Two new species assigned to the genus Myanmarina of the family Myanmarinidae are described and figured from male specimens preserved in Upper Cretaceous ambers from the Hukawng Valley of northern Myanmar. Myanmarina simplex sp. nov. can be distinguished by a small head, 13-segmented antennae, the first flagellomere equal to the second one in length and protibiae with a bifurcated spur. Myanmarina grandis sp. nov. is established based on a large head, 11-segmented antennae, the first flagellomere shorter than the second one and all tibiae with a spur and dorso-apical tooth. In addition, the key to known species of Myanmarina was updated.

One new genus Platyotoma n. gen., and four new species, Platyotoma elongata n. sp., Platyotoma mirabilis n. sp., Pseudoxyela crassa n. sp. and Pseudoxyela lata n. sp., are illustrated and described based on specimens from the Lower Cretaceous Yixian Formation (similar to 125 Ma). The holotypes of blasticotomids, from the Yixian and the Jiulongshan formations in China, are re-examined. Among them, the descriptions of forewing Sc vein morphology in Abrotoma robusta, Synaptotoma limi, and Xyelocerus diaphanus are revised. In addition, a series of new materials of Dahurotoma linearis are reported, allowing a revised description of its forewing Sc. Based on a reevaluation of the forewing Sc morphology within the family, we hypothesize that the presence of Sc stalk is a widespread plesiomorphy in Blasticotomidae. Furthermore, we revised the transformation series of the forewing Sc in Blasticotomidae. These findings not only expand the known fossil species diversity of Blasticotomidae but also provide new evidence on the venation evolution within the Blasticotomidae. (c) 2026 Nanjing Institute of Geology and Palaeontology. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Roproniidae are treated here as a small family of approximately 25 extant species in four genera, apparently closely related to Proctorenyxidae. Clarifying the phylogenetic position of these two lineages within Proctotrupoidea remains a difficult and pressing task requiring broad, integrative analyses. The family is most diverse in eastern Asia, continental China (Shaanxi, Hunan, Fujian, Zhejiang, Guizhou, Sichuan, and one species near the Kachin border), Taiwan, Japan (Honshu, Hokkaido), Kunashir and southern Sakhalin (Townes, 1948; Yasumatsu, 1956, 1958; Lin, 1987; He & Chen, 1991; Yang, 1997; He & Xu, 2015). Three Nearctic species occur in the USA (both coasts) and southern Ontario (Townes, 1948; Porter, 2002). In the Western Palaearctic, two species are known from southern Turkey (Hatay and Karatepe; Madl, 2001). The first European fossil was described from the Paleocene of Menat, France (Garrouste et al., 2016). Named earlier fossil representatives of Roproniidae are otherwise limited to the Cretaceous Kachin amber (Engel & Huang, 2017) and four genera with five species in the extinct subfamily Beipiaosiricinae Hong, 1983 (Middle Jurassic–Early Cretaceous of China and Eastern Siberia) (Rasnitsyn, 1990; Zhang & Zhang, 2001). The present study adds a new roproniid from the Ypresian Fur Formation of the Limfjord region (Northern Jutland, Denmark), constituting the second Cenozoic and youngest European fossil representative of the family.

The Jehol Biota, representing the Early Cretaceous terrestrial ecosystem, has yielded numerous reports of giant insects. Herein, we describe two new scoliid species, including the largest aculeate hymenopteran species †Liaoscolia zhangi gen. et sp. nov., and †Protoscolia obliqua sp. nov., recorded from the Yixian Formation of the Jehol Biota of China. †Liaoscolia zhangi gen. et sp. nov. and †Protoscolia obliqua sp. nov. can be attributed to Scoliidae based on the following characters: pronotum closely appressed to the mesonotum, with a posterior margin deeply U-like incurved, and propodeum with two longitudinal sutures or U-shaped area. We provide an updated key to the Mesozoic Scoliidae and a checklist of all known scoliid fossil species. The new Cretaceous fossil scoliids exemplify that the climate of the Jehol Biota was likely warm and humid.

The first undoubted discovery of a parasitoid ismarid wasp from Cenomanian Kachin amber is presented here. A new genus and species, Thyburia christophi gen. et sp. nov., is described and illustrated, based on a female holotype. The family Ismaridae is synonymised with the family Diapriidae and is considered here as the subfamily Ismarinae. The taxonomy of ismarids and the diagnosis of the subfamily Ismarinae are clarified and discussed.

