mid-Cretaceous Myanmar Research Articles

A new wasp genus of Cirrosphecidae (Hymenoptera: Apoidea) from mid-Cretaceous amber of northern Myanmar

A new apoid genus with one new species Heterosphex wuni Li, Rosa, Melo and Shih gen. et sp. nov. is described in Cirrosphecidae based on a male wasp from mid-Cretaceous Myanmar (Burmese) amber. The new taxon is placed in Cirrosphecidae due to its swollen, ring-like metanotum with anterior margin surrounding the scutellum; omaular sulcus and omaular carina absent; propodeum short, with rounded edges and distinctly slanted; metapostnotum extending as a narrow triangle onto posterior surface of propodeum; notaulus not indicated; claws with subapical teeth; and mid tibia with one spur. A key for genera and species of Cirrosphecidae is provided. Up to date, all taxa in Cirrosphecidae are known only from mid-Cretaceous Myanmar amber.

New wood soldier flies from mid-Cretaceous Myanmar amber (Diptera, Stratiomyomorpha, Xylomyidae)

Two new wood soldier flies, Clemoxyla aculeolata gen. et sp. nov. and Archeoxyla gigantea gen. et sp. nov., are described from mid-Cretaceous Myanmar (Burmese) amber. Clemoxyla gen. nov. is most characteristic of the broadened cell d and presence of short M1+2 stem after the cell d. The apical palpus of Archeoxyla gen. nov. is obviously expanded that is distinct from other known fossil xylomyid genera. Based on the analysis of key features of body and venation, the genus Cretarthropeina Solórzano Kraemer and Cumming, 2019 is transferred from Xylomyidae to Stratiomyidae as the sixth soldier fly from mid-Cretaceous Myanmar amber. In addition, a key to the genera of all known fossil and extant xylomyids is provided.

Geometric Morphometric Analysis of two genera confirm three new wasps from the mid-Cretaceous of Myanmar (Hymenoptera: Aulacidae)

Three new species, Exilaulacus advenus sp. nov., Exilaulacus eximius sp. nov. and Electrofoenops exaltatus sp. nov. in two genera of Aulacidae, are described and figured based on three well-preserved specimens from the mid-Cretaceous Myanmar (Burmese) amber. Forewings of four described fossil species of Aulacidae and the three new species are studied by using the Geometric Morphometric Analyses (GMA) to further confirm their taxonomic classifications.

New specimens from Mid-Cretaceous Myanmar amber illuminate the phylogenetic placement of Lagonomegopidae (Arachnida: Araneae)

Abstract New lagonomegopid spiders are described from Mid-Cretaceous Myanmar (Burmese) amber. Two new genera and species based on single specimens, Scopomegops fax gen. & sp. nov. and Hiatomegops spinalis gen. & sp. nov. are described. Two specimens belonging to Lineaburmops beigeli are further described. Additionally, after re-examining the holotype of Odontomegops titan, a detailed description of its basal ventral abdomen is added here. A phylogenetic analysis was performed to investigate the phylogenetic placement of Lagonomegopidae. A matrix of 79 morphological characters, scored for six lagonomegopid taxa and 26 non-lagonomegopid taxa, was analysed through parsimony and Bayesian phylogenetic inference. Our results recover extant Palpimanoidea as a monophyletic group and partly suggest that Lagonomegopidae is the sister-group to extant Palpimanoidea. The external sexual organs, retrolateral tibial apophysis on the male palp and tracheal spiracle in lagonomegopids are discussed.

New species of Hybristodryinus from mid-Cretaceous Myanmar amber (Hymenoptera, Dryinidae)

A new species of the genus Hybristodryinus Engel, 2005, Hybristodryinus viriosus sp. nov., is described from the mid-Cretaceous Myanmar (Burmese) amber based on a well-preserved female specimen. The keys to fossil species of Hybristodryinus is modified. The new species is most similar to Hybristodryinus mon Perkovsky, Olmi, Müller and Martynova, 2019, but the distance between inner edge of the lateral ocelli is much longer than the distance from the posterior edge of the lateral ocellus to the occipital carina, and which is also much longer than the distance between the inner edge of a lateral ocellus and the median ocellus. This new finding not only broadens the diversity of Dryinidae, but also provides important morphological characters, especially the well-preserved details of the chelate protarsus used for capturing hosts, to enhance our understanding of Hybristodryinus.

