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Much of what we know about terrestrial life during the Carboniferous Period comes from Middle Pennsylvanian (~315–307 Mya) Coal Measures deposited in low-lying wetland environments1–5. We know relatively little about terrestrial ecosystems from the Early Pennsylvanian, which was a critical interval for the diversification of insects, arachnids, tetrapods, and seed plants6–10. Here we report a diverse Early Pennsylvanian trace and body fossil Lagerstätte (~320–318 Mya) from the Wamsutta Formation of eastern North America, distinct from coal-bearing deposits, preserved in clastic substrates within basin margin conglomerates. The exceptionally preserved trace fossils and body fossils document a range of vertebrates, invertebrates and plant taxa (n = 131), with 83 distinct foliage morphotypes. Plant-insect interactions include what may be the earliest evidence of insect oviposition. This site expands our knowledge of early terrestrial ecosystems and organismal interactions and provides ground truth for future phylogenetic reconstructions of key plant, arthropod, and vertebrate groups. Our knowledge of life in the Carboniferous Period is largely restricted to low-lying wetlands dated to 315–310 million years ago. Here, the authors present an older Lagerstätte on an alluvial fan 320–318 million years ago, preserving a diverse ecosystem of vertebrates, invertebrates, plants, and plant-insect interactions. [ABSTRACT FROM AUTHOR]

Dryopteridaceae are the basal family of Eupolypods I (Polypodiales) and include abundant extant species, but fossil occurrences are limited, particularly from a temporal perspective. Although DNA-based molecular studies indicate that the origin of Dryopteridaceae dates to the Early Cretaceous, no unambiguous fossil of the family has been reported from the Cretaceous period. Here, we report a new fern taxa based on well-preserved fertile specimen frond from mid-Cretaceous Kachin amber. Based on sporangia with interrupted, vertical annulae; monoletee spores; and the absence of indusia, the fertile fern fossil has been assigned to a new genus of Dryopteridaceae (Polypodiales). This represents the first fossil record of Dryopteridaceae from the Mesozoic and its mid-Cretaceous age is largely consistent with molecular-based estimates of divergence time. The fossil extends our understanding of polypod fern diversity in Mesozoic forests. [ABSTRACT FROM AUTHOR]

Termites (Blattodea: Isoptera) have evolved specialized defensive strategies for colony protection. Alarm communication enables workers to escape threats while soldiers are recruited to the source of disturbance. Here, we study the vibroacoustic and chemical alarm communication in the wood roach Cryptocercus and in 20 termite species including seven of the nine termite families, all life-types, and all feeding and nesting habits. Our multidisciplinary approach shows that vibratory alarm signals represent an ethological synapomorphy of termites and Cryptocercus. In contrast, chemical alarms have evolved independently in several cockroach groups and at least twice in termites. Vibroacoustic alarm signaling patterns are the most complex in Neoisoptera, in which they are often combined with chemical signals. The alarm characters correlate to phylogenetic position, food type and hardness, foraging area size, and nesting habits. Overall, species of Neoisoptera have developed the most sophisticated communication system amongst termites, potentially contributing to their ecological success. The vibroacoustic and chemical alarm communication in the wood roach Cryptocercus and in 20 termite species are studied to reveal that the Neoisoptera species have developed the most sophisticated communication system, which could contribute towards their ecological success. [ABSTRACT FROM AUTHOR]

Raphidioptera, the group of snakeflies, is a rather species-poor in-group of Holometabola. Yet, fossils of snakeflies indicate that the group was more diverse in the past. Here we compare the morphological diversity of snakefly larvae over time. Snakefly larvae are well represented in Cretaceous and Eocene ambers facilitating such a comparison. We used measurements of discrete dimensions as a basis for comparison. This reveals a larger diversity of snakefly larvae in the Cretaceous, especially in relation to head shapes and morphology of the antennae, which were much more variable. In particular, some Cretaceous larvae possessed greatly elongated head capsules and uniquely long and prominent antennae, unparalleled among modern forms. Already by the Eocene, snakefly larvae were less variable than those of the Cretaceous, although some still possessed longer antennae than modern-day larvae. The loss of morphological diversity supports the already well-established loss of taxonomic diversity in the group across time. Quite likely, this also indicates a loss of ecological diversity. These results are comparable to losses in different lineages of the closely related group Neuroptera. [ABSTRACT FROM AUTHOR]

