Paederinae, a diverse subfamily of rove beetles (Staphylinidae), is poorly explored with an outdated subtribal and generic classification lacking proper phylogenetic perspective. Therefore, the discovery of two Baltic amber fossil specimens resembling the genera Micrillus and Scymbalium, which are particularly challenging in terms of systematics, called for a thorough analysis to infer their phylogenetic position and their ecological requirements. The fossils were examined with light microscopy supplemented by X-ray micro-computed tomography, and then scored into a Paederinae-specific matrix of 99 morphological characters, along with a broad sample of recent Paederinae and non-paederine outgroups. Morphological phylogenetic analyses were conducted, using Bayesian Inference and Maximum Parsimony. The obtained phylogeny confirmed that the genera Scymbalium and Micrillus form a lineage outside Lathrobiina; therefore, both genera are now classified as Lathrobiini incertae sedis pending a more inclusive phylogenetic work on Paederinae. The analysis firmly placed both fossils in that recent lineage, albeit rendering Micrillus paraphyletic with respect to Scymbalium. Without a more extensive analysis based on the revised world fauna, any systematic changes would be premature. Thus, the fossils are described as Micrillus electrus, sp. nov. and Scymbalium phaethoni, sp. nov. in accordance with the current diagnoses of both genera. Given that the recent species of Micrillus and Scymbalium are predominantly thermophilic and mainly confined to dry open landscapes in Africa, southern Eurasia and Australia, the finding of Baltic amber representatives implies the very diverse landscape and the equable (sub)tropical palaeoclimatic conditions of the Eocene amberiferous ‘forest’, the latter being the subject of continued debates.

Baltic amber is a rich source of fossilized organisms and a valuable tool for evolutionary, biogeographical and palaeoenvironmental research. Because it is found in several deposits around the Baltic Sea, the exact area of origin, age in the Eocene and palaeoenvironment of the amber forest form a subject for ongoing discussion. Furthermore, there is a puzzling connection between Eocene climate change and the co‐occurrence of thermophilic and temperate insect taxa in Baltic amber, sometimes even in the same inclusions. We revisit these issues through a new piece of evidence: the rare South‐East Asian rove beetle genus Dysanabatium (11 extant species) found to be abundant in Baltic amber. We describe four new extinct species of Dysanabatium based on 13 specimens from 8 amber pieces collected in Denmark, Poland, Ukraine and Russia. These species are Dysanabatium kechrimparense sp. nov., D. aenaum sp. nov., D. damgaardi sp. nov. and D. johannesi sp. nov. The occurrence of one species, D. kechrimparense sp. nov., in the amber from all countries, as well as its co‐occurrence with D. damgaardi sp. nov. in one amber piece from Russia, suggest a possible common origin of Baltic amber from all these deposits. Dysanabatium adds to a plethora of fossil species congeneric with extant species restricted to South‐East Asia, which points to the warm and equable climate of the north European Eocene amber forest.

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