Falsiformicidae is a poorly known extinct family of aculeate wasps. It is known only as inclusions in various Cretaceous ambers. Brachypterous male Falsiformix pedestris Zhang and Rasnitsyn gen. et sp. nov. is described in the family Falsiformicidae based on a unique fossil from the middle Cretaceous Kachin amber. Occurrence and meaning of the male flightlessness in Hymenoptera is discussed. A combination of the flightless males with flying females occurs when mating takes place shortly after the eclosion, before adults disperse from confined space where they developed. An equally rare even if less exotic strategy with males and females both being flightless depends on the female pedestrian habits rather than on the pre-dispersal mating. Wide spatial (Angara Land, Laurussia Land and Gondwana Land) and narrow temporal distribution (Cenomanian and Turonian ages only) indicate Falsiformicidae as a possibly important stratigraphical indicator. (c) 2024 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Two new species of the family †Falsiformicidae Rasnitsyn, 1975, Siccibythus robustussp. nov. and Siccibythus aristovisp. nov., are described from the mid-Cretaceous Kachin amber based on three well-preserved specimens. The new species belongs to †Siccibythus Cockx & McKellar, 2016, based on the elongate pronotum and fore wing with cells 2+3rm and 3r not enclosed with tubular veins. We summarize the diversity and distribution for all species of †Falsiformicidae and provide a revised key to the family. These new findings enhance the diversity of †Falsiformicidae in Kachin amber.

The fossil beds of the Karabastau Formation in southern Kazakhstan, known as the “Jurassic Lake of Karatau”, represent one of the richest Lagerstätten for Jurassic insects, with more than 800 described species. This year marks the centenary of the first fossil insect descriptions from Karatau, published by A.V. Martynov in 1925. Among the most prominent insect groups from this locality are the Anaxyelidae, a relict family of siricoid woodwasps. Here we report the first occurrence of the subfamily Syntexinae in Karatau, based on a newly discovered and described genus and species, Karasyntexis martynovi gen. et sp. nov., from the Galkino locality. This is only the second Jurassic record of Syntexinae globally. We provide a detailed morphological description of the new taxon and compare it with related syntexine genera. In addition, we reassess the current state of the four historically known fossiliferous localities of the Karabastau Formation (Galkino, Mikhailovka, Karabastau, and Chugurchak), all of which were revisited during a 2025 field expedition. A total of 22 anaxyelid species are now known from Karatau, highlighting the site’s exceptional paleodiversity. Our findings suggest that the true diversity of Karatau’s anaxyelids remains significantly underexplored and underscore the importance of renewed paleontological research in this classic locality.

Here, we report on our restudy of the holotype of Potrerilloxyela menendezi Lara, Rasnitsyn and Zavattieri 2014, focusing on the forewing. We found that the bases of cubitus and the anterior cubitus vein, normally lost in Hymenoptera, are present in Potrerilloxyela menendezi probably as a reversion (atavism). Other cases of reversions are rare in Hymenoptera: this being the oldest known, and the most similar to the groundplan of cubital system in Pterygota. Additionally, we discuss modifications of the cubital system observed in fossil and extant hymenopterans.

Considering taxonomic diversity, extant xyelid sawflies represent a very small subset of the past diversity of the group. A complementary approach to investigate evolutionary changes in this family is to consider ovipositor morphology, an ecologically important organ. New, well-preserved specimens from the Upper Triassic Omin & eacute; locality (Momonoki Formation, Mine Group; Carnian; Japan) and belonging to the dagger Madygellinae, one of the earliest Xyelidae subfamilies, are newly described and assigned to four new species, belonging to three genera (one being new). Two of the specimens expose body parts and wings, providing important information regarding ovipositor morphology. To further appreciate the evolution of this organ, we surveyed both fossil and extant Xyelidae. Extant forms display both extremes of the range of ovipositor types, namely the high aspect ratio "dagger-like" and "needle-like" types (in Xyelinae) and the low aspect ratio "short and wide" type (in Macroxyelinae). All known Triassic representatives display high aspect ratio ovipositor types. In contrast, Middle Jurassic to Lower Cretaceous sawflies show the highest diversity of ovipositor types for the family. Afterwards, the observed range declined and concentrated on the two, very distinct types known nowadays. Decline in ovipositor disparity was not contemporaneous in Xyelinae and Macroxyelinae: specialization occurred during the Jurassic-Cretaceous transition for the Xyelinae, while Macroxyelinae displayed their peak of diversity during the Lower Cretaceous, with a postponed decline. Ovipositor shape transition was probably accompanied with a larval diet change in Macroxyelinae. Ovipositor disparity therefore further contributes depicting extant Xyelidae as a subset on a once more diverse group.

