Myanmar Amber Research Articles

A New Genus and Species of Dinoderinae Subfamily (Coleoptera: Bostrichidae) from Mid-Cretaceous Kachin Amber of Northern Myanmar

A New Genus and Species of Dinoderinae Subfamily (Coleoptera: Bostrichidae) from Mid-Cretaceous Kachin Amber of Northern Myanmar

Investigation of Cretodorus (Hemiptera: Fulgoromorpha: Mimarachnidae) based on new adult and nymph fossils from mid-Cretaceous Myanmar amber

Here we report a new species, Cretodorus lijuanae sp. nov., of extinct Mimarachnidae from mid-Cretaceous amber of northern Myanmar. C. lijuanae sp. nov. was described based on one adult and three nymphal fossils. The new adult specimen exhibits the diagnostic features of Cretodorus and possesses a unique number and arrangement of sensory pits in the pronotum: nine sensory pits on one side, with five sensory pits between median and pronotal carinae and four sensory pits between lateral carina and margin, which is consistent in the nymphs. We also conduct morphometric analyses of forewings of all known species of Cretodorus, demonstrating that morphometrics are effectively discriminative for identifying Cretodorus fossils featuring few longitudinal veins and minimal differences in venation. Additionally, we report the nymphal fossils of Mimarachnidae for the first time. Three nymphal fossils, preserved in the same piece of amber alongside the adult specimen, exhibit the same nodule pattern on the thoracic notum in dorsal view, suggesting a feature linking adult and nymph of Mimarachnidae. These new specimens show morphological characteristics of the different developmental stages of C. lijuanae sp. nov., increasing the diversity of the Mimarachnidae in mid-Cretaceous amber from Myanmar. The preservation of three nymphs of the same age with an adult in the same piece of amber likely indicates aggregation behaviour in Mimarachnidae.

A new genus of beaded lacewings (Neuroptera: Berothidae) from the mid-Cretaceous Myanmar amber

A new genus of beaded lacewings (Neuroptera: Berothidae) from the mid-Cretaceous Myanmar amber

The oldest fossil record of Philopotinae (Diptera: Acroceridae) from the mid-Cretaceous amber of Northern Myanmar

A new genus and species of Acroceridae Leach, 1815, Burmophilopota wintertoni gen. et sp. nov., is identified from mid-Cretaceous Burmese amber, representing the oldest member of Philopotinae Schiner 1868. Based on morphological comparisons, Burmophilopota wintertoni gen. et sp. nov. most likely represents a stem group of the Philopotinae. The new material with well-preserved details of mouthparts and complete wing venation suggests that the new species could possibly be a pollinator for the angiosperms. This finding enhances our understanding of early origin and evolution of pollinating flies during the Mesozoic period.

New Genus and Species of Webspinners (Insecta: Embioptera) from the Mid-Cretaceous of Myanmar with a Catalog of Fossil Members.

One new genus (Ocrognethoda gen. nov.) and three new species of webspinners (Ocrognethoda olivea gen. et sp. nov., Gnethoda lata sp. nov. and Parasorellembia hamata sp. nov.) are described from the Upper Cretaceous of Myanmar amber. Ocrognethoda olivea gen. et sp. nov. and Gnethoda lata sp. nov. are attributed to the family Clothodidae due to their simplified and symmetrical male terminalia, in which the tenth tergum is undivided. Parasorellembia hamata sp. nov. is classified in the family Scelembiidae by a specialized abdominal apex: fused cerci, a broad right hemitergite of the tenth abdominal tergite, and ocelli presence. Moreover, based on the discovery of new genus and species, the male terminalia of Clothodidae and Sorellembiinae are briefly discussed.

Characters of a new species of the Cretaceous genus †Loeblitoides affirm affinities to the extant ‘Syndicus group’ of Stenichnini (Coleoptera: Staphylinidae: Scydmaeninae)

A new species of Cenomanian Stenichnini is described, based on an inclusion in Myanmar amber: †Loeblitoides latus sp. nov. As a close relationship between †Loeblitoides and the extant genera Syndicus Motschulsky, Loeblites Franz, and Horaeomorphus Schaufuss was postulated, we used 3D visualization techniques based on micro-computed tomography to search for otherwise impossible to observe morphological details and find arguments supporting this hypothesis. A novel structure, a pair of basal elytral foveae connected in a peculiar way, found in †L. latus, indeed supports the previous views, as it is unique for the extant ‘Syndicus group’. The diagnosis of †Loeblitoides is emended to include new findings.

