Cretaceous Burmese Amber Research Articles

New paraneopterans (Protopsyllidioidea, Hemiptera) from the mid-Cretaceous amber of northern Myanmar

The generic diagnosis and the description of Postopsyllidium rebeccae Grimaldi, 2003 from Burmese amber are updated, based on new available data: new major characters are recognized, mostly concerning male terminalia and wing venation. Two new species, Postopsyllidium grimaldii sp. nov. and Postopsyllidium burmaticum sp. nov., are herein characterized, described and illustrated from the Cretaceous Burmese amber. This genus is also transferred to the newly created family Postopsyllidiidae fam. nov. Moreover, Permopsyllidiidae Becker-Migdisova, 1985 stat. nov. is elevated to family level from subfamily in Protopsyllidiidae Carpenter, 1931. The diagnoses and generic content for both families are revised.

Checklist of the Myriapoda in Cretaceous Burmese amber and a correction of the Myriapoda identified by Zhang (2017)

An inventory of the Myriapoda (Diplopoda, Chilopoda, Symphyla) from Cretaceous Burmese amber, Myanmar, is presented, including the oldest and/or first fossil record for numerous orders. For millipedes (Diplopoda) 527 records, including 460 new specimens determined by us, belonging to 13 of 16 recent orders are listed: Polyxenida, Glomeri­desmida, Glomerida, Siphonophorida, Polyzoniida, Platydesmida, Siphoniulida, Chordeumatida, Polydesmida, Stemmiulida, Callipodida, Spirostreptida and Spirobolida. For centipedes, 33 records for 4 of the 5 recent orders are listed: Scutigero­morpha, Lithobiomorpha, Scolopendromorpha and Geophilomorpha. For Symphyla, three records for both families, Scutigerellidae and Scolopendrellidae, are listed. The majority of Diplopoda records (30.5%) are Polydesmida. The record of the Polyzoniida includes first instar octopod juveniles. The checklist includes the first fossil representatives known of the Platydesmida, as well as the oldest known fossils of the Polyxenida, Glomeridesmida, Glomerida, Siphono­phorida, Polyzoniida, Siphoniulida, Spirostreptida, as well as both Symphyla families. Misidentifications by Zhang (2017) are corrected; while most Chilopoda in that list are correct, almost all Diplopoda are misidentified.

A new genus and species of Elcanidae (Insecta: Orthoptera) from Cretaceous Burmese amber

A new genus and species of Elcanidae (Insecta: Orthoptera) is described from mid-Cretaceous Burmese amber. Elcanonympha diana gen. et sp. nov. is known from a single, complete nymph and is distinguished from other elcanids by the pronotum cut by a single transverse sulcus, the dorsal margin of the metafemoral genicula with a row of prominent apical denticles, and the distal third of the metabasitarsus bearing a row of apically directed scale-like spines on the ventral surface.

Ornamental feathers in Cretaceous Burmese amber: resolving the enigma of rachis-dominated feather structure

Over the last 20 years, compression fossils of feathers surrounding dinosaurs have greatly expanded our understanding of the origin and evolution of feathers. One of the most peculiar feather morphotypes discovered to date are rachis dominated feathers (RDFs), which have also been referred to as proximally ribbon-like pennaceous feathers (PRPFs). These elongate feathers are only found in the tail plumage, typically occurring in pairs with both streamer (not proximally ribbon-like) and racket-plume morphologies recognized. Here we describe a large sample set of isolated and paired RDFs from Upper Cretaceous Burmese amber (~ 99 Ma). Amber preserves the finest details of these fragile structures in three dimensions, demonstrating that RDFs form a distinct feather morphotype with a ventrally open rachis, and with significant variability in pigmentation, microstructure, and symmetry.

The oldest Mycetobia Meigen, 1818 (Diptera, Anisopodoidea) from Upper Cretaceous amber of northern Myanmar

The oldest known representative of the genus Mycetobia, Mycetobia myanmara sp. nov., is described from Upper Cretaceous Burmese amber.

Sanaungulus ruicheni (Hsiao Huang, 2018) n. comb. with the differentialdiagnosis of genera Sanaungulus Fanti, Damgaard Ellenberger, 2018 and Ornatomalthinus Poinar Fanti, 2016.

