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A new beetle family, Mysteriomorphidae fam. nov. (Coleoptera: Elateriformia incertae sedis), from mid-Cretaceous amber of northern Myanmar



A new Cretaceous fossil beetle Mysteriomorphus pelevini gen. et sp. nov. is described from Burmese amber and a new family Mysteriomorphidae fam. nov. is proposed to accommodate this new taxon. The new monogeneric family is characterised by a combination of characters present in different lineages of Elateroidea and Byrrhoidea (Ptilodactylidae) and is therefore placed as incertae sedis in the series Elateriformia.
482 Accepted by D.-Y. Huang: 10 Oct. 2019; published: 31 Oct. 2019
Palaeoentomology 002 (5): 482–490
Copyright © 2019 Magnolia Press Article PALAEOENTOMOLOGY
ISSN 2624-2826 (print edition)
ISSN 2624-2834 (online edition) PE
A new Cretaceous fossil beetle Mysteriomorphus pelevini
gen. et sp. nov. is described from Burmese amber and a
new family Mysteriomorphidae fam. nov. is proposed
to accommodate this new taxon. The new monogeneric
family is characterised by a combination of characters
present in different lineages of Elateroidea and Byrrhoidea
(Ptilodactylidae) and is therefore placed as incertae sedis in
the series Elateriformia.
Keywords: Polyphaga, burmite, new taxa, palaeontology,
Mesozoic, fossil resin
Beetles appear in the Early Permian, Artinskian, 283.5–
290.1 Ma (Kukalová-Peck & Beutel, 2012), and the
modern taxonomical diversity of this most species-
rich metazoan order is the result of its approximately
290-million-year-long evolutionary history. Crown
Coleoptera originated in the earliest Permian or even
earlier, in the Carboniferous (Misof et al., 2014), the
divergence between the beetle series occurred mainly
during the Triassic, with most superfamilies appearing
during the Jurassic, and almost 64% of modern families
appearing in the Cretaceous (Zhang et al., 2018). As such,
the Cretaceous was an important period in shaping the
extreme diversity of beetles.
Cretaceous amber from northern Myanmar (burmite)
contains a rich assemblage of different groups of beetles
and is of the earliest Cenomanian in age (98.79 ± 0.62 Ma
years old) based upon the isotopic U-Pb dating of zircons
in the matrix surrounding the amber (Shi et al., 2012).
Recently, a Late Albian—Early Cenomanian age of this
fossil Lagerstätte has been mentioned based upon the
inclusion of a juvenile ammonite belonging to subgenus
that first appeared in the Upper Albian and ranged through
the Cenomanian (Yu et al., 2019).
Hundreds of papers dealing with different animal
inclusions from burmite have been published in the last
decade. The taxonomic checklist of Burmese amber
organisms (Ross, 2019) includes 206 described beetle
species, but new discoveries since that time have been
published and many other beetles await description. A
number of Mesozoic beetles from the West Burma Block
of a Gondwanan origin (Poinar, 2018) can be assigned to
Recent genera (e.g. Clarke & Chatzimanolis, 2009; Liu
et al., 2015; Cai et al., 2016, 2017; Háva & Damgaard,
2017; Deng et al., 2017; Ellenberger & Fanti 2019; Vitali
& Ellenberger 2019), many taxa represent new genera or
tribes in different extant families (e.g. Legalov & Poinar,
2014; Caterino et al., 2015; Kazantsev, 2015; Poinar et
al., 2016; Jałoszyński et al., 2017; Yamamoto et al., 2017;
Hsiao et al., 2018; Batelka et al., 2018; Fanti et al., 2018;
Legalov, 2018; Tomaszewska et al., 2018), several ones
are assigned to new subfamilies (e.g. Poinar et al., 2017;
Li et al., 2019), but several taxa cannot be unambiguously
placed within any modern family. Two beetle families,
Apotomouridae and Passalopalpidae, are known only
from Burmese amber fossils at present (Boucher et al.,
2016; Bao et al., 2018), but the number of family-level
lineages in Burmese amber that have gone extinct since the
Cretaceous seems to be higher and remains undescribed.
A new genus Mysteriomorphus gen. nov. and
species, M. pelevini sp. nov. are described and figured in
the present paper. These burmite beetles probably belong
to the stem lineage of the series Elateriformia Crowson
1960, showing a combination of characters found in the
superfamilies Elateroidea and Byrrhoidea, as well as
a unique combination of characters, and therefore it is
tentatively described as new family Mysteriomorphidae
fam. nov. and placed as incertae sedis in the series
Elateriformia without a more detailed attribution.