Two interesting new genera of kalligrammatids (Insecta: Neuroptera) from Upper Cretaceous Myanmar amber

Two interesting new genera of kalligrammatids (Insecta: Neuroptera) from Upper Cretaceous Myanmar amber

New Genera and Species of Trigonidiidae (Orthoptera: Grylloidea) from the Mid-Cretaceous of Myanmar with a Redescription of Birmaninemobius hirsutus.

The abundance of insects in Burmese amber illustrates a highly diverse insect community from the mid-Cretaceous period; yet, records of crickets (Grylloidea) are notably scarce. In this study, we describe two new genera with three new species, Palaeotrigonidium concavoculus gen. et sp. nov., Palaeotrigonidium defectivus sp. nov., and Tricalcaratus longilineus gen. et sp. nov., based on three specimens collected in north Myanmar. These new species can be placed within the Trigonidiidae (Orthoptera: Grylloidea) by their triangular head, compound eyes that protrude in dorsal view, and a body entirely covered with robust setae, particularly noticeable in the head and pronotum; however, subfamily assignments are not possible. Another known species, Birmaninemobius hirsutus, Xu et al., 2020, from Myanmar amber is redescribed based on a new specimen and a recheck of the holotype.

A new genus and species of Nabinae (Heteroptera: Cimicomorpha: Nabidae) from mid-Cretaceous Burmese amber

A remarkable new genus and species, Mecocollaris simplipodus gen. et sp. nov. is described from mid-Cretaceous amber. It is the second fossil record of Nabinae from Myanmar amber. The new species is distinguished from other nabids based on labial segment Ⅲ longer than the combination of segments I, Ⅱ and Ⅳ, hind tibia without clear row of setae corresponding to stiff setae associated with the Ekblom’s organ. By comparing extant species and fossil records of Nabidae, the evolution of the Ekblom’s organ of nabids is discussed.

One New Genus and Four New Species of Beaded Lacewings (Neuroptera: Berothidae) from Upper Cretaceous Myanmar Amber.

In recent years, as more and more fossil species of berothids from Myanmar have been reported, the species and morphological diversity of Berothidae continues to increase. Herein, one new species of Berothidae, Aggregataberotha paucipunctata sp. nov., and one new genus, Sejunctaberotha gen. nov., with three new species (Sejunctaberotha sphaerica gen. et sp. nov., Sejunctaberotha tenuis gen. et sp. nov. and Sejunctaberotha transversa gen. et sp. nov.) are described from mid-Cretaceous Myanmar amber. A. paucipunctata sp. nov. is assigned to Aggregataberotha Wang, Huang & Wang, 2022, based on the characteristics of the similar female terminalia and wing venation, but can be different from A. punctate regarding the pale pterostigma and a few detailed features of wing venation. Additionally, representatives of Sejunctaberotha gen. nov. are remarkably different from the representatives of the other genera within Berothidae in the configuration of wing venation. For example, Sejunctaberotha gen. nov. has simple subcostal veinlets, obviously free Sc and RA at the apex present both in fore- and hindwings, a single ra-rp crossvein connecting the RA with RP3, a single rp-m crossvein locating before the origin of the MP, a simple CuP and no gradate veins. Interestingly, in one of the specimens of Sejunctaberotha gen. nov., a pair of spherical bulges was found at the end of the antennae. The new genus Sejunctaberotha gen. nov. suggests that Berothidae had a higher potential diversification during the Mesozoic Era.

Complete checklist of Burmese (Myanmar) amber taxa 2023

This is a list of all known taxa described or recorded from Burmese (Myanmar) amber from the published literature up to the end of 2023. Data from previously published checklists have been merged, the higher taxonomy has been updated and the total numbers of taxa have been checked and corrected. A total of 2,805 species have been described or recorded from Cretaceous amber of Myanmar.