Climate change (CC) is expected to negatively impact global biodiversity and ecosystems, resulting in profound ecological impacts and placing complex networks of biological interactions at risk. Despite this worrying scenario, the existing knowledge deficiencies may be overcome with species distribution models (SDMs), providing estimates of the effects of CC upon biodiversity. We evaluate the impact of CC on the distribution of the bumble bee species Bombus (Funebribombus) funebris Smith, 1854 (Apidae: Bombini) in South America. The Andean region will remain suitable for B. funebris under models of future CC. Nonetheless, the distribution range size will decrease, especially in protected areas. We believe this is due to the elevation zones preferentially occupied by the bees. The existence and prevalence of the species may be affected by anthropic actions and CC. The growing use of SDMs is critical to minimizing information deficits related to insect species and providing estimates of their distribution ranges. Implications for insect conservation: Implications for insect conservation: Our results show a retraction in the future distribution range of this bumble bee, dispersing to higher elevations. Therefore, it has the potential for the loss of plant–insect interactions by affecting its crucial role in Andean pollination. [ABSTRACT FROM AUTHOR]

Termites are a clade of eusocial wood-feeding roaches with > 3000 described species. Eusociality emerged ~ 150 million years ago in the ancestor of modern termites, which, since then, have acquired and sometimes lost a series of adaptive traits defining of their evolution. Termites primarily feed on wood, and digest cellulose in association with their obligatory nutritional mutualistic gut microbes. Recent advances in our understanding of termite phylogenetic relationships have served to provide a tentative timeline for the emergence of innovative traits and their consequences on the ecological success of termites. While all "lower" termites rely on cellulolytic protists to digest wood, "higher" termites (Termitidae), which comprise ~ 70% of termite species, do not rely on protists for digestion. The loss of protists in Termitidae was a critical evolutionary step that fostered the emergence of novel traits, resulting in a diversification of morphology, diets, and niches to an extent unattained by "lower" termites. However, the mechanisms that led to the initial loss of protists and the succession of events that took place in the termite gut remain speculative. In this review, we provide an overview of the key innovative traits acquired by termites during their evolution, which ultimately set the stage for the emergence of "higher" termites. We then discuss two hypotheses concerning the loss of protists in Termitidae, either through an externalization of the digestion or a dietary transition. Finally, we argue that many aspects of termite evolution remain speculative, as most termite biological diversity and evolutionary trajectories have yet to be explored. [ABSTRACT FROM AUTHOR]

Raphidioptera (snakeflies) are the least diverse order among extant Holometabola, representing relicts of their rich Mesozoic paleofauna. Baissopteridae are one of the two major lineages from the Mesozoic, but with a poorly known evolutionary history. Here, we report the first fossil record of Baissopteridae from the mid-Cretaceous of Myanmar, represented by a diverse assemblage including 10 new species in six genera: Allobaissoptera oligophlebia gen. et sp. nov., Baissoptera burmana sp. nov., B. maculata sp. nov., B. monopoda sp. nov., B. pankowskiorum sp. nov., B. wangi sp. nov., Burmobiassoptera jiaxiaoae gen. et sp. nov., Electrobaissoptera burmanica gen. et sp. nov., Rhynchobaissoptera hui gen. et sp. nov., and Stenobaissoptera xiai gen. et sp. nov. The new Cretaceous baissopterids provide significant morphological evidence in favor of the monophyly of this family. The morphological diversity in these Cretaceous baissopterids, particularly with some specialized and unique characters, highlights the early radiation of snakeflies formed in the complex tropical forest ecosystem of the mid-Cretaceous. [ABSTRACT FROM AUTHOR]