New amber record of Braconidae (Insecta: Hymenoptera) from the mid-Cretaceous of Myanmar

Protorhyssalinae is an extinct, Cretaceous-only subfamily of braconid wasps hitherto comprising 7 genera and 7 species in its widest acceptance. A new genus Burmabracon gen. nov. with two new species, B. gracilens sp. nov. and B. grossus sp. nov. from the mid-Cretaceous Myanmar (Burmese) amber, are described and assigned to Protorhyssalinae, based on the following characters: head orthognathous and almost certainly cyclostome, antenna with more than 20 antennomeres, notauli complete, forewing with 2m-cu absent and hind wing with 1r-m and Cu present. The Mesozoic fossil record of the Braconidae suggests that the family originated in or before the Early Cretaceous.

Vespids from the mid-Cretaceous with club-shaped antennae provide new evidence about the intrafamiliar relationships of Vespidae

Abstract Three new species of wasps (Hymenoptera: Vespidae) from mid-Cretaceous Myanmar (Burmese) amber, with club-shaped antennae, are assigned to Archaeovespa gen. nov. and provide morphological information for new phylogenetic analyses of Vespidae. Phylogenetic results suggest that Archaeovespa has more affinities with Masarinae than with Protovespinae and, along with Masarinae, composes the sister clade to Polistinae, Eumeninae, Vespinae and Stenogastrinae. New findings indicate that the antennal morphologies of Vespidae diversified significantly during or before the mid-Cretaceous.

Cretaceous mantid lacewings with specialized raptorial forelegs illuminate modification of prey capture (Insecta: Neuroptera)

AbstractThe Mantispidae (Neuroptera), commonly known as mantid lacewings or mantispids, are characterized by raptorial forelegs used by adults for predation. They have a fossil history extending to the Early Jurassic. During the past 180 Myr, the lineage has undergone significant evolutionary transformation, exhibiting an elevated diversity in morphology yet retaining the same overall ground plan. Although raptorial foreleg morphology and capture behaviour are well documented in extant insects, they are poorly known for premodern lineages, attributable to the scarcity and poor preservation of fossils. Here, we report two new genera and species of Mantispidae from mid-Cretaceous Myanmar (Burmese) amber. Both taxa have highly specialized raptorial forelegs and highlight modification of capture strategy in Cretaceous Mantispidae. The foreleg of both species has one major spine that is the same length as the foretibia on the ventral surface of the forefemur, which faces the foretibia with a row of robust setae. The two new amber mantid lacewings provide structural and functional indications that represent an extinct mode of capture strategy. The new findings reveal the presence of a geochronologically rapid diversification of Mantispidae during the Early Cretaceous, thereby illuminating the varied morphologies involved in prey-capture strategies integral to the early evolution of mantispids.

The first plumalexiid wasp (Hymenoptera: Chrysidoidea, Plumalexiidae) from the mid-Cretaceous Burmese amber

A new species of plumalexiid wasp, Plumalexius ohmkuhnlei sp. nov., is described from the mid-Cretaceous Myanmar (Burmese) amber, based on a single male specimen. It is compared with the only other known plumalexiid, Plumalexius rasnitsyni Brothers, from the Turonian New-Jersey amber, and provides additional information confirming the relatively basal status of the family within Chrysidoidea.

New vespids from mid-Cretaceous amber of northern Myanmar provide evidence for the phylogenetic relationships of Priorvespinae (Hymenoptera: Vespidae)

Two new species of well-preserved female wasps, Alivespa hirta gen. et sp. nov. and A. colossa sp. nov. in the extinct subfamily Priorvespinae of Vespidae, are described and figured from the mid-Cretaceous Myanmar (Burmese) amber. Phylogenetic results based on morphological characters indicate that Alivespa gen. nov, is attributed to the subfamily of Priorvespinae. The results confirm that Priorvespinae is the sister group of non-Euparagiinae. In addition, a tibia spur with a row of setae on the foreleg of Alivespa hirta gen. et sp. nov. is a unique feature for Vespidae because tibia spur with a row of setae on the foreleg is not present in all extant or fossil vespids documented up to now.

