Insect mitochondrial genomes (mtDNA) are usually double helical and circular molecules containing 37 genes that are encoded on both strands. The arrangement of the genes is not constant for all species, and produces distinct gene orders (GOs) that have proven to be diagnostic in defining clades at different taxonomic levels. In general, it is believed that distinct taxa have a very low chance of sharing identically arranged GOs. However, examples of identical, homoplastic local rearrangements occurring in distinct taxa do exist. In this study, we sequenced the complete mtDNAs of the ants Formica fusca and Myrmica scabrinodis (Formicidae, Hymenoptera) and compared their GOs with those of other Insecta. The GO of F. fusca was found to be identical to the GO of Dytrisia (the largest clade of Lepidoptera). This finding is the first documented case of an identical GO shared by distinct groups of Insecta, and it is the oldest known event of GO convergent evolution in animals. Both Hymenoptera and Lepidoptera acquired this GO early in their evolution. Using a phylogenetic approach combined with new bioinformatic tools, the chronological order of the evolutionary events that produced the diversity of the hymenopteran GOs was determined. Additionally, new local homoplastic rearrangements shared by distinct groups of insects were identified. Our study showed that local and global homoplasies affecting the insect GOs are more widespread than previously thought. Homoplastic GOs can still be useful for characterizing the various clades, provided that they are appropriately considered in a phylogenetic and taxonomic context.

The Tetramorium striativentre species group is revised. Workers and queens of the species of this group are characterized by the unique for all other Palaearctic Tetramorium species feature: the first gastral tergite, or at least its anterior half, is very densely and distinctly longitudinally striato-punctated. We place six species to this group, including two new ones: T. striativentre Mayr, T. schneideri Emery, T. kabulistanicum Pisarski, T. saudicum Sharaf, T. sabatinellii sp. n. from Jordan, and T. pisarskii sp. n. from Afghanistan. Additions to the diagnosis of T. striativentre and T. schneideri and the first descriptions of males of these two species are provided, and a key to species of this group is compiled.

The Canary Islands are a biologically important archipelago hosting many unique species, whose myrmecofauna is peculiarly rich in both endemic and introduced species. Lepisiota frauenfeldi cfr. kantarensis Forel, 1911 is reported for the first time from Fuerteventura and Tenerife. It is the second species of Lepisiota introduced in the archipelago in the last few years, and one of the few documented cases in which Lepisiota frauenfeldi (Mayr, 1855) s.l. acts as a successful tramp species. Comments are also given on taxonomic problems involving the L. frauenfeldi-group and related taxa. Finally, new additional information and comments are presented on the distribution of other alien ants species from the Canary Islands [Lasius neglectus Van Loon, Boomsma & Andrásfalvy, 1990, Lepisiota capensis (Mayr, 1862 and Paratrechina longicornis (Latreille, 1802)].

The ant genus Myrmecina, whose diversity is mostly concentrated in SE-Asia and Oceania, counts four W-Palearctic species. The extremely euryecious and well-studied Myrmecina graminicola occurs from Iberia to the Caucasus and from the Maghreb to Scandinavia, while three little-known species (M. atlantis, M. melonii and M. sicula) coexist with M. graminicola in their narrow Maghrebian, Sardinian and Sicilian ranges, respectively. Myrmecina sicula has been described about 140 years ago from a single site and two specimens only. Their unique morphology suggested the validity of this taxon ever since, but no additional specimens were found in the following century. We present the results of decades of sampling efforts across Sicily, resulting in the collection of M. graminicola from 70 sites and M. sicula from 13 sites. We confirm M. sicula unique morphological identity and report on the marked distributional and ecological differences between the two species. Myrmecina graminicola is widespread and inhabits diverse, mainly forested habitats from lowland to high mountain sites, while M. sicula was found in a very narrow region of old carbonate platform between NW-Sicily and the Egadi Islands, mostly in sparsely vegetated sites at mid to low-altitude. Reviewing their common morphological and biogeographic traits, we propose to consider M. atlantis, M. melonii and M. sicula as a distinct M. sicula complex, whose identity and history deserves further investigation through molecular analyses.

Hypoponera abeillei is the sole member of the otherwise exclusively Afrotropical abeillei group to occur in the West-Palearctic and since its first description on the basis of two Corsican workers in 1881, it remained little-known. Workers of this species are thought to entirely lack eyes, a rare trait among ants of the region, yet their lifestyle remains undocumented. On the other hand, the male caste has been described from 4 Tunisian specimens in 1921, and queens remained so far undescribed. We present an updated description of the male caste based on 45 specimens and a first description of the queen caste based on 14 specimens. The H. abeillei material we examined comes from Italy, Spain and Malta (mostly originating from coastal localities), and comprises 11 inedit distribution records, including the first findings in the islands of Mallorca, Malta and Sardinia. Moreover, we provide a first phenological overview of the species’ nuptial flights. Our data show that H. abeillei sexuals flight during the summer, mostly in August, and demonstrate that they can easily be distinguished from all the other Hypoponera species inhabiting the Mediterranean region based on their morphology. The remarkable diversity of Mediterranean Hypoponera males and queens suggest that sexuals may have a role in future attempts to understand relationships within this genus, yet the number of species in which sexual castes are documented is still extremely reduced.