Recently, Hsiao Huang (2018) presented a taxonomical revision of Ornatomalthinus Poinar Fanti, 2016 based on the discovery of a new species (O. ruicheni) from the Cretaceous Burmese amber of the Hukawng Valley (Myanmar). According to the authors, this species shows many differences in respect to O. elvirae Poinar Fanti, 2016. I propose that due to these morphological divergences the new species cannot belong to the genus Ornatomalthinus (type-species O. elvirae) as indicated by Hsiao Huang (2018). The appearance is in fact identical to Sanaungulus Fanti, Damgaard Ellenberger, 2018 (Poinar Fanti, 2016; Fanti et al., 2018). Additionally, Ornatomalthinus should remain in the subfamily Cantharinae. In this note the common characters of O. ruicheni and the criticalities of attribution to Ornatomalthinus are highlighted, a new combination is proposed and higher classification is discussed.

The First Fossil Limnichidae from the Upper Cretaceous Burmese Amber (Coleoptera: Byrrhoidea)

Fossil limnichids are very rare, and were known from the Cenozoic so far. Here we describe and illustrate the first definitive Mesozoic representative of the family Limnichidae, Erichia cretacea sp. nov., based on a well-preserved adult from the Upper Cretaceous Burmese amber. This taxon is firmly placed in the extant Cephalobyrrhinae based on multiple characteristics, such as body elongate and oval, base of pronotum and elytra incised and metacoxae transverse. The discovery of a Mesozoic fossil species classified in the recent genus suggests that Limnichidae and Cephalobyrrhinae are ancient groups, that experienced long evolutionary stasis.

Propiestus archaicus, the first Mesozoic amber inclusion of piestine rove beetles and its evolutionary and biogeographical significance (Coleoptera: Staphylinidae: Piestinae)

Fossil records of piestine rove beetles are very limited, with only two definite species from Mesozoic Chinese compressions, a single taxon from mid-Eocene Baltic amber and a doubtful Oligocene compression fossil from France. Here, a remarkable new genus and species, Propiestus archaicus gen. et sp. nov., is described based on a well-preserved individual in Upper Cretaceous Burmese amber from northern Myanmar (Cenomanian, c. 99 Ma). It represents the first piestine fossil found in Mesozoic amber. The fine morphological characters preserved as an amber inclusion enable a confident systematic placement within the subfamily based on both our detailed observations and phylogenetic analyses. The resulting trees revealed a strongly supported sister-group relationship with the extant genus Piestus, comprising all currently known piestine species from the Neotropical region and one from the Nearctic. Our new discovery is congruent with a hypothesis of the Gondwanan affinity of insects found from Burmese amber. Considering the geological data as well as several previous studies, the current distribution of Piestus could possibly be explained by either a relictual Gondwanan distribution or the widespread presence of the clade Propiestus + Piestus on Pangea, rather than subsequent dispersal events during the Cenozoic. Nonetheless, more evidence is needed to corroborate the true biogeographical origin and past distribution of this clade. In agreement with strong external similarities with living Piestinae, Propiestus probably exhibits a specialized body plan, including a flattened body, long, slender antennae and short legs, suggesting that it inhabited microhabitats under the bark of rotting wood as do its modern congeners.http://zoobank.org/urn:lsid:zoobank.org:pub:3411BDFD-54A1-4555-A870-813758BC61DA

New lacebugs (Hemiptera: Heteroptera: Tingidae) from Upper Cretaceous Burmese amber

From the Upper Cretaceous Burmese amber, only three genera and species of Tingidae (Spinitingis ellenbergeri Heiss and Guilbert, 2013; Burmacader multivenosus Heiss and Guilbert, 2013; and Tingiometra burmanica Heiss et al., 2015) have been reported to date. Two new genera and species Paraphatnomacader huarongcheni gen. et sp. nov. and Tingiphatnoma bispinosa gen. et sp. nov. are described and illustrated. Their phylogenetic relationships are discussed on the basis of a cladistics analysis, leading to an emergence of the Tingidae likely much older than ca. 125–135 Ma.

