Generalist Pollen-Feeding Beetles during the Mid-Cretaceous

The contribution of the Middle Triassic fossil assemblage of Monte San Giorgio to insect evolution

The Triassic represents a critical period for understanding the turnover of insect fauna from the Paleozoic to the Mesozoic following the end-Permian mass extinctions (EPME); however, fossil deposits from the Early-Middle Triassic are scarce. The exceptionally preserved 239 million-year-old fossil insect fauna recorded at Monte San Giorgio (Switzerland), including 248 fossils representing 15 major insect clades is presented here. Besides the exceptional features, including their small size and excellent preservation, the fossils have importance in the evolutionary history of the group. The taxonomic and ecological diversity recovered, including both freshwater (dragonflies and caddisflies) and terrestrial taxa (true bugs and wasps), demonstrates that complex environments sustained a paleocommunity dominated by monurans (thought not to have survived the EPME), midges, and beetles. Interestingly, a blattodean-like fossil bearing an external ootheca was also found, important for understanding Paleozoic roachoids to extant cockroaches' transition and the evolution of maternal brood care. Moreover, the youngest and first complete specimen of †Permithonidae and the oldest sawfly fossils were discovered. Finally, round-shaped bodies, compatible with seminal capsules or lycophyte spores, were found on the abdomens of several midge-like individuals. If these are spores, non-seed-bearing plants could have been the first entomophilous plants rather than gymnosperms, as recently supposed. Altogether, these fossils contribute substantially to understanding insect evolution and Paleozoic-Mesozoic faunal turnover.

The angiosperm radiation played a dual role in the diversification of insects and insect pollinators

Interactions with angiosperms have been hypothesised to play a crucial role in driving diversification among insects, with a particular emphasis on pollinator insects. However, support for coevolutionary diversification in insect-plant interactions is weak. Macroevolutionary studies of insect and plant diversities support the hypothesis that angiosperms diversified after a peak in insect diversity in the Early Cretaceous. Here, we used the family-level fossil record of insects as a whole, and insect pollinator families in particular, to estimate diversification rates and the role of angiosperms on insect macroevolutionary history using a Bayesian process-based approach. We found that angiosperms played a dual role that changed through time, mitigating insect extinction in the Cretaceous and promoting insect origination in the Cenozoic, which is also recovered for insect pollinator families only. Although insects pollinated gymnosperms before the angiosperm radiation, a radiation of new pollinator lineages began as angiosperm lineages increased, particularly significant after 50 Ma. We also found that global temperature, increases in insect diversity, and spore plants were strongly correlated with origination and extinction rates, suggesting that multiple drivers influenced insect diversification and arguing for the investigation of different explanatory variables in further studies.

Mechanistic understanding of perianth traits hindering pollination in Aristolochia contorta Bunge

Insects are vital pollinators for angiosperms, playing a crucial role in their reproductive success and fruit production. Aristolochia contorta is a perennial herbaceous vine that occurs in fragmented populations across East Asia. One notable feature of this plant is its trap flower, which employs a unique mechanism to attract, trap, retain, and release insects, ensuring effective pollination. The presence of this trap flower significantly influences the pollination system of A. contorta. Field surveys and pollination experiments were conducted to understand the processes and effectiveness of its pollination mechanism. It was allogamous and was pollinated by the species from Ceratopogonidae. During the insect attraction stage, 11.57% of the flowers contained insects, primarily Ceratopogonidae spp. Most Ceratopogonidae spp. concentrated in few flowers, indicating that although overall attraction might be modest, specific flowers acted as significant focal points for gathering. Trichomes effectively trapped Ceratopogonidae spp. inside flower tubes. In the retention stage, 26.16% of Ceratopogonidae spp. were loaded with pollen grains, but only 7.91% of those exited the flowers in the release stage. The sticky texture of the perianth's internal cavity posed challenges during this release, leading to adhesion and clogging of the narrow perianth tube. Consequently, a significant portion of Ceratopogonidae spp. became trapped on the perianth wall and perished. This highlights that despite the significant energy and resources invested in flower development, the perianth contributes to the low pollination effectiveness. This study revealed additive factors with negative effects on pollination, including the densely clustered distribution of its pollinators within only a few flowers, insufficient pollen loading onto pollinators, hindered release of entrapped pollinators due to the perianth adhesive surface, and a high rate of defective pollen grains in A. contorta. These factors account for the observed phenomenon of low fruit set (7.7%) and contribute to the diminished rate of sexual reproduction in A. contorta populations. This might lead the species to heavily rely on asexual reproduction, which could potentially lead to gene erosion within populations. The implications of these findings extend to the ecological and conservation aspects, emphasizing the need to understand and conserve the unique pollination system of A. contorta.

