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Xenophagus simutniki sp. n. is described from a late Eocene Rovno amber specimen. The new species is similar to the fossil Xenophagus popovi Lyubarsky et Perkovsky, 2017 from the late Eocene Baltic amber (W Russia), differing in the medially notched anterior margin of the pronotum. The Rovno xenosceline fauna is the richest among both extant and extinct faunas. This fauna includes the extinct genera Xenophagus Lyubarsky & Perkovsky, 2017 and Xenohimatium Lyubarsky & Perkovsky, 2012, which are closest to the extant Mediterranean Xenoscelis Wollaston 1864 and the representative of the extant boreal genus Zavaljus Reitter, 1880. A key to extinct species of the subfamily Xenoscelinae is presented. The possible reasons of xenoscelines abundance in European amber forests are discussed.

Fossil weevils of the subfamily Molytinae are currently represented by 103 species in 42 genera from 14 tribes. Fossil records of the tribe Aedemonini are known from the Eocene of Europe. This tribe makes up 22% of the London Clay weevil specimens identified to the genus level and 16% of the Curculionidae genera. At present, the distribution of this tribe is mainly paleotropical, but it was very prominent in the paratropical biota of the London Clay in the early Eocene, and it was still represented in the biota of the amber forests of Europe that retained some tropical elements in the Priabonian. A new species, Electrorhinus vlaskini n. sp., from the tribe Aedemonini of the subfamily Molytinae, is described from Rovno amber. It differs from E. friedhelmi in the smaller body size, finely faceted eyes, a coarser rugose pronotum, and sparser scales on the body. A list of the fossil Molytinae is compiled. This is the first record of a weevil of the subfamily Molytinae in Rovno amber, and the second finding of a representative of the genus Electrorhinus in the late Eocene and the third record of a species of Aedemonini preserved as a fossil. A key to European species of Molytinae with a rostral channel from Europe is given.

From the modern distribution of the tribes Anypotactini and Eudiagogini (Coleoptera, Curculionidae), it can be assumed that the climate of the late Eocene amber forests was similar to that of the Valdivian temperate forests. A new species, Paonaupactus zosimovichi sp. n. from the tribe Anypotactini of the subfamily Entiminae is described from Late Eocene Rovno amber. It differs from Paonaupactus gracilis by its rarer, decumbent scales on the elytral interstriae, elytral interstriae, which are clearly visible between scales, and its smaller body size. This is the third species of the genus Paonaupactus found in Rovno amber.

Protaphycus shuvalikovi Simutnik gen. et sp. nov. , the smallest fossil Encyrtidae, is described and illustrated based on female specimen from late Eocene Rovno amber. Like most previously described Eocene Encyrtidae, the new taxon differs from the majority of extant encyrtids by the subapical position of the cerci, the relatively long marginal vein of the forewing, a distinctly swollen but not triangular parastigma, and a seta marking the apex of the postmarginal vein is not any longer than others on this vein. The new genus is characterized by the presence of a filum spinosum and the hypopygium reaching way past the apex of syntergum. This combination of the character states is known only in a few representatives of extant Encyrtinae. The new genus, probably, most closely related to the extant genus Aphycus Mayr, 1876.

Glesoconomorphus ekaterinae sp. nov. (Coleoptera, Mycteridae), representing the first ever fossil species of Coleoptera from the Volyn Region of Ukraine and the first mycterid from late Eocene Rovno amber, is described and illustrated. A key to species of the fossil mycterid genus Glesoconomorphus Alekseev, Pollock & Bukejs, 2019 is presented. The systematic position of Glesoconomorphus within Eurypinae J. Thomson, 1860 is briefly discussed. The oldest finding of phoretic Winterschmidtiidae Oudemans, 1923 mites, found on the type specimen of the new beetle species, is reported.

