Archaeocercoides puchkovi Simutnik, gen. et sp.nov., and Rovnopositor voblenkoi Simutnik, gen. et sp.nov., are described and illustrated based on female specimens from late Eocene Rovno amber. Like most previously described Eocene Encyrtidae, the new taxa differ from the majority of extant encyrtids by the apical or nearly apical position of the cerci, the short radicle, and the long marginal vein of the forewing. Both new genera are characterized by a strongly reduced ovipositor sheaths but long and upwardly bent ovipositor stylets (in the “ovipositing position”), a stigmal vein with a long uncus, and the absence of a filum spinosum. The new genera differ from each other in the width of frontovertex, the location of the cerci, and the lengths of funicular segments and marginal vein. A. puchkovi was fossilized near a Coccoidea crawler.

Sulia glaesaria Simutnik, 2015 (Chalcidoidea, Encyrtidae), originally described from late Eocene Danish amber, is reported in coeval Rovno amber. A revised diagnosis of this genus is provided based on the new specimen and high-resolution photomicrographs of the holotype. Some character states, such as a short radicle, clypeus with long lateral margins, the presence of a strigil and basitarsal comb, spur vein of the hind wing, costal cell of hind wing along entire marginal vein with single line of long setae, and almost vertical syntergum with abruptly reflexed extension apically are reported in this species for the first time.

A new species from the fossil ant genus Cataglyphoides Dlussky, 2008, C. dlusskyi sp.n., is described from the Rovno amber (Ukraine). A new record of C. constrictus (Mayr, 1868) from the Baltic amber (age of both ambers is late Eocene, Priabonian, 33.9-37.2 Ma) and additional diagnostic features of this species are provided. C. dlusskyi resembles C. constrictus but well differs from the latter mainly by the absence of standing hairs on the body, absence of the longitudinal carina on the clypeus, by position of the eyes and the much shorter genae and by character of the standing pilosity on the appendages (C. dlusskyi has very fine and short whitish subdecumbent to suberect hairs, but C. constrictus has coarse brownish bristles). C. dlusskyi differs from C.

Aneuretinae is an enigmatic ant subfamily with poorly defined morphological boundaries. Aneuretus simoni Emery, 1893, found only in Sri Lanka, is a “living fossil”, the only known extant species of Aneuretinae. In the distant past, however, Aneuretinae was more diverse and widespread, including eight extinct genera spread across North America, Europe, and the Russian Far East. Here, we report two fossil Aneuretinae species, Protaneuretus succineus Wheeler, 1915 and Paraneuretus tornquisti Wheeler, 1915, found in late Eocene (Priabonian, 37.8–33.9 Ma) Rovno amber (Ukraine), providing distinguishing morphological features and measurements. These species, the first recorded Aneuretinae in Rovno amber, were originally described from Baltic amber of similar Priabonian age. These new records raise the number of reported ants in Rovno amber to 77 species from 39 genera and 9 subfamilies, and indicate that in the late Eocene Aneuretinae were distributed both on the northern and southern coasts of the Paratethys. Fossil evidence suggests that Aneuretinae originated in the Northern Hemisphere and only entered India and Sri Lanka after the Indian subcontinent collided with Asia ~59 Ma. Why Aneuretinae survived to the present only in Sri Lanka remains a mystery.

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