A New Subgenus of the Genus Phenolia (Coleoptera, Nitidulidae) from Myanmar Cretaceous Amber with Taxonomic, Phylogenetic and Bionomic Notes on the 'Nitidulid' Group of Families

A new subgenus, Palaeoronia subgen. nov., is described from the Cretaceous amber of North Myanmar (Kachin State) and assigned to the genus Phenolia. The type species of the new subgenus, Phenolia (Palaeoronia) haoranae subgen. et sp. nov., is characterized by a rather 'archaic' aspect. A discussion of the diagnostic and structure of the Soronia-complex of genera (together with the Phenolia-complex of genera) (Nitidulinae, Nitidulini) is proposed. Reasons for the 'conservatism' of this group during the Mesozoic and Cenozoic are discussed. The position of the Apophisandridae stat. nov. (type genus Apophisandra) and the transfers of the following genera into this family: Cretaretes, Electrumeretes, Furcalabratum, Pelretes, Polliniretes, Protokateretes, Protonitidula, and Scaporetes, from the Kateretidae, Nitidulidae or Cerambycidae are grounded. The relations of the family Parandrexidae (with inclusion of the genus Cretoparacucujus, transferred from Boganiidae with a proposal of the subfamily Cretoparacucujinae subfam.nov.), Martynoposis and Parandrexis are considered. The genus Antirhelus gen. nov. (type species Heterhelus buzina) is assigned to the new subfamily, Antirhelinae subfam. nov. in the family Kateretidae. The fossil records of the 'nitidulid' group of families (Apophisandridae stat. nov., Kateretidae, Nitidulidae, Parandrexidae, Smicripidae and possibly Boganiidae) are reviewed. The relationship of the family Boganiidae, some aspects of pollination and pollinophagy, and also changes in beetle diet in the past are discussed. The lectotype of Parandrixis parvula is designated.

Insect pollination in deep time

Inferring insect pollination from compression fossils and amber inclusions is difficult because of a lack of consensus on defining an insect pollinator and the challenge of recognizing this ecological relationship in deep time. We propose a conceptual definition for such insects and an operational classification into pollinator or presumed pollinator. Using this approach, we identified 15 insect families that include fossil pollinators and show that pollination relationships have existed since at least the Upper Jurassic (~163 Ma). Insects prior to this can only be classified as presumed pollinators. This gives a more nuanced insight into the origin and evolution of an ecological relationship that is vital to the establishment, composition and conservation of modern terrestrial ecosystems.

Morphological Study of the Alimentary Canal and Malpighian Tubules in the Adult of the Pollen Beetle Meligethes (Odonthogethes) chinensis (Coleoptera: Nitidulidae: Meligethinae)

Meligethes (Odonthogethes) chinensis is a highly specialized species of Nitidulidae in China that takes pollen as its main food source, and its main host plant is Rubus idaeus L. (Rosaceae). In this study, the structural morphology of the alimentary canal and Malpighian tubules of adult M. (O.) chinensis was observed under light, fluorescence, and scanning electron microscopy. The alimentary canal of adult M. (O.) chinensis is divided into foregut, midgut, and hindgut. The foregut is the shortest and consists of the pharynx, esophagus, proventriculus, and cardiac valve. The midgut is a straight, distended, cylindrical, thin-walled tube. Numerous blunt-fingered gastric ceca are distributed irregularly throughout the midgut. The hindgut is subdivided into the ileum, colon, and rectum. The ileum is coiled. The colon gradually enlarges posteriorly. The rectum is thickly muscled and followed by a membranous structure. The openings of proximal Malpighian tubules are evenly inserted into the junction of the midgut and hindgut, and distal Malpighian tubules are evenly attached to the colon to form a cryptonephridial system. In this study, we also compare the structure and infer the function of the alimentary canal and Malpighian tubules among beetles, as well as discuss the evolutionary and taxonomical implications.