The first fossil leaf-mimicking katydids from the eastern Palaearctic are described and attributed to the genus Archepseudophylla under the names Archepseudophylla nanzhaoica sp. nov. and Archepseudophylla wenshanensis sp. nov., both from the Early to Middle Miocene strata in Wenshan, Yunnan, southwestern China, which is the core of the southwestern China karst region. This pseudophylline genus was previously known only from the Eocene–Oligocene of Europe, and is indicative of warm temperate to subtropical paleoclimatic conditions within the Yunnan region during this stage of the Miocene. [ABSTRACT FROM AUTHOR]

Species invasions are expected to increase continuously with undeniable impact upon native biodiversity, being an important process in relation to the decline of native pollinators. We used species distribution models and multivariate analyses to assess the climatic niche properties of the red dwarf honey bee, Apis florea Fabricius (Apidae: Apini), an open-nesting species native to southern Asia and parts of the Middle East, currently invading East Africa, Sundaic tropical Southeast Asia (Peninsular Malaysia and Singapore), and East Asia (Taiwan). The species' niche was relatively conserved, with the climatic conditions in all its invaded range overlapped by those from its native one. Its potential distribution in Africa and the Indomalayan region is broad, with anthropogenic areas likely providing new habitats and dispersal corridors in areas that were formerly too arid or too heavily forested to allow its dispersal. Future studies to evaluate the potential impacts of A. florea in invaded ranges are encouraged. [ABSTRACT FROM AUTHOR]

Nearly all of Earth's ecosystems are suffering rapid and intense environmental changes, pushing species extinction rates to levels higher than those previously observed in past mass-extinction events. In this context, the ongoing effects of climate change are expected to cause severe impacts on biodiversity in the near- to medium-term future. Yet, the lack of knowledge concerning the geographic distributions of species is an important drawback to the efficacy of practical actions towards species conservation. Species distribution models (SDMs) may help to overcome these knowledge shortfalls and evaluate the potential effects of climate change upon species distributions. Here, we made use of these tools to measure the potential effects of future climate change upon the distribution of Merope tuber Newman (Mecoptera: Meropeidae). Our SDM results show that the range of the species is expected to increase under almost all modeling methods employed. Such a change in range is mainly related to a poleward shift. Practically nothing is known about M. tuber's ecology, but nonetheless, the future climate changes are expected to affect the species' ecological features. This reinforces the need to increase resources for field surveys of this (and other) insect lineages. Such measures will provide more robust information on the biological and ecological attributes of species, allowing stakeholders to design more efficient tools to protect this species before human-related activities impose irreversible negative impacts. [ABSTRACT FROM AUTHOR]

Myrmeleontiformia are an ancient group of lacewing insects characterized by predatory larvae with unusual morphologies and behaviours. Mostly soil dwellers with a soft cuticle, their larvae fossilize only as amber inclusions, and thus their fossil record is remarkably sparse. Here, we document a disparate assemblage of myrmeleontiform larvae from the mid-Cretaceous amber (99 Ma) of Myanmar, evidence of a considerable diversification. Our cladistic analysis integrating extant and extinct taxa resolves the fossils as both stem- and crown-groups. Similarities between extinct and extant species permit inferences of larval ethology of the fossil species through statistical correlation analyses with high support, implying that morphological disparity matched behavioural diversity. An improved understanding of the evolutionary history of antlions and relatives supports the conclusion that hunting strategies, such as camouflage and fossoriality, were acquired early within the lineage. [ABSTRACT FROM AUTHOR]