A giant mite in Cretaceous Burmese amber

Abstract. An unusually large acariform mite is described as Immensmaris chewbaccei gen. et sp. nov. from the Cretaceous (ca. 100 Ma) Burmese amber of Myanmar. With an idiosoma plus gnathosoma more than a centimetre long, it represents the largest unequivocal fossil mite ever recorded and approaches the maximum size of the largest living Acariformes today. Although some details of the dorsal idiosoma are equivocal, the new fossil appears to belong to Smarididae (Prostigmata: Parasitengona: Erythraeoidea) and also represents the largest erythraeoid mite ever discovered, indicating a clade of giant, possibly arboreal, mites in the Late Cretaceous of southeastern Asia.

Anisopodidae (Insecta: Diptera) from Upper Cretaceous amber of northern Myanmar

A new genus and three new species of Anisopodidae are described from the Cretaceous Burmese amber: Cretolbia hukawnga gen. et sp. nov., Cretolbia burmitica gen. et sp. nov., Cretolbia zhuodei gen. et sp. nov. Analyses of the morphological structures and taxonomical differences among representatives within the Anisopodidae have been carried out. A morphological comparison with their closest recent and fossil relatives is provided with the use of light and scanning electron microscopes.

New subfamily of ambrosia beetles (Coleoptera: Platypodidae) from mid-Cretaceous Burmese amber

ABSTRACTAn ambrosia beetle described as Palaeotylus femoralis n. gen et sp. belonging to a new subfamily (Palaeotylinae n. subfam.: Coleoptera: Platypodidae) is described from Cretaceous Burmese amber. It differs from other subfamilies by the loose antennal club, 6-articled funicle, coarsely faceted eyes, tibiae with teeth at apex, bilobed meso- and meta-tarsomeres 2 and 3 and tarsomere 1 shorter than tarsomeres 2–4 combined. This is the first described Platypodidae from Burmese amber and the oldest documented ambrosia beetle that demonstrates glandular sac mycangia containing yeast-like propagules and hyphal fragments.

The first wounded-tree beetle (Coleoptera: Nosodendridae) from Cretaceous Burmese amber

The first representative of the family Nosodendridae, Nosodendron cretaceum sp. nov., is described and figured from the Myanmar amber (ca. 98.79 ± 0.62 Ma). It differs from all known species of Nosodendron in having relatively elongate-oval body, the antennal scape and pedicel elongate with antennomere 3 subequal to or only slightly longer than pedicel. This is the first Mesozoic and the earliest record of the Nosodendridae. The Eocene Nosotetocus Scudder, 1892 (TS: Nosotetocus marcovi Scudder, 1892), Nosotetocus debilis Scudder, 1900, Nosotetocus vespertinus Scudder, 1900 and Nosodendron tritavum Scudder, 1900 not belong to Nosodendridae and are here provisionally transferred to Byrrhidae.

High niche diversity in Mesozoic pollinating lacewings

Niche diversity of pollinating insects plays a vital role in maintaining extant terrestrial ecosystems. A key dimension of pollination niches refers to the insect proboscis length that commonly matches the floral tube length. Here we describe new kalligrammatid lacewings (an iconic Mesozoic pollinating insect lineage) from late Cretaceous Burmese amber and Mesozoic sediments in China. Kalligrammatids display complex configurations of elongate mouthpart elements consisting of well-developed maxillae, labium and their palps. The mouthpart lengths vary among species, from 0.6 to 18.0 mm, suggesting corresponding variability in the floral tube lengths of Mesozoic plants. With the diversification of pollinating habits, the kalligrammatids presented highly divergent traits related to chemical communication and defence mechanisms. Together with other Mesozoic long-proboscid insects, these fossils not only reveal the high niche diversity of Mesozoic pollinating insects but also highlight the diversity of Mesozoic pollinator-dependent plants prior to the rise of angiosperms.

Marine microorganisms as amber inclusions: insights from coastal forests of New Caledonia