The earliest pollen-loaded insects from the Lower Permian of Russia

Recent fossil discoveries suggest that the coevolution of insect pollinators and gymnosperms started long before the appearance of flowering plants. One of the keys to understanding the origins of pollination relationships is fossil insects with gymnosperm pollen attached to the body surface. Such fossils are exceedingly rare to find, especially from the Palaeozoic, a time when ambers with insect inclusions were absent. Here, we report compression fossils of Early Permian tillyardembiid insects (Polyneoptera) preserved with pollen on their heads, thoraces, legs and abdomens. This is the earliest finding of pollen-bearing insects, predating the previous oldest record from the Middle Jurassic by ca 120 Ma. Judging by the pollen composition, tillyardembiids visited a narrow range of host plants, including Rufloriaceae (Cordaitales). While it is impossible to say for certain whether tillyardembiids as pollen consumers contributed to pollination, a trophic specialization of this kind could be considered an evolutionary precursor of pollination mutualism.

Arthropod and Pathogen Damage on Fossil and Modern Plants: Exploring the Origins and Evolution of Herbivory on Land

The use of the functional feeding group-damage type system for analyzing arthropod and pathogen interactions with plants has transformed our understanding of herbivory in fossil plant assemblages by providing data, analyses, and interpretation of the local, regional, and global patterns of a 420-Myr history. The early fossil record can be used to answer major questions about the oldest evidence for herbivory, the early emergence of herbivore associations on land plants, and later expansion on seed plants. The subsequent effects of the Permian-Triassic ecological crisis on herbivore diversity, the resulting formation of biologically diverse herbivore communities on gymnosperms, and major shifts in herbivory ensuing from initial angiosperm diversification are additional issues that need to be addressed. Studies ofherbivory resulting from more recent transient spikes and longer-term climate trends provide important data that are applied to current global change and include herbivore community responses to latitude, altitude, and habitat. Ongoing paleoecological themes remaining to be addressed include the antiquity of modern interactions, differential herbivory between ferns and angiosperms, and origins of modern tropical forests. The expansion of databases that include a multitude of specimens; improvements in sampling strategies; development of new analytical methods; and, importantly, the ability to address conceptually stimulating ecological and evolutionary questions have provided new impetus in this rapidly advancing field.

A New Genus of Short-Winged Flower Beetles with an Enlarged Antennal Scape in Mid-Cretaceous Amber from Northern Myanmar (Coleoptera: Kateretidae)

The fossil records of Kateretidae from the Mesozoic are significant for understanding the origin and early evolution of the family. The recent discoveries of Cretaceous kateretids have provided valuable information about the palaeodiversity and morphological disparity of the taxa. Here, we establish a new genus and species of kateretid beetles, Scaporetes rectus gen. et sp. nov., based on a specimen preserved in mid-Cretaceous Kachin amber from northern Myanmar. The new species is characterized by its strongly enlarged scape and extremely small labrum. Our discovery highlights the morphological disparity of Kateretidae in the late Mesozoic.

A New Genus of Sap Beetles (Coleoptera: Nitidulidae) from Mid-Cretaceous Amber of Northern Myanmar

Nitidulidae is the most diverse family of the recently recognized superfamily Nitiduliodea, but Mesozoic nitidulids that are critical for understanding their early diversification are sparse. Here, we report a new genus and species of Nitidulidae, Protonitidula neli gen. et sp. nov., that was recovered from mid-Cretaceous amber in northern Myanmar. The new genus is distinguished from all members of the extant nitidulid subfamilies most prominently by the loose antennal club and the absence of subantennal grooves. Protonitidula neli can be excluded from the closely related Kateretidae and classified into Nitidulidae by the broad and apically expanded prosternal process, although it has many pleisiomorphic characters.

Early diversifications of angiosperms and their insect pollinators: were they unlinked?