The Eumetabola (Endopterygota (also known as Holometabola) plus Paraneoptera) have the highest number of species of any clade, and greatly contribute to animal species biodiversity. The palaeoecological circumstances that favoured their emergence and success remain an intriguing question. Recent molecular phylogenetic analyses have suggested a wide range of dates for the initial appearance of the Holometabola, from the Middle Devonian epoch (391 million years (Myr) ago) to the Late Pennsylvanian epoch (311 Myr ago), and Hemiptera (310 Myr ago). Palaeoenvironments greatly changed over these periods, with global cooling and increasing complexity of green forests. The Pennsylvanian-period crown-eumetabolan fossil record remains notably incomplete, particularly as several fossils have been erroneously considered to be stem Holometabola (Supplementary Information); the earliest definitive beetles are from the start of the Permian period. The emergence of the hymenopterids, sister group to other Holometabola, is dated between 350 and 309 Myr ago, incongruent with their current earliest record (Middle Triassic epoch). Here we describe five fossils- a Gzhelian-age stem coleopterid, a holometabolous larva of uncertain ordinal affinity, a stem hymenopterid, and early Hemiptera and Psocodea, all from the Moscovian age-and reveal a notable penecontemporaneous breadth of early eumetabolan insects. These discoveries are more congruent with current hypotheses of clade divergence. Eumetabola experienced episodes of diversification during the Bashkirian-Moscovian and the Kasimovian-Gzhelian ages. This cladogenetic activity is perhaps related to notable episodes of drying resulting from glaciations, leading to the eventual demise in Euramerica of coal-swamp ecosystems, evidenced by floral turnover during this interval. These ancient species were of very small size, living in the shadow of Palaeozoic-era 'giant' insects. Although these discoveries reveal unexpected Pennsylvanian eumetabolan diversity, the lineage radiated more successfully only after the mass extinctions at the end of the Permian period, giving rise to the familiar crown groups of their respective clades. [ABSTRACT FROM AUTHOR]

The species of the Strashilidae (strashilids) have been the most perplexing of fossil insects from the Jurassic period of Russia and China. They have been widely considered to be ectoparasites of pterosaurs or feathered dinosaurs, based on the putative presence of piercing and sucking mouthparts and hind tibio-basitarsal pincers purportedly used to fix onto the host's hairs or feathers. Both the supposed host and parasite occur in the Daohugou beds from the Middle Jurassic epoch of China (approximately 165 million years ago). Here we analyse the morphology of strashilids from the Daohugou beds, and reach markedly different conclusions; namely that strashilids are highly specialized flies (Diptera) bearing large membranous wings, with substantial sexual dimorphism of the hind legs and abdominal extensions. The idea that they belong to an extinct order is unsupported, and the lineage can be placed within the true flies. In terms of major morphological and inferred behavioural features, strashilids resemble the recent (extant) and relict members of the aquatic fly family Nymphomyiidae. Their ontogeny are distinguished by the persistence in adult males of larval abdominal respiratory gills, representing a unique case of paedomorphism among endopterygote insects. Adult strashilids were probably aquatic or amphibious, shedding their wings after emergence and mating in the water. [ABSTRACT FROM AUTHOR]

After terrestrialization, the diversification of arthropods and vertebrates is thought to have occurred in two distinct phases, the first between the Silurian and the Frasnian stages (Late Devonian period) (425-385 million years (Myr) ago), and the second characterized by the emergence of numerous new major taxa, during the Late Carboniferous period (after 345 Myr ago). These two diversification periods bracket the depauperate vertebrate Romer's gap (360-345 Myr ago) and arthropod gap (385-325 Myr ago), which could be due to preservational artefact. Although a recent molecular dating has given an age of 390 Myr for the Holometabola, the record of hexapods during the Early-Middle Devonian (411.5-391 Myr ago, Pragian to Givetian stages) is exceptionally sparse and based on fragmentary remains, which hinders the timing of this diversification. Indeed, although Devonian Archaeognatha are problematic, the Pragian of Scotland has given some Collembola and the incomplete insect Rhyniognatha, with its diagnostic dicondylic, metapterygotan mandibles. The oldest, definitively winged insects are from the Serpukhovian stage (latest Early Carboniferous period). Here we report the first complete Late Devonian insect, which was probably a terrestrial species. Its 'orthopteroid' mandibles are of an omnivorous type, clearly not modified for a solely carnivorous diet. This discovery narrows the 45-Myr gap in the fossil record of Hexapoda, and demonstrates further a first Devonian phase of diversification for the Hexapoda, as in vertebrates, and suggests that the Pterygota diversified before and during Romer's gap. [ABSTRACT FROM AUTHOR]