A New Genus of Crickets (Orthoptera: Gryllidae) in Mid-Cretaceous Myanmar Amber

Crickets (Orthoptera: Grylloidea) are a highly diverse and successful group that due to their chirping are often heard more often than they are seen. Their omnivorous diet allows them to exist in a variety of terrestrial habitats around the world. In some environments, cricket populations can build up and become plagues, resulting in significant damage to seedling crops. A new genus and species of cricket, Pherodactylus micromorphus gen. et sp. nov. (Orthoptera: Gryllidae) is described from mid-Cretaceous Myanmar amber. The new genus is characterized by the following features: head without prominent bristles, pronotum longer than wide, middle of pronotal disk with two distinct large dark “eyespots”, fore leg robust and 3 apical spurs arranged on inner side of fore leg tibia. Shed portions of a lizard skin adjacent to the specimen reveal possible evidence of attempted predation.

A New Genus of Crickets (Orthoptera: Gryllidae) in Mid-Cretaceous Myanmar Amber

Crickets (Orthoptera: Grylloidea) are a highly diverse and successful group that due to their chirping are often heard more often than they are seen. Their omnivorous diet allows them to exist in a variety of terrestrial habitats around the world. In some environments, cricket populations can build up and become plagues, resulting in significant damage to seedling crops. A new genus and species of cricket, Pherodactylus micromorphus gen. et sp. nov. (Orthoptera: Gryllidae) is described from mid-Cretaceous Myanmar amber. The new genus is characterized by the following features: head without prominent bristles, pronotum longer than wide, middle of pronotal disk with two distinct large dark “eyespots”, fore leg robust and 3 apical spurs arranged on inner side of fore leg tibia. Shed portions of a lizard skin adjacent to the specimen reveal possible evidence of attempted predation.

A new anaxyelid sawfly (Insecta, Hymenoptera, Siricoidea) in mid-Cretaceous Myanmar amber

A new sawfly, Sclerosyntexis hirsuta gen. et sp. nov., in the subfamily Syntexinae of the Anaxyelidae is described from the mid-Cretaceous Myanmar (Burmese) amber. The new taxa is established primarily based on the following characters, i.e. body fusiform with a large head; antenna with pedicel almost twice as long as the first flagellomere; mesonotum with longitudinal, scuto-scutellar sulci; forewing with pterostigma completely sclerotized; Sc and 1r-rs absent; hind wing with cell r open distally; 1r-m longer than 1-Rs and 1-M; m-cu lost; free ending of Cu lost, 1-Cu and cu-a straight. Sclerosyntexis hirsuta gen. et sp. nov. has a short and oval body shape, which is unique in Anaxyelidae, since the bodies of most xylophagous anaxyelids are long and subcylindrical. The finding is the first record of Anaxyelidae in Myanmar amber hitherto, providing important morphological characters to enhance our understanding of the Anaxyelidae.

Geometric morphometric analysis of Ichneumonidae (Hymenoptera: Apocrita) with two new Mesozoic taxa from Myanmar and China

A new genus and species of Labenopimplinae (Ichneumonidae), Heteropimpla megista Li, Shih, Kopylov & Ren gen. et sp. nov., is erected based on a specimen in mid-Cretaceous Myanmar (Burmese) amber. A key to genera of Labenopimplinae is provided. In addition, a new species, Amplicella abbreviata Li, Shih, Kopylov & Ren (Tanychorinae) from the Lower Cretaceous Yixian Formation is described. Geometric morphometric analysis (GMA) was applied to study forewing venation of 24 Cretaceous species of Ichneumonidae and the results are presented for the first time. The GMA results not only confirm the taxonomic position of new taxa and relationships among these genera consistent with subfamily classifications, but also clarify the methodological differences between classical taxonomy and the GMA.http://zoobank.org/urn:lsid:zoobank.org:pub:DC98459D-45C1-4B78-B59E-F32787B787F1

New insects feeding on dinosaur feathers in mid-Cretaceous amber

Due to a lack of Mesozoic fossil records, the origins and early evolution of feather-feeding behaviors by insects are obscure. Here, we report ten nymph specimens of a new lineage of insect, Mesophthirus engeli gen et. sp. nov. within Mesophthiridae fam. nov. from the mid-Cretaceous (ca. 100 Mya) Myanmar (Burmese) amber. This new insect clade shows a series of ectoparasitic morphological characters such as tiny wingless body, head with strong chewing mouthparts, robust and short antennae having long setae, legs with only one single tarsal claw associated with two additional long setae, etc. Most significantly, these insects are preserved with partially damaged dinosaur feathers, the damage of which was probably made by these insects’ integument-feeding behaviors. This finding demonstrates that feather-feeding behaviors of insects originated at least in mid-Cretaceous, accompanying the radiation of feathered dinosaurs including early birds.