The present-day ubiquity of angiosperm-insect pollination has led to the hypothesis that these two groups coevolved early in their evolutionary history. However, recent fossil discoveries and fossil-calibrated molecular dating analyses challenge the notion that early diversifications of angiosperms and insects were inextricably linked. In this article, we examine (i) the discrepancies between dates of emergence for angiosperms and major clades of insects; (ii) the long history of gymnosperm-insect pollination modes, which likely shaped early angiosperm-insect pollination mutualisms; and (iii) how the K-Pg (Cretaceous-Paleogene) mass extinction event was vital in propelling modern angiosperm-insect mutualisms. We posit that the early diversifications of angiosperms and their insect pollinators were largely decoupled until the end of the Cretaceous.

Ecological radiations of insects in the Mesozoic

The Mesozoic is a key era for the rise of the modern insect fauna. Among the most important evolutionary events in Mesozoic insects are the radiation of holometabolous insects, the origin of eusocial and parasitoid insects, diversification of pollinating insects, and development of advanced mimicry and camouflage. These events are closely associated with the diversification of insect ecological behaviors and colonization of new ecospaces. At the same time, insects had evolved more complex and closer ecological associations with various plants and animals. Mesozoic insects played a key and underappreciated ecological role in reconstructing and maintaining terrestrial ecosystems. A greater understanding of the history of insects may help to mitigate future changes in insect diversity and abundance.

Dinosaur bonebed amber from an original swamp forest soil

Dinosaur bonebeds with amber content, yet scarce, offer a superior wealth and quality of data on ancient terrestrial ecosystems. However, the preserved palaeodiversity and/or taphonomic characteristics of these exceptional localities had hitherto limited their palaeobiological potential. Here, we describe the amber from the Lower Cretaceous dinosaur bonebed of Ariño (Teruel, Spain) using a multidisciplinary approach. Amber is found in both a root layer with amber strictly in situ and a litter layer mainly composed of aerial pieces unusually rich in bioinclusions, encompassing 11 insect orders, arachnids, and a few plant and vertebrate remains, including a feather. Additional palaeontological data—charophytes, palynomorphs, ostracods— are provided. Ariño arguably represents the most prolific and palaeobiologically diverse locality in which fossiliferous amber and a dinosaur bonebed have been found in association, and the only one known where the vast majority of the palaeontological assemblage suffered no or low-grade pre-burial transport. This has unlocked unprecedentedly complete and reliable palaeoecological data out of two complementary windows of preservation—the bonebed and the amber—from the same site.

The earliest beetle with mouthparts specialized for feeding on nectar is a parasitoid of mid-Cretaceous Hymenoptera

Background

During the Mesozoic, there were many insects in several holometabolous orders (Neuroptera, Mecoptera and Diptera) with elongated mouthparts adapted for feeding on nectar. The evolutionary history of the megadiverse order Coleptera, which has a great diversity of mouthparts and feeding strategies, is well documented since early Permian with a significant peak in diversity in the Triassic. Currently, however, there is no evidence that in the Mesozoic these beetles fed on nectar despite the recorded specializations for pollination of flowering plants in several families since the mid-Cretaceous.

Results

Here we describe a new wedge-shaped beetle Melanosiagon serraticornis gen. et sp. nov. from mid-Cretaceous Burmese amber attributed to Macrosiagonini (Ripiphoridae: Ripiphorinae), which has elongated galea comparable to that in the extant parasitoid genus Macrosiagon, and a well known example of adaptation for nectar feeding in Coleoptera. Furthermore, Salignacicola gen. nov. is established for Macrosiagon ebboi Perrichot, Nel et Néraudeau, 2004, based on the holotype found in mid-Cretaceous amber from France. Systematic positions of both newly established genera are discussed. A list of potential wasp and bee hosts of Ripiphorinae from the Mesozoic is provided.

Conclusions

This study presents evidence of the earliest occurrence of specialized nectar feeding mouthparts in Coleoptera. Melanosiagon serraticornis is closely related to extant Macrosiagonini. In all genera belonging to subfamily Ripiphorinae the primary larvae are adapted for parasitism on aculeate Hymenoptera (bees and wasps) and adults are associated with blossoms of flowering plants, in terms of their specialized morphology. Adults of Macrosiagon visit blossoms of flowering plants to obtain nectar and lay eggs from which the hatching larvae attack visiting wasps and bees. An association with flowers of some tropical trees is already corroborated in some extant species. Interestingly the larvae of Ripiphorinae are also found in Burmese amber. Thus, both life stages of the mid-Cretaceous Ripiphorinae indicate a close association of this lineage with flowering trees.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12862-021-01930-6.