A New Fossil of Cystodium (Cystodiaceae) from the mid-Cretaceous Myanmar amber

The only known fossil of Cystodium (Cystodiaceae) is C. sorbifolioides from mid-Cretaceous Myanmar amber. Here we describe a new fossil species of Cystodium, C. parasorbifolium, also from amber collected in Myanmar. This new species belongs to Cystodium based on pinnate fertile lamina segments, terminal sori protected by a reflexed lobe of the lamina (outer or false indusium), free veins, vertical annuli interrupted at the stalk, trilete spores, and striate perines. It differs from C. sorbifolioides by reflexed ovate-conical indusia and spores with clear striate perines. This new fossil species suggests that Cystodium was more diverse in the forests of Myanmar during the Cretaceous.

New fossil caddisflies (Trichoptera, Dysoneuridae) from the Lower Cretaceous of Inner Mongolia, China

A new caddisfly species, Khasurtia apertalocularis sp. nov., and a Dysoneuridae gen. indet. sp., are described and illustrated, and Utania defecta Sukatsheva, 1982 is redescribed, based on 13 fossil specimens from the Lower Cretaceous Yixian Formation of Inner Mongolia, China. This is the first report of the family Dysoneuridae in China, enhancing the geographical distribution of this family and providing reference to the paleogeography. New specimens show that the species previously classified as Dysoneuridae from the compression fossils and Myanmar amber belong to different families based on the characters of wing, ocelli and antennae; and support that the caddisflies in Myanmar amber be elevated to two families, Burmapsychidae and Cretapsychidae.

Mesozoic evolution of cicadas and their origins of vocalization and root feeding

Extant cicada (Hemiptera: Cicadoidea) includes widely distributed Cicadidae and relictual Tettigarctidae, with fossils ascribed to these two groups based on several distinct, minimally varying morphological differences that define their extant counterparts. However, directly assigning Mesozoic fossils to modern taxa may overlook the role of unique and transitional features provided by fossils in tracking their early evolutionary paths. Here, based on adult and nymphal fossils from mid-Cretaceous Kachin amber of Myanmar, we explore the phylogenetic relationships and morphological disparities of fossil and extant cicadoids. Our results suggest that Cicadidae and Tettigarctidae might have diverged at or by the Middle Jurassic, with morphological evolution possibly shaped by host plant changes. The discovery of tymbal structures and anatomical analysis of adult fossils indicate that mid-Cretaceous cicadas were silent as modern Tettigarctidae or could have produced faint tymbal-related sounds. The discovery of final-instar nymphal and exuviae cicadoid fossils with fossorial forelegs and piercing-sucking mouthparts indicates that they had most likely adopted a subterranean lifestyle by the mid-Cretaceous, occupying the ecological niche of underground feeding on root. Our study traces the morphological, behavioral, and ecological evolution of Cicadoidea from the Mesozoic, emphasizing their adaptive traits and interactions with their living environments.

Preheterobathmia gen. nov. – a new non-glossatan taxon from Myanmar amber tentatively assigned to Heterobathmiidae (Insecta, Lepidoptera)

The description of a new fossil taxon Preheterobathmia grimaldiigen. nov. et sp. nov. is provided from Myanmar amber. The new taxon is tentatively assigned to the extant family Heterobathmiidae based on corresponding architecture of the female genitalia. It displays an interesting mixture of plesiomorphies and apomorphies, which are discussed in a comparison between Preheterobathmiagen. nov. and Heterobathmia. The fossil provides new information to the phylogeny and historical biogeography of ancestral Lepidoptera.

Two new species and new material of the family Evaniidae (Hymenoptera: Evanioidea) from the mid-Cretaceous amber of Northern Myanmar

Two new species, Sorellevania rara Li, Shih & Ren, sp. nov. and Iberoevania nova Li, Shih & Ren, sp. nov., and a new specimen of Cretevania bechlyi Jennings, Krogmann & Mew, 2013 are described and illustrated respectively from two male and one female specimens preserved in the mid-Cretaceous Kachin amber. Sorellevania rara sp. nov. is the third species of the genus Sorellevania Engel, 2006. The placement of the new specimen in the latter genus is supported by its small body size, its elbowed antenna, and its forewing venation (e.g., the shape of the medial cells). Iberoevania nova sp. nov. is assigned to Iberoevania based on its forewing with five enclosed cells, the crossveins 2r-m, and 2m-cu absent while 1rs-m is present, and its long petiole (about half the length of the gaster). A map of the deposits yielding Evaniidae during the Cretaceous and a histogram of Evaniidae species and genus diversity during the Cretaceous and Cenozoic are provided.