Fleas are one of the major lineages of ectoparasitic insects and are now highly specialized for feeding on the blood of birds or mammals. This has isolated them among holometabolan insect orders, although they derive from the Antliophora (scorpionflies and true flies). Like most ectoparasitic lineages, their fossil record is meagre and confined to Cenozoic-era representatives of modern families, so that we lack evidence of the origins of fleas in the Mesozoic era. The origins of the first recognized Cretaceous stem-group flea, Tarwinia, remains highly controversial. Here we report fossils of the oldest definitive fleas-giant forms from the Middle Jurassic and Early Cretaceous periods of China. They exhibit many defining features of fleas but retain primitive traits such as non-jumping hindlegs. More importantly, all have stout and elongate sucking siphons for piercing the hides of their hosts, implying that these fleas may be rooted among the pollinating 'long siphonate' scorpionflies of the Mesozoic. Their special morphology suggests that their earliest hosts were hairy or feathered 'reptilians', and that they radiated to mammalian and bird hosts later in the Cenozoic. [ABSTRACT FROM AUTHOR]

Insects are the most diverse lineage of all life in numbers of species, and ecologically they dominate terrestrial ecosystems. However, how and when this immense radiation of animals originated is unclear. Only a few fossils provide insight into the earliest stages of insect evolution, and among them are specimens in chert from Rhynie, Scotland's Old Red Sandstone (Pragian; about 396-407 million years ago), which is only slightly younger than formations harbouring the earliest terrestrial faunas. The most well-known animal from Rhynie is the springtail Rhyniella praecursor (Entognatha; Collembola), long considered to be the oldest hexapod. For true insects (Ectognatha), the oldest records are two apparent wingless insects from later in the Devonian period of North America. Here we show, however, that a fragmentary fossil from Rhynie, Rhyniognatha hirsti, is not only the earliest true insect but may be relatively derived within basal Ectognatha. In fact, Rhyniognatha has derived characters shared with winged insects, suggesting that the origin of wings may have been earlier than previously believed. Regardless, Rhyniognatha indicates that insects originated in the Silurian period and were members of some of the earliest terrestrial faunas. [ABSTRACT FROM AUTHOR]

The early fossilization steps of natural resins and associated terminology are a subject of constant debate. Copal and resin are archives of palaeontological and historical information, and their study is critical to the discovery of new and/or recently extinct species and to trace changes in forests during the Holocene. For such studies, a clear, suitable definition for copal is vital and is herein established. We propose an age range for copal (2.58 Ma—1760 AD), including Pleistocene and Holocene copals, and the novel term "Defaunation resin", defined as resin produced after the commencement of the Industrial Revolution. Defaunation resin is differentiated from Holocene copal as it was produced during a period of intense human transformative activities. Additionally, the "Latest Amber Bioinclusions Gap" (LABG) since the late Miocene to the end of the Pleistocene is hereby newly defined, and is characterized by its virtual absence of bioinclusions and the consequent lack of palaeontological information, which in part explains the historical differentiation between amber and copal. Crucial time intervals in the study of resin production, and of the biodiversity that could be contained, are now clarified, providing a framework for and focusing future research on bioinclusions preserved in copal and resin. [ABSTRACT FROM AUTHOR]

Hadrosaurian dinosaurs were abundant in the Late Cretaceous of North America, but their habitats remain poorly understood. Cretaceous amber is also relatively abundant, yet it is seldom found in direct stratigraphic association with dinosaur remains. Here we describe an unusually large amber specimen attached to a Prosaurolophus jaw, which reveals details of the contemporaneous paleoforest and entomofauna. Fourier-transform Infrared spectroscopy and stable isotope composition (H and C) suggest the amber formed from resins exuded by cupressaceous conifers occupying a coastal plain. An aphid within the amber belongs to Cretamyzidae, a Cretaceous family suggested to bark-feed on conifers. Distinct tooth row impressions on the amber match the hadrosaur's alveolar bone ridges, providing some insight into the taphonomic processes that brought these remains together. [ABSTRACT FROM AUTHOR]