Ecology and Evolution of Gall-Inducing Arthropods: The Pattern From the Terrestrial Fossil Record

Insect and mite galls on land plants have a spotty but periodically rich and abundant fossil record of damage types (DTs), ichnotaxa, and informally described gall morphotypes. The earliest gall is on a liverwort of the Middle Devonian Period at 385 million years ago (Ma). A 70-million-year-long absence of documented gall activity ensues. Gall activity resumes during the Pennsylvanian Period (315 Ma) on vegetative and reproductive axial organs of horsetails, ferns, and probably conifers, followed by extensive diversification of small, early hemipteroid galler lineages on seed-plant foliage during the Permian Period. The end-Permian (P-Tr) evolutionary and ecological crisis extinguished most gall lineages; survivors diversified whose herbivore component communities surpassed pre-P-Tr levels within 10 million years in the mid-to late Triassic (242 Ma). During the late Triassic and Jurassic Period, new groups of galling insects colonized Ginkgoales, Bennettitales, Pinales, Gnetales, and other gymnosperms, but data are sparse. Diversifying mid-Cretaceous (125–90 Ma) angiosperms hosted a major expansion of 24 gall DTs organized as herbivore component communities, each in overlapping Venn-diagram fashion on early lineages of Austrobaileyales, Laurales, Chloranthales, and Eurosidae for the Dakota Fm (103 Ma). Gall diversification continued into the Ora Fm (92 Ma) of Israel with another 25 gall morphotypes, but as ichnospecies on a different spectrum of plant hosts alongside the earliest occurrence of parasitoid attack. The End-Cretaceous (K-Pg) extinction event (66 Ma) almost extinguished host–specialist DTs; surviving gall lineages expanded to a pre-K-Pg level 10 million years later at the Paleocene-Eocene Thermal Maximum (PETM) (56 Ma), at which time a dramatic increase of land surface temperatures and multiplying of atmospheric pCO2 levels induced a significant level of increased herbivory, although gall diversity increased only after the PETM excursion and during the Early Eocene Climatic Optimum (EECO). After the EECO, modern (or structurally convergent) gall morphotypes originate in the mid-Paleogene (49–40 Ma), evidenced by the Republic, Messel, and Eckfeld floras on hosts different from their modern analogs. During subsequent global aridification, the early Neogene (20 Ma) Most flora of the Czech Republic records several modern associations with gallers and plant hosts congeneric with their modern analogs. Except for 21 gall DTs in New Zealand flora, the gall record decreases in richness, although an early Pleistocene (3 Ma) study in France documents the same plant surviving as an endemic northern Iran but with decreasing associational, including gall, host specificity.

Florivory of Early Cretaceous flowers by functionally diverse insects: implications for early angiosperm pollination

Florivory (flower consumption) occurs worldwide in modern angiosperms, associated with pollen and nectar consumption. However, florivory remains unrecorded from fossil flowers since their Early Cretaceous appearance. We test hypotheses that earliest angiosperms were pollinated by a diverse insect fauna by evaluating 7858 plants from eight localities of the latest Albian Dakota Formation from midcontinental North America, in which 645 specimens (8.2%) were flowers or inflorescences. Well-preserved specimens were categorized into 32 morphotypes, nine of which displayed 207 instances of damage from 11 insect damage types (DTs) by four functional-feeding groups of hole feeding, margin feeding, surface feeding and piercing-and-sucking. We assessed the same DTs inflicted by known florivores on modern flowers that also are their pollinators, and associated insect mouthpart types causing such damage. The diverse, Dakota florivore-pollinator community showed a local pattern at Braun's Ranch of flower morphotypes 4 and 5 having piercing-and-sucking as dominant and margin feeding as minor interactions, whereas Dakotanthus cordiformis at Rose Creek I and II had an opposite pattern. We found no evidence for nectar robbing. These data support the rapid emergence of early angiosperms of florivore and associated pollinator guilds expressed at both the local and regional community levels.

