Fossils are critical for understanding the evolutionary diversification, turnover, and morphological disparification of extant lineages. While fossils cannot be sequenced, phenome-scale data may be generated using micro-computed tomography (µ-CT), thus revealing hidden structures and internal anatomy, when preserved. Here, we adduce the male caste of a new fossil ant species from Miocene Ethiopian amber that resembles members of the Aneuretinae, matching the operational definition of the subfamily. Through the use of synchrotron radiation for µ-CT, we critically test the aneuretine-identity hypothesis. Our results indicate that the new fossils do not belong to the Aneuretinae, but rather the Ponerini (Ponerinae). Informed by recent phylogenomic studies, we were able to place the fossils close to the extant genus Cryptopone based on logical character analysis, with the two uniquely sharing absence of the subpetiolar process among all ponerine genera. Consequently, we: (1) revise the male-based key to the global ant subfamilies; (2) revise the definitions of Aneuretinae, Ponerinae, Platythyreini, and Ponerini; (3) discuss the evolution of ant mandibles; and (4) describe the fossils as †Desyopone hereon gen. et sp. nov. Our study highlights the value of males for ant systematics and the tremendous potential of phenomic imaging technologies for the study of ant evolution.

The Early Miocene (16–23 Mya) amber of Ethiopia constitutes a new source of fossil ants for Africa, where they are otherwise poorly documented. Here we report a diversified assemblage of six subfamilies and at least 19 genera that are still predominantly alive in the Afrotropics today. In this first account, a particular reference is made to the subfamily Dolichoderinae, with the description of two new species: Technomyrmex svojtkai Perrichot & Engel sp. nov. and Ravavy goldmani Boudinot & Perrichot sp. nov. The first is illustrated and described based on synchrotron-radiation microcomputed tomography, and the second represents the first fossil record for the tribe Bothriomyrmecini and Ravavy, a Malagasy and Afrotropical genus that was hitherto monotypic. The ant composition in Ethiopian amber is congruent with the global pattern emerging across ants and showing a Neogene diversification almost exclusively within extant genera.

A new, extinct species of Allodia Winnertz is described from early Miocene amber of Ethiopia. Allodia paleoafricana sp. nov. is mostly characterized by the scutum with strong anteromarginal, dorsocentral, and lateral setae and the wing with the stem of the M-fork slightly shorter than the vein r–m and the base of the M4–CuA fork aligned with the base of r–m. The assignment to any of the two subgenera Allodia stricto sensu or Brachycampta Winnertz remains equivocal as the fossil intermingles traits found in both taxa. Allodia is known mostly from the Palearctic region, while only a few species have been described from Africa. In this regard, the new fossil species from Ethiopia brings significant new information regarding the Afrotropical distribution and natural history of the genus.

The fossil record reveals palaeoecological interactions between plants and insects. This study describes a singular conifer xylite specimen from the Baltic amber-bearing deposits, with preserved resin ducts and cylindrical insect borings designated as Bivium ichnogen. nov. with Bivium diluviandi ichnosp. nov. The borings, characterized by longitudinal tunnels connected by cross tunnels and chambers, were likely created by xylophagous beetles belonging to the family Curculionidae (subfamily Scolytinae). The associated resin production reflects an adaptive plant response to insect and fungal activity, evidenced by fungal hyphae preserved within the specimen. This work contributes to the knowledge of Baltic amber stratigraphy, and the formation of resin-bearing deposits, and shows, that the wood-boring insects may have been a cause, among others, of resin exudation.