Serphitoids are a group of proctotrupomorphan wasps that, together with mymarommatoids, are characterized by a bipetiolate metasoma and grouped in the clade Bipetiolarida. The internal relationships of Serphitoidea and Mymarommatoidea are still unresolved, and their biology is poorly known. The fossil record of serphitoids is restricted to Cretaceous, ranging from Barremian to Campanian and is limited to specimens in amber so far. The family Serphitidae encompasses more than 30 species within the subfamilies Microserphitinae, Serphitinae, and Supraserphitinae. The subfamily Microserphitinae is well supported, but the distinctions between serphitines and supraserphitines are somewhat ambiguous. We describe Axioserphites obscurus n. gen. n. sp. from the Barremian (Early Cretaceous) Lebanese amber, belonging to the subfamily Supraserphitinae. We comment on the characters defining this subfamily and discuss its systematic validity. (c) 2025 Elsevier B.V. and Nanjing Institute of Geology and Palaeontology, CAS. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

One new genus and five new species of the extinct family Maimetshidae from mid-Cretaceous Kachin amber are described based on five well-preserved specimens as follows: Maimetshasia nova Li, Kopylov and Rasnitsyn, sp. nov.; Maimetshasia engeli Li, Kopylov and Rasnitsyn, sp. nov.; Guyotemaimetsha perrichoti Li, Kopylov and Rasnitsyn, sp. nov.; Guyotemaimetsha ortegablancoi Li, Kopylov and Rasnitsyn, sp. nov.; and Crucimaimetsha nigra Li, Kopylov and Rasnitsyn, sp. nov. A new generic synonymy is proposed: Turgonalus Rasnitsyn, 1990 (=Turgonaliscus Engel, 2016, syn. nov. and = Ahiromaimetsha Perrichot, Azar, Nel and Engel, 2011, syn. nov.); Guyotemaimetsha Perrichot, Nel and Néraudeau, 2004 (=Burmaimetsha Perrichot, 2013, syn. nov.); Afrapia, Rasnitsyn and Brothers, 2009 (=Afromaimetsha, Rasnitsyn and Brothers, 2009, syn. nov.); and Iberomaimetsha nihtmara Ortega-Blanco, Delclòs and Engel, 2011 are transferred to Afrapia, Rasnitsyn and Brothers, 2009. This results in the following new combinations: Turgonalus cooperi, Rasnitsyn and Jarzembowski, 1998, comb. resurr.; Turgonalus najlae (Perrichot, Azar, Nel & Engel, 2011), comb. nov; Afrapia robusta (Rasnitsyn & Brothers, 2009), comb. nov; and Afrapia nihtmara (Ortega-Blanco, Delclòs & Engel, 2011), comb. nov. The occurrence of various genera of Maimetshidae in amber and compression fossil and the morphological differences of the forewings in all the fossil species are provided, which highlights a high level of genus-level diversity among Mesozoic maimetshids. The key to genera was updated.

Three new species—Enneoxyela aculeata sp. nov., Enneoxyela eucalla sp. nov., and Hemixyela elongata gen. et sp. nov.—are described and illustrated from the Lower Cretaceous Yixian Formation at Huangbanjigou, Liaoning Province, China. Meanwhile, two new genera are established by the species previously described after re-examination, Tugnuxyela gen. nov. based on T. tugnuica comb. nov. (Rasnitsyn, 1982), from the Lower Jurassic of Transbaikalian in Russia, and Junfengixyela gen. nov. based on J. cenozoica comb. nov. (Zhang, 1989) from the Miocene of Shandong in E. China. This is the first occurrence of the tribe Xyelini in the Cretaceous of China. A male specimen is described for the first time in Mesozoic Xyelini; it is found sufficiently similar to the known (Cenozoic) males of the tribe, including the genitalia twisted for 180°. Keys to the genera of Xyelini and to the species of Enneoxyela are provided.

Euthygramma storozhenkoi Rasnitsyn, sp. nov. is described in the family Caloneuridae (order Caloneurodea) based on the unique fossil from the uppermost Permian Kulchumovo Fm. in the Orenburg Region of Russia. The new record is the latest for the family and for the entire order.

The study of the invertebrate fauna of the lower Albian Jinju Formation (Republic of Korea) has experienced renewed interest over the past decade, with numerous new extinct species described each year. Among the various insect orders, Hymenoptera are relatively abundant in the assemblage, with many taxa being discovered and formally described on a regular basis. Within this group, Symphyta are particularly well represented, with series of specimens of varying preservation quality being documented. These newly discovered specimens frequently represent new species belonging to genera already known from subcontemporaneous deposits in China, Mongolia, and Russia, supporting the idea of a relatively homogeneous Early Cretaceous Asian entomofauna. Here, we further corroborate this pattern by describing a new species of Ghilarellinae assigned to the Asian genus Ghilarella, Ghilarella jinjuensis sp. nov. In addition, we describe a second species of the previously monotypic genus Meiaghilarella, which was formerly known only from Spain. The new species, Meiaghilarella stanislawlemi sp. nov., substantially extends the geographic range of the genus during the Albian, from apreviously restricted occurrence in Spain to a trans-Laurasian distribution.