Angiosperms and their insect pollinators form a foundational symbiosis, evidence for which from the Cretaceous is mostly indirect, based on fossils of insect taxa that today are anthophilous, and of fossil insects and flowers that have apparent anthophilous and entomophilous specializations, respectively. We present exceptional direct evidence preserved in mid-Cretaceous Burmese amber, 100 mya, for feeding on pollen in the eudicot genus Tricolporoidites by a basal new aculeate wasp, Prosphex anthophilos, gen. et sp. nov., in the lineage that contains the ants, bees, and other stinging wasps. Plume of hundreds of pollen grains wafts from its mouth and an apparent pollen mass was detected by micro-CT in the buccal cavity: clear evidence that the wasp was foraging on the pollen. Eudicots today comprise nearly three-quarters of all angiosperm species. Prosphex feeding on Tricolporoidites supports the hypothesis that relatively small, generalized insect anthophiles were important pollinators of early angiosperms. Grimaldi et al. report on a primitive stinging wasp preserved in mid-Cretaceous amber from Myanmar, encapsulated just after it fed on the pollen of a eudicot. Micro-CT shows a pollen mass in the wasp's mouth cavity, supporting the idea that insect anthophiles were important pollinators of early angiosperms. [ABSTRACT FROM AUTHOR]

The largest insects to have ever lived were the giant meganeurids of the Late Palaeozoic, ancient stem relatives of our modern dragonflies. With wingspans up to 71 cm, these iconic insects have been the subject of varied documentaries on Palaeozoic life, depicting them as patrolling for prey through coal swamp forests amid giant lycopsids, and cordaites. Such reconstructions are speculative as few definitive details of giant dragonfly biology are known. Most specimens of giant dragonflies are known from wings or isolated elements, but Meganeurites gracilipes preserves critical body structures, most notably those of the head. Here we show that it is unlikely it thrived in densely forested environments where its elongate wings would have become easily damaged. Instead, the species lived in more open habitats and possessed greatly enlarged compound eyes. These were dorsally hypertrophied, a specialization for long-distance vision above the animal in flight, a trait convergent with modern hawker dragonflies. Sturdy mandibles with acute teeth, strong spines on tibiae and tarsi, and a pronounced thoracic skewness are identical to those specializations used by dragonflies in capturing prey while in flight. The Palaeozoic Odonatoptera thus exhibited considerable morphological specializations associated with behaviours attributable to ‘hawkers’ or ‘perchers’ among extant Odonata. [ABSTRACT FROM AUTHOR]

Insecta s. str. (=Ectognatha), comprise the largest and most diversified group of living organisms, accounting for roughly half of the biodiversity on Earth. Understanding insect relationships and the specific time intervals for their episodes of radiation and extinction are critical to any comprehensive perspective on evolutionary events. Although some deeper nodes have been resolved congruently, the complete evolution of insects has remained obscure due to the lack of direct fossil evidence. Besides, various evolutionary phases of insects and the corresponding driving forces of diversification remain to be recognized. In this study, a comprehensive sample of all insect orders was used to reconstruct their phylogenetic relationships and estimate deep divergences. The phylogenetic relationships of insect orders were congruently recovered by Bayesian inference and maximum likelihood analyses. A complete timescale of divergences based on an uncorrelated log-normal relaxed clock model was established among all lineages of winged insects. The inferred timescale for various nodes are congruent with major historical events including the increase of atmospheric oxygen in the Late Silurian and earliest Devonian, the radiation of vascular plants in the Devonian, and with the available fossil record of the stem groups to various insect lineages in the Devonian and Carboniferous. [ABSTRACT FROM AUTHOR]

replying to T. Hörnschemeyer et al. Nature 494, http://dx.doi.org/10.1038/nature11887 (2013)10.1038/nature11887Since the nineteenth century, Devonian insects have repeatedly proven to be something else, the sole exception being Rhyniognatha. Recently the Devonian insect Strudiella devonica has been denied by Hörnschemeyer et al., who could not 'confirm the presence of a mandible or of mandibular teeth'. [ABSTRACT FROM AUTHOR]