The first fossil Typhlocybinae inclusions from Eocene Rovno amber are described and illustrated. They include two new monotypic genera of the extinct tribe Protodikraneurini, Retrorsotettix n. gen. with type species R. vlaskini n. sp. and Protoparallaxis n. gen. with type species P. clavatus n. sp. Also described and illustrated are two new monotypic genera of the extant tribe Dikraneurini, Eodikraneura n. gen. with type species E. obscura n. sp. and Rovnodikra n. gen. with type species Rovnodikra longipes n. sp. Retrorsotettix is the oldest leafhopper known to exhibit a false eyespot and false leg markings on the forewing, representing an early acquisition of a defensive strategy against visual predators. Appearance of a small insect with false eyespots in the Eocene fossil record may reflect increased pressure by visual predators, especially crown ornithuromorph insectivorous birds. Such birds and small insect prey with false eyespots remain unknown in the Cretaceous. Eodikraneura exhibits a unique condition of the hind wing venation in which radius posterior and media anterior veins are confluent for a short distance but then diverge before separately reaching the submarginal vein. This presumably represents a morphological transition between the Protodikraneurini, in which hind-wing radius posterior and media anterior veins are completely separate and connected by a radial-medial crossvein, and Dikraneurini, in which radius posterior and media anterior veins are completely confluent distally. A key to genera of Protodikraneurini is provided.

A new species, Formica ribbeckei Radchenko & Perkovsky, sp. nov. , is described based on four workers from late Eocene Rovno amber (Ukraine). It most resembles F. flori Mayr, 1868 but differs from the latter mainly by the 5-segmented maxillary palps with the preapical segment subequal in length to the apical one, and by the shorter first funicular segment. Fossil F. luteola Presl, 1822, F. trigona Presl, 1822, F. macrognatha Presl, 1822 and F. quadrata Holl, 1829 are considered incertae sedis in Formicidae. Thus, ten valid Formica Linnaeus, 1758 species (including F. ribbeckei ) are known now from late Eocene European ambers. The diversity of Formica in the early and middle Eocene deposits of Eurasia and North America is considered. It is assumed that the genus Formica most likely arose in the early Eocene.

A new genus and species of the braconid parasitoid subfamily Doryctinae, Eocenhecabolus kotenkoi gen. et sp. nov. , from the late Eocene Rovno amber are described and illustrated. Eocenhecabolus gen. nov. is the first unambiguously extinct Doryctinae genus. This genus is described from the male and characterised by the followings features: in the fore wing by the postfurcal position of the recurrent vein (m-cu) relatively to the first radiomedial vein (2-SR), and a distally open brachial (second subdiscal) cell; in the hind wing by the presence of the elementary stigma-like enlargement on the distal half of the costal (1-SC+R) vein. The different types of stigma-like enlargements found in the hind wings of males in the subfamily Doryctinae are discussed.

Electronoyesella antiqua Simutnik, gen. et sp. nov. , is described and illustrated based on a female specimen from late Eocene Rovno amber. Like most previously described Eocene Encyrtidae, the new taxon differs from the majority of extant ones in a number of features. Sclerotised metasomal structures, similar to the paratergites of extant Tetracneminae, are seen here for the first time in fossils. The new genus is characterized also by the frontovertex with four vertical rows of piliferous punctures and the face also with intricate sculpture; notauli are present as small but distinct depressions, only anteriorly; the apex of metatibia with a peg originating from a round, deep pit; and the unusual setation of the hind wing.

A new subgenus and species of the braconid parasitoid of the tribe Centistini s. l. (Euphorinae), Centistoides (Palaeoides) magnioculus Belokobylskij, subgen. et sp. nov. , from late Eocene Danish amber are described and illustrated from one female. This is the first time the tribe of euphorine parasitoids is reliably documented in the fossil record. A key to all genera and subgenera of this suprageneric taxonomic group is compiled. The discussion about position of the genus Parasyrrhizus Brues, composition of the tribe Centistini s. l., and the composition of the Danish amber hymenopteran fauna are provided.