Wing venation pattern is particularly important in the taxonomy and classification of insects, especially for fossil material. There are recognized transformation series that apparently often represent a mainstream in the evolutionary trend of the wing venation of Hymenoptera. One notable instance is the gradual reduction of the subcosta veins from multiple branches to their total absence. Herein, we place four new genera and six new species in the family Blasticotomidae (=Xyelotomidae) of Hymenoptera. They are Xyelocerus abruptus sp. nov., Liberitoma tenella gen et sp. nov., Liberitoma compta sp. nov., Liberitoma incompleta sp. nov., Aduantoma insolita gen. et sp. nov., and Apertoma gen. nov. from the Middle Jurassic of China, and Enspeletoma oligocaenica gen. et sp. nov. from the Upper Oligocene of Germany. The newly discovered species of Liberitoma from China possessed a supernumerary hind branch of vein Sc in its forewing, which has apparently never been recorded before in other hymenopterans, and the unique venation pattern of Aduantoma suggests the possibility of two additional steps of vein Sc transformation before its complete loss. Based on the new findings, Blasticotomidae are proposed to be divided into four subfamilies: Blasticotominae Thomson 1871, Dahurotominae subfam. nov., Pseudoxyelocerinae subfam. nov., and Undatominae subfam. nov.

The composition of the order Miomoptera is considered at the family level, and the system of the family Permosialidae is revised. Keys are provided to families of the order and to genera and species of the family Permosialidae, with synonymies and unified diagnoses of the genera and species of Permosialidae. The composition of the family is shown to remain uniform through its entire time interval, with the type genus always prevalent, and the only one recorded at its start (late Kungurian) and finish (Triassic). The geographical distribution of Permosialidae is noteworthy: widespread over Angarida and confined to that region except for a unique record from Australia.

Insects have evolved complex sensory systems that are important for feeding, defence and reproduction. Parasitoid wasps often spend much time and effort in searching for concealed hosts with the help of specialized sensilla. However, the early evolution of such behaviour and sensilla is poorly known. We describe two fossil female wasps, †Tichostephanus kachinensis sp. nov. and †Tichostephanus longus sp. nov., from mid-Cretaceous Kachin amber. Phylogenetic analyses based on morphological data retrieved †Tichostephanus as deeply nested within Evanioidea and closely related to extant Gasteruptiidae and Evaniidae. Both of these Cretaceous wasps possess features, e.g. coronal tubercles and flexible ovipositor sheaths, that indicate that they might have laid eggs in wood where their larvae possibly parasitized insect larvae. They have a peculiar and unique 'bottle brush' of sensilla close to the apex of their ovipositor sheaths, which has not been observed in any extant parasitoid wasps. These sensilla comprise many regularly arranged plate-shaped setae, attached in relatively large sockets and with rows of longitudinal ridges. Such specialized sensilla perhaps served to enhance the ability to detect hosts inside wood.

One new species, Ghilarella elegantula sp. nov., in the family Sepulcidae is described and illustrated based on a well-preserved compression fossil specimen from the Lower Cretaceous Yixian Formation of northeastern China. The new species is characterized by having a large body size; forewing with costal area obviously narrowed basally, Sc and 2r-m absent, 1-Rs short, cell 1mcu large; and ovipositor elongated. In addition, Ghilarella cf. mercurialis is given its own name Ghilarella kopylovi as the new species in Ghilarella. An updated key for the known species of Ghilarella is provided. Moreover, a well-preserved ovipositor is reported for the first time in the subfamily Ghilarellinae. The two new species not only improve our understanding of Ghilarella by adding more morphological features, but also expand the distribution ranges of Ghilarellinae fossil records.

One new genus and two new species, Hemisyntexis lepida gen. et sp. nov., Eosyntexis conflata sp. nov., and new material of Parasyntexis khasurtensis Kopylov, 2019 are respectively described and illustrated based on three well-preserved compression fossils from the Lower Cretaceous Yixian Formation of northeastern China. Eosyntexis conflata sp. nov., placed in the genus Eosyntexis Rasnitsyn, together with H. lepida, belongs to the subfamily Syntexinae of Anaxyelidae. The new species provide important morphological characters to enhance our understanding of the subfamily Syntexinae, and to revise the diagnostic characters of Eosyntexis as well. Moreover, we carried out a comprehensive survey of all currently published extant and extinct species of Anaxyelidae to gain a better understanding of the trend of change for the forewing and body length. Furthermore, we formally documented that the Anaxyelidae had four different color patterns for the wings simultaneously in the Jehol Biota of the Lower Cretaceous.