A new beetle family, Mysteriomorphidae fam. nov. (Coleoptera: Elateriformia
incertae sedis), from mid-Cretaceous amber of northern Myanmar
1Shirshov Institute of Oceanology, Russian Academy of Sciences, Nahimovskiy prospekt 36, 117997 Moscow, Russia.
2Kaliningrad Regional Amber Museum, Marshal Vasilevskii square 1, Kaliningrad, 236016, Russia.
3Bodelschwinghstraße 13, D-34119 Kassel, Germany.
*Corresponding author. Email:
488 Palaeoentomology 002 (5) © 2019 Magnolia Press
grooved to receive tibiae. The tibia with one acute and
slender apical spur; tibial spur almost indistinct between
quite long apical setae. Tarsi pentamerous, proportional
lengths of metatarsomeres: 1.2: 0.6: 0.5: 0.6: 0.7;
tarsomere 4 deeply bilobed; flashy pads on tarsomeres
absent. Claws falcate, acute, long and symmetrical.
Abdomen. With five ventrites of almost equal lengths.
Fifth ventrite simple, entire, without emargination
Mysteriomorphidae fam. nov. possesses a mosaic of
characters of two elateriform superfamilies, Elateroidea
and Byrrhoidea, and it is hard to decide to which of these it
is closer. The artificial classification of the new family (1)
including into diverse Ptilodactylidae as a non-specialized
primitive member or (2) including into one of the families
within Elateroidea as an aberrant form with support of
two to three characters is possible but is not considered
to be the best solution for forming of any well-balanced
system. Therefore, the new family is placed in the series
Elateriformia. It is hoped, that the discovery of additional
specimens or the application of ‘virtual palaeontology’
methods (3-D digital visualizations) additional to our
traditional approach may shed light on the adequate
phylogenetic position of Mysteriomorphidae fam. nov.
Further investigations using X-ray micro-computed
tomography (micro-CT) could help to study internal
features in better preserved specimens and may add data
important for understanding the systematic placement of
the taxon. Several “intermediate” or related fossil and
recent taxa can be found in future and shed some light on
the position of this particular fossil. At the moment, we
emphasize the phylogenetic position of Mysteriomorphus
gen. nov. as “an early-branching member of the series
Elateriformia” and the probable independence of this
Cretaceous extinct beetle lineage in the familial rank
of the newly proposed taxon. The verification of the
provided hypothesis and resolving of systematical
position of Mysteriomorphidae fam. nov. is possible by
conducting of comprehensive phylogenetic analysis using
an morphological matrix of extant Elateriformia.
Dr. Adam S. Ślipiński, Dr. John F. Lawrence, and
Dr. Hermes E. Escalona (all from CSIRO, Canberra,
Australia), Dr. Robin Kundrata and Dr. Ladislav Bocák
(both Palacký University, Olomouc, Czech Republic),
Fabrizio Fanti (Piazze, Italy), Dr. Manfred A. Jäch
(Vienna Natural History Museum, Wien, Austria), and
Dr. Sergey V. Kazantsev (Insect Centre, Moscow, Russia)
are cordially thanked for their helpful opinions about the
possible placement of the enigmatic beetles described
here. We thank Dr. Chenyang Cai (Nanjing Institute
of Geology and Palaeontology, Chinese Academy of
Sciences) and one anonymous reviewer for their valuable
suggestions that sufficiently improved the manuscript.
The study of V.I.A. was done with the support of the state
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... However, Cretopoena clearly differs from Agrypnini by its closed pronotosternal sutures and, therefore, its systematic position should be further investigated. Additionally, the suggested close relationship between Elateridae and recently discovered Mysteriomorphidae from the Cretaceous Burmese amber needs to be investigated using an analytical approach [241,242]. ...
... Last but not least, Elateridae students should pay special attention to the study of fossils included in amber deposits. Although the research of beetles (and other taxa) from various ambers is nowadays very popular [92,188,189,[250][251][252] and scientists were even able to describe within a short time span several new beetle families based on amber material [241,[253][254][255][256][257], the diversity of click-beetles in fossilized plant resins has been highly understudied. A study of the Elateridae diversity in amber is of great importance due to the three-dimensional preservation of specimens which allows us to compare the fossil fauna with extant specimens in much greater detail than in the case of compression fossils [188,229]. ...