New sawflies from the mid-Cretaceous Myanmar amber (Insecta: Hymenoptera: Syspastoxyelidae)

ABSTRACT Many insects have been described from the mid-Cretaceous Myanmar (Burmese) amber in recent years, including about 50 families of wasps. However, only two species of sawfly, Syspastoxyela rhaphidia and Striaexyela longicornis (Syspastoxyelidae), have been described in Myanmar amber, in contrast to more than 100 species of sawflies from the Mesozoic of Kazakhstan and China. Herein, we describe three new taxa of sawflies, Deltoxyela engeli gen. et sp. nov., Syspastoxyela pinguis sp. nov. and Syspastoxyela simpla sp. nov., based on six amber pieces with 21 specimens of sawflies from the mid-Cretaceous Myanmar amber. The new findings suggest that syspastoxyelids were speciose and prosperous in the ecosystem, even though only one family of sawflies, Syspastoxyelidae, has been reported hitherto.

Two new lagonomegopid spiders (Arachnida: Araneae) from the mid-Cretaceous of Northern Myanmar, with comments on the superfamilial placement of Lagonomegopidae

Two new lagonomegopid spiders, Odontomegops titan gen. et sp. nov. and Lagonomegopidae indet., are described from mid-Cretaceous Myanmar (Burmese) amber. Odontomegops titan gen. et sp. nov. differs from other lagonomegopids in its large body size and the presence of true teeth on the cheliceral retromargin. The two lagonomegopids described here also clarify the presence of feathery setae in this family. The superfamilial placement of Lagonomegopidae in Palpimanoidea is discussed, based on the true teeth and feathery setae.

Application of geometric morphometric analyses to confirm three new wasps of Evaniidae (Hymenoptera: Evanioidea) from mid-Cretaceous Myanmar amber

Evaniidae, commonly called ‘ensign wasps’ or ‘hatchet wasps’, comprise more than 21 described extant genera with over 449 species and an additional 17 extinct genera including 35 species from the Cretaceous and Paleogene deposits. Herein, Burmaevania gen. nov. with two new species B. brevis sp. nov and B. aequalis sp. nov, and a new species of Newjersevania rasnitsyni sp. nov. are described based on three well-preserved specimens from the mid-Cretaceous Myanmar (Burmese) amber. Besides morphological comparisons, forewings of nine described genera of Evaniidae and the three new species are studied by using the Geometric Morphometric Analyses (GMA) to confirm their state.urn:lsid:zoobank.org:pub:DBE8E565-5671-4B5A-93F2-8AEC6DA22A50.

Termite colonies from mid-Cretaceous Myanmar demonstrate their early eusocial lifestyle in damp wood.

Insect eusociality is characterized by cooperative brood care, reproductive division of labour and multiple generations of adults within a colony. The morphological specializations of the different termite castes from Burmese amber were recently reported, indicating the termites possessed advanced sociality in the mid-Cretaceous. Unfortunately, all the reported Cretaceous termites are individually preserved, which does not cover the behaviours of the cooperative brood care and multiple generations of adults in the nests of the Cretaceous termites. Herein, we report three eusocial aggregations from colonies of the oldest known Stolotermitidae, Cosmotermesgen. nov., in 100 Ma mid-Cretaceous Burmese amber. One large aggregation, comprising 8 soldiers, 56 workers/pseudergates and 25 immatures of different instars, additionally presents the behaviours of cooperative brood care and overlapping generations. Furthermore, taphonomic evidence indicates Cosmotermes most probably dwelled in damp/rotting wood, which provides a broader horizon of the early societies and ecology of the eusocial Cosmotermes.

Two new rare wasps (Hymenoptera: Apocrita: Panguidae and Burmusculidae) from mid-Cretaceous amber of Northern Myanmar

A new superfamily Panguoidea superfam. nov. is erected based on one new family, Panguidae fam. nov., with one new genus and species, Pangu yuangu gen. et sp. nov. In addition, one new species, Burmusculus magnus sp. nov. of Burmusculidae, is also described. Both of these two type specimens are from mid-Cretaceous Myanmar (Burmese) amber. A key to species of Burmusculidae is provided. The new family Panguidae displays a contradictory array of features to further supplement the taxonomic and morphological characters of Apocrita.(urn:lsid:zoobank.org:pub:42BB16DA-1F8E-40F1-ADA9-0ECF321B8355)