe Aeromachini (Lepidoptera: Hesperiidae: Hesperiinae) is diverse and widespread, but its monophyly and circumscription remain unresolved. In this study, we inferred phylogenetic relationships within the tribe using two mitochondrial (16S and COI-COII) and two nuclear genes (EF-1 and Wingless) from 71 samples representing all of the known genera of Aeromachini (s.l.). Phylogenetic topologies obtained from two model-based methods (maximum-likelihood and Bayesian inference) were largely congruent, showing that Aeromachini was monophyletic. Many genera within Aeromachini were polyphyletic, especially Arnetta, Thoressa, Ampittia and Sovia. Based on these results, we propose a new classification consisting of 14 genera, of which two are newly described: Halpemorpha gen.n. and Praethoressa gen.n. Ampittia and Ochus are restructured, with: (i) Ampittia nana and Ampittia dalailama moved to Aeromachus, (ii) new combinations proposed for the remaining Ampittia species, and (iii) a new combination, Ampittia subvittatus comb.n., proposed. The Oriental members of the genus Arnetta belong to this tribe, but the African Arnetta hyposticta was found to be embedded into the outgroup and closely related to Isoteinon. We propose that hyposticta be reinstated in the genus Galerga Mabille, along with two other African species (fito and ellipsis). Thoressa is polyphyletic, with three distinct lineages. The type species Thoressa masoni forms a clade closely related to the sister genera Sebastonyma and Parasovia. We thus describe Praethoressa gen.n. to include the species varia (formerly of Thoressa), and transfer the remaining Thoressa to Pedesta, which is confirmed as a valid genus. Although the relationships of some genera remained unsolved in our work, the present phylogenetic hypothesis will serve as a reference for further studies. A secondary calibration was used to estimate the divergence time, which indicated that the diversification of Aeromachini started in the late Eocene and early Oligocene (c. 34.22 Ma). Further, ancestral range estimates indicated that the common ancestor of Aeromachini originated in Southeast Asia. Diversification in situ and range expansion to adjacent areas have played essential roles in the evolution of Aeromachini, but founder-event speciation and vicariance also have likely been important factors in shaping the biogeographical history of this tribe.This published work has been registered on ZooBank, http://zoobank.org/urn:lsid: zoobank.