Full-text available
The Elateridae (click-beetles) are the largest family in Elateroidea; however, their relationships, systematics and classification remain unclear. Our understanding of the origin, evolution, palaeodiversity and palaeobiogeography of Elateridae, as well as reconstruction of a reliable time-calibrated phylogeny for the group, are hampered by the lack of detailed knowledge of their fossil record. In this study, we summarize the current knowledge on all described fossil species in Elateridae, including their type material, geographic origin, age, bibliography and remarks on their systematic placement. Altogether, 261 fossil species classified in 99 genera and nine subfamilies are currently listed in this family. The Mesozoic click-beetle diversity includes 143 species, with most of them described from the Jurassic Karatau, and 118 described species are known from the Cenozoic deposits, mainly from the Eocene North American Florissant Formation and European Baltic amber. Available data on the described past diversity of Elateridae suggest that almost all fossil lineages in this group are in urgent need of revision and numerous Mesozoic species might belong to different families. Our study is intended to serve as a comprehensive basis for all subsequent research focused on the click-beetle fossil record.
... However, these characters are not consistent when we take into consideration also the type material of M. pelevini. The holotype is a small specimen but with pronotum as in NIGP173648 and NIGP173651, and the large paratype resembling the pronotum shape of the newly examined small specimens NIGP173649 and NIGP173650 (Figs. 1 and 2 21 ). Additionally, we do not know the sex of any of the specimens. ...
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The monospecific family Mysteriomorphidae was recently described based on two fossil specimens from the Late Cretaceous Kachin amber of northern Myanmar. The family was placed in Elateriformia incertae sedis without a clear list of characters that define it either in Elateroidea or in Byrrhoidea. We report here four additional adult specimens of the same lineage, one of which was described using a successful reconstruction from a CT-scan analysis to better observe some characters. The new specimens enabled us to considerably improve the diagnosis of Mysteriomorphidae. The family is definitively placed in Elateroidea, and we hypothesize its close relationship with Elateridae. Similarly, there are other fossil families of beetles that are exclusively described from Cretaceous ambers. These lineages may have been evolutionarily replaced by the ecological revolution launched by angiosperms that introduced new co-associations with taxa. These data indicate a macroevolutionary pattern of replacement that could be extended to other insect groups.
This is a supplement to Ross (2019) covering all taxa described or recorded in Burmese amber during 2019, plus a few earlier records that were missed previously. Up to the end of 2019, 1,478 species were recorded from Burmese (Kachin) amber of which 276 were named or recorded in 2019.
Full-text available
Sparedrus archaicus n. sp. (Coleoptera Oedemeridae) from Cretaceous amber from Myanmar is described and compared with congeners of the Recent.
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Amber is fossilized tree resin, and inclusions usually comprise terrestrial and, rarely, aquatic organisms. Marine fossils are extremely rare in Cretaceous and Cenozoic ambers. Here, we report a record of an ammonite with marine gastropods, intertidal isopods, and diverse terrestrial arthropods as syninclusions in mid-Cretaceous Burmese amber. We used X-ray–microcomputed tomography (CT) to obtain high-resolution 3D images of the ammonite, including its sutures, which are diagnostically important for ammonites. The ammonite is a juvenile Puzosia ( Bhimaites ) and provides supporting evidence for a Late Albian–Early Cenomanian age of the amber. There is a diverse assemblage (at least 40 individuals) of arthropods in this amber sample from both terrestrial and marine habitats, including Isopoda, Acari (mites), Araneae (spiders), Diplopoda (millipedes), and representatives of the insect orders Blattodea (cockroaches), Coleoptera (beetles), Diptera (true flies), and Hymenoptera (wasps). The incomplete preservation and lack of soft body of the ammonite and marine gastropods suggest that they were dead and underwent abrasion on the seashore before entombment. It is most likely that the resin fell to the beach from coastal trees, picking up terrestrial arthropods and beach shells and, exceptionally, surviving the high-energy beach environment to be preserved as amber. Our findings not only represent a record of an ammonite in amber but also provide insights into the taphonomy of amber and the paleoecology of Cretaceous amber forests.
In this paper, we describe a new genus and species of soldier beetles from Burmese amber, Elektrokleinia picta gen. et. sp. nov., characterized by triangular shape of the head behind the eyes, by the elytra not covering two urites and the last urite being concave at its apex. Additionally, this new specimen shows remarkable color preservation (black-blue) on the elytra, rarely present in amber or seen on fossil soldier beetles. This coloration with metallic nuances is here considered an aposematic character.