Abstract. Marine microorganisms trapped in amber are extremely rare in the fossil record, and the few existing inclusions recovered so far originate from very few pieces of Cretaceous amber from France. Marine macroscopic inclusions are also very rare and were recently described from Cretaceous Burmese amber and Early Miocene Mexican amber. Whereas a coastal setting for the amber source forests is generally proposed, different scenarios have been suggested to explain how these marine inclusions can become trapped in a resin of terrestrial origin. These scenarios include an introduction of marine organisms (i) through high tides, (ii) from storms and resulting in flooding of the littoral/estuarine forest floor, (iii) in resin dropped into the sea in mangrove-type settings, or (iv) by wind and sea spray. We investigated the possibility of a wind-driven introduction of marine microorganisms into tree resins using modern coastal conifer forests with the highly resinous Cook pine (Araucaria columnaris) in New Caledonia as a model for the Cretaceous amber forests from France. By exposing fresh resin surfaces on the seaward side of the trees and the collection of older in situ resins, we confirmed that marine microorganisms can become trapped on sea-exposed resin, along with remnants from terrestrial organisms, and salt crystals. We suggest that, for cases where only a few marine inclusions are discovered in an amber deposit, an origin from aeolian background deposition is feasible. However, a more energetic but possibly still aeolian event is likely needed to explain the high numbers of marine microorganisms embedded in pieces of Cretaceous amber from France.

Taxonomic revision on the genus Ornatomalthinus Poinar and Fanti (Coleoptera: Cantharidae), with description of a new species from the Cretaceous Burmese amber

Ornatomalthinus ruicheni sp. nov from the Upper Cretaceous (Cenomanian, ca. 99 Ma) Burmese amber is described and illustrated; this new species can be differentiated from its congener on the basis of the following characters: rounded anterior and posterior margins of the pronotum, surface of pronotal disc smooth, elytra broad in the basal half and lineally narrowing apically. The diagnostic characters of Ornatomalthinus are discussed and redefined. Furthermore, the new placement of Ornatomalthinus in the subfamily Silinae, tribe Silini is suggested. A potential flower-visiting preference is proposed for this species on the basis of the morphological similarities to extant cantharids and flowing-visiting beetles. Our discovery highlights the diversification of early soldier beetles, which may be closely related to the rise of angiosperms during the late Mesozoic.

New auger beetle (Coleoptera; Bostrichidae) from mid-Cretaceous Burmese amber

An auger beetle, Poinarinius burmaensis gen. et sp. nov. of the subfamily Dinoderinae (Bostrichidae) is described from Cretaceous Burmese amber. The new genus differs from other genera of this subfamily by the concave anterior margin of the pronotum, head visible from above and wider than the anterior margin of the pronotum, elongate and widely separated procoxae, antennae with 9 antennomeres, and body covered with long erect setae. It is distinguished from the genus Stephanopachys Waterhouse, 1888 by the transverse antennal club, protibiae with teeth, long tarsomeres 1–3, and elytra with a lobate convexity behind the middle. This is first record of the subfamily Dinoderinae (Bostrichidae) in Burmese amber.

Description of a Cretaceous amber fossil putatively of the tribe Coprophilini (Coleoptera, Staphylinidae, Oxytelinae).

An unusual and well-preserved fossil staphylinid is described and figured from a single specimen in Upper Cretaceous Burmese amber. Gollandiaplanatagen. et sp. n. is tentatively placed in the extant oxyteline tribe Coprophilini, although it lacks a few characteristic features of present-day members of the group, likely indicating it to be either a stem group of the tribe or prove to be distinct pending future discoveries. The discovery of this genus suggests that early oxytelines were more morphologically diverse during the Cretaceous and their evolutionary history was more complicated than previously documented. Tribal placement as regards fossil oxyteline taxa is discussed.

A new species of Tingidae from Cretaceous amber from Myanmar(Hemiptera, Heteroptera).

From the Upper Cretaceous Burmese amber, only three genera and species of Tingidae, (Spinitingis ellenbergeri and Burmacader multivenosus Heiss Guilbert, 2013; Tingiometra burmanica Heiss et al. 2015), are reported to date. A new species Burmacader lativentris sp.nov. is described and illustrated.

A new Cretaceous cockroach with heterogeneous tarsi preserved in Burmese amber (Dictyoptera, Blattodea, Corydiidae)

Here we describe a new corydiid cockroach, Nodosigalea burmanica gen. et sp. nov., from the middle Cretaceous Burmese amber. The well-preserved specimens exhibit a typical habitus of Corydiidae, and are characterized by nodulous pronotum, distinct wing venation and unique tarsi, the hind ones of which have different ventral structures from the fore- and midlegs. The combination of adhesive fore- and midtarsi and propulsive hindtarsi suggests a particular life style of the new genus. The phylogenetic position of the new genus within Corydiidae, however, is uncertain.