The stridulatory organ in Opetiidae and Phoridae (Diptera) and phylogenetic implications for the evolution of higher flies

Stridulatory sound-making organs evolved in a group of flies—the family Phoridae—by modifications of the microstructure of foreleg segments present in the shared ancestor of the clade (Phoridae + Opetiidae). The opetiids are the only group amongst the lower Cyclorrhapha in which plausible homologous structures could be found, though in a less derived condition. On the forefemur of Opetia there are numerous elongate, flattened microtrichia that in basal phorids are organized into a curved linear group (the scraper) which are scraped against a curved, ridged carina on the forecoxa (the file). The file was possibly derived from an extremely unusual set of three setae that have transverse sculpturing and sockets that limit lateral motion, and which are distributed across the opetiid forecoxa. In some phorid lineages, these setae seem to be fused into the forecoxa forming the linear ridged surface against which the scraper on the forefemur could be moved. The relationship between opetiids and phorids dates back to the Cretaceous, and this pattern of file and scraper can be clearly seen in some 100 mya Myanmar amber phorid fly fossils. These structures shared between opetiids and phorids suggest that these two families may be sister groups amongst the Platypezoidea. Different modifications of the forelegs of other higher flies may have similar roles.

Fossils in Myanmar amber demonstrate the diversity of anti-predator strategies of Cretaceous holometabolan insect larvae

Holometabolan larvae are a major part of the animal biomass and an important food source for many animals. Many larvae evolved anti-predator strategies and some of these can even be recognized in fossils. A Lagerstätte known for well-preserved holometabolan larvae is the approximately 100-million-year-old Kachin amber from Myanmar. Fossils can not only allow to identify structural defensive specializations, but also lifestyle and even behavioral aspects. We review here the different defensive strategies employed by various holometabolan larvae found in Kachin amber, also reporting new cases of a leaf-mining hymenopteran caterpillar and a hangingfly caterpillar with extensive spines. This overview demonstrates that already 100 million years ago many modern strategies had already evolved in multiple lineages, but also reveals some cases of now extinct strategies. The repetitive independent evolution of similar strategies in distantly related lineages indicates that several strategies evolved convergently as a result of similar selective pressures.

A new genus and species of the Nabidae (Hemiptera, Heteroptera, Cimicomorpha) from mid-Cretaceous amber of Northern Myanmar

A new genus and species of fossil Nabidae, Feroculipodus obtusidentatus gen. et sp. nov., is described from mid-Cretaceous amber, which represents the second fossil record of Nabidae from Myanmar and is classified under the subfamily Prostemmatinae. The new species is distinguished from other nabids based on the pronotum not clearly divided into an anterior and a posterior part, fore femur with an obtuse angular process on the ventral surface, basal cell on membrane absent. Research on the newly discovered fossil specimen as a source of character information, provides us with a new perspective to analysis the phylogenetic relationships of Nabidae through external morphological characters.

Birmaniaespina robustispina gen. et sp. nov., a new yuripopovinid bug from Cenomanian Kachin amber, Myanmar (Hemiptera, Pentatomomorpha)

The true bug family Yuripopovinidae was first reported in Lower Cretaceous amber of central Lebanon, and subsequently documented in the Lower Cretaceous of northeastern China and Cenomanian Kachin amber of Myanmar. Based on one well-preserved bug fossil trapped in Kachin amber, we herein describe and illustrate another new yuripopovinid taxon, Birmaniaespina robustispina gen. et sp. nov. The new genus and species can be easily distinguished from known yuripopovinids by bearing a series of deviant autapomorphic characters: one horn arranged on each lateral margin of head behind compound eye, pronotal posterior lobe surface reticular, and ovipositor extremely long and apparently extending beyond pygofer. The new bizarre yuripopovinid further evidences that this extinct pentatomomorph lineage once diversified multi-dimensionally and was flourishing in the late Mesozoic.