A list of all known taxa described or recorded from Burmese amber from the published literature up to the end of 2018 is given, along with a comprehensive bibliography. The history of the study of inclusions is summarised, and demonstrates that the number of species has risen exponentially over the past two decades. The first three species were named in 1916 and by the end of 1920 a total of 42 species had been named by T.D.A. Cockerell. Only three more species were named by 1999 though by the end of 2018 the total had risen to an incredible 1,192 species, of which over half were named in the past three years. Some 320 species were named in 2018, the highest number described from one type of amber in any one year in the entire history of amber studies.
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.
A new species and genus of polypore fungus beetle, Allostrophus cretaceus gen. et sp. nov., is described and illustrated, representing the third documented occurrence of Tetratomidae from Burmese amber (Cenomanian, ca. 99 Ma, Upper Cretaceous). This fossil species can be placed in the extant subfamily Eustrophinae based on the following combination of characters: small-sized, oblong-oval body, narrowed posteriorly; clubbed antennomeres; semicircular pronotum, with two weakly developed subbasal impressions; scutellum without light-colored pubescence and each elytron with traces of eight striae. Morphological characters preserved in the inclusion support the previously proposed high diversity of antennal morphology during the early evolution of eustrophines and suggest the potential fungivory of this extinct species. The new discovery sheds lights on the paleodiversity of mycophagous beetles during the Cretaceous period, strengthening the formerly hypothesized diversification of mushrooms in the late Mesozoic Era.
Four new genera along with four new species belonging to three subfamilies of the family Endomychidae (Coleoptera: Coccinelloidea) are described, diagnosed and imaged from Upper Cretaceous Burmese amber: Burmalestes albertalleni Tomaszewska and Ślipiński gen. et sp. nov., Cretolestes niger Tomaszewska, Ślipiński and Ren gen. et sp. nov. (Leiestinae), Cretaparamecus tarsalis Tomaszewska, Ślipiński, Bai and Zhang gen. et sp. nov. (Merophysiinae), and Palaeomycetes foveolatus Tomaszewska, Ślipiński and Ren gen. et sp. nov. (Xenomycetinae). They represent the oldest discovered definitive fossil members of the Endomychidae and the first records of the superfamily Coccinelloidea from the Burmese amber. Zemyna Tomaszewska nom. nov. is proposed as a replacement name for the recently described Laima Alekseev and Tomaszewska, 2018 (Endomychidae: Endomychinae) from the Eocene Baltic amber; Laima is the name already used in a fossil Brachiopoda (Gravitis, 1981).
A diversity of new wedge-shaped beetles (Coleoptera: Ripiphoridae) are described and figured from Burmese amber, representing three new genera and five new species in two subfamilies – Ripidiinae and Pelecotominae. Amberocula gen. nov., is the third genus of Ripidiini documented from the Upper Cretaceous (lowermost Cenomanian) amber of northern Myanmar. Three species are included in the genus: Amberocula muelleri sp. nov. (type species), A. costata sp. nov., and A. fallax sp. nov. Amberocula is represented by six single male inclusions and one quadruple male syninclusion (for A. muelleri). The genus is distinguishable by the combination of number and shape of antennomeres and tarsomeres, reduced mouthparts, and shape of the head, compound eyes, and thorax relative to all extant and fossil members of the tribe Ripidiini. In addition, three single male inclusions and one syninclusion of six males indistinguishable from Paleoripiphorus deploegi Perrichot, Nel, and Néraudeau (Ripidiini) are reported. Described syninclusions of both genera support the previous assumption of aggregative-like behavior of male Ripidiini may be a groundplan feature of the tribe and responsible for the presence of such syninclusions. Two monotypic genera, Plesiotoma alissae gen. et sp. nov. and Burmitoma nalae gen. et sp. nov., are representative of the subfamily Pelecotominae and are also described and figured. The inclusions represent the second and third definitive records for the subfamily in Cretaceous amber, and also the discovery of fossil pelecotomine females. They differ from the contemporaneous Flabellotoma Batelka, Engel, and Prokop in the presence of more complete tibial spur formulas and the absence of a ventral abdominal microsclerite. The presence of three species of Amberocula, additional material of P. deploegi, and two new genera of Pelecotominae demonstrates a surprising abundance of ripiphorids in Cretaceous amber, and we provide comments on the past diversity of this parasitoid family during the period, as well as observations on the nature of their preservation and paleoethology. The known diversity of Mesozoic Tenebrionoidea is cataloged and a key to the Cretaceous diversity of Ripiphoridae is presented.