Opsin Evolution in Flower-Visiting Beetles

Flowers have evolved signals that exploit the sensory systems of insect visitors. In the case of visual cues, color signals are thought to have been shaped in large part by the spectral sensitivity of key pollinators, such as hymenopterans. Beetles were some of the first plant pollinators, pre-dating the angiosperm radiation but with the exception of a few well-studied species, the evolution of flower-visiting beetle visual systems is poorly understood. Thus, the ability of beetles to detect and distinguish flower color signals and perhaps their potential role in shaping flower coloration is not well understood. Traditional models of pollinator visual systems often assume a putative tri- or tetrachromatic flower-visitor, as is found in bees, flies and butterflies. Beetles are unique among modern pollinators as ancestrally they did not possess the machinery for trichromatic vision, lacking the blue-sensitive photoreceptor class. Research on the evolution of visual genes responsible for wavelength sensitivity (opsins) has revealed that beetles with putative tri- and tetrachromatic visual systems have evolved independently, along multiple lineages. We explore the evolution of beetle visual genes using newly generated and publicly available RNA-seq data from 25 species with flower associations, including previously unexplored key flower-visitor groups and 20 non-flower visiting relatives. Our findings serve as a resource to inform and guide future studies on beetle-flower interactions, where insight from both signal and receiver is needed to better understand these poorly explored systems.

A Bizarre Planthopper Nymph (Hemiptera: Fulgoroidea) from Mid-Cretaceous Kachin Amber

Simple Summary

The fossil record of adult planthoppers is relatively rich, but the nymphs are rare and not well studied. Here, we describe a bizarre armoured planthopper nymph: Spinonympha shcherbakovi gen. et sp. nov. from mid-Cretaceous Kachin amber. The new genus and species is characterized by its large size, armoured body, extremely long rostrum, and leg structure. The fossil nymph cannot be attributed to any known planthopper family, but can be excluded from many families due to its large size and leg structure. The armoured body was probably developed for defence, and the extremely long rostrum indicates that, in the past, planthopper feeding on trees with thick and rough bark was more widespread than today. The new find reveals a new armoured morphotype previously unknown in planthopper nymphs.

Abstract

The fossil record of adult planthoppers is comparatively rich, but nymphs are rare and not well studied. Here, we describe a bizarre armoured planthopper nymph, Spinonympha shcherbakovi gen. et sp. nov., in mid-Cretaceous Kachin amber. The new genus is characterized by its large size, body armed with spines and tubercles, extremely long rostrum reaching well beyond the apex of the abdomen; profemur and mesofemur subcylindrical, covered with setae; protibia and mesotibia subquadrangular, densely covered with setae; protarsus and mesotarsus with two segments, tarsomere II longer and wider than I; metatrochanter swollen, metafemur subcylindrical, covered with short setae; metatibia subquadrangular, densely covered with short setae, without lateral spine and pectens without setae; metatarsus with three segments, and metatarsomere III extremely small. The fossil nymph cannot be attributed to any known planthopper family, but can be excluded from many families due to its large size and leg structure. The armoured body was probably developed for defence, and the extremely long rostrum indicates that, in the past, feeding on trees with thick and rough bark was more widespread than today. These features indicate that the new specimen represents a new armoured morphotype of planthopper nymph from the fossil record.

Angiosperm pollinivory in a Cretaceous beetle

Despite the crucial importance of flower-visiting insects in modern ecosystems, there is little fossil evidence on the origins of angiosperm pollination. Most reports of pollination in the Mesozoic fossil record have been based on the co-occurrence of the purported pollinators with pollen grains and assumed morphological adaptations for vectoring pollen. Here, we describe an exceptionally preserved short-winged flower beetle (Cucujoidea: Kateretidae) from mid-Cretaceous amber, Pelretes vivificus gen. et sp. nov., associated with pollen aggregations and coprolites consisting mainly of pollen, providing direct evidence of pollen-feeding in a Cretaceous beetle and confirming that diverse beetle lineages visited early angiosperms in the Cretaceous. The exquisite preservation of our fossil permits the identification of the pollen grains as Tricolpopollenites (Asteridae or Rosidae), representing a record of flower beetle pollination of a group of derived angiosperms in the Mesozoic and suggesting that potentially diverse beetle lineages visited early angiosperms by the mid-Cretaceous.

Unlocking the mystery of the mid-Cretaceous Mysteriomorphidae (Coleoptera: Elateroidea) and modalities in transiting from gymnosperms to angiosperms

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.