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Background: Recent advances in multivariate pattern recognition have fostered the search for reliable neuroimaging-based biomarkers in psychiatric conditions, including schizophrenia. These approaches consider the complex pattern of alterations in brain function and structure, overcoming the limitations of traditional univariate methods. To assess the reliability of neuroimaging-based biomarkers and the contribution of study characteristics in distinguishing individuals with schizophrenia spectrum disorder (SSD) from healthy controls (HCs), we conducted a systematic review of the studies that used multivariate pattern recognition for this objective., Methods: We systematically searched PubMed, Scopus, and Web of Science for studies on SSD classification using multivariate pattern analysis on magnetic resonance imaging data. We employed a bivariate random-effects meta-analytic model to explore the classification of sensitivity (SE) and specificity (SP) across studies while also evaluating the moderator effects of clinical and non-clinical variables., Results: A total of 119 studies (with 12,723 patients with SSD and 13,196 HCs) were identified. The meta-analysis estimated a SE of 79.1% (95% confidence interval [CI], 77.1%-81.0%) and a SP of 80.0% (95% CI, 77.8%-82.0%). In particular, the Positive and Negative Syndrome Scale and the Global Assessment of Functioning scores, age, age of onset, duration of untreated psychosis, deep learning, algorithm type, features selection, and validation methods had significant effects on classification performance., Conclusions: Multivariate pattern analysis reliably identifies neuroimaging-based biomarkers of SSD, achieving ∼80% SE and SP. Despite clinical heterogeneity, discernible brain modifications effectively differentiate SSD from HCs. Classification performance depends on patient-related and methodological factors crucial for the development, validation, and application of prospective models in clinical settings., (© 2024 The Author(s). Psychiatry and Clinical Neurosciences published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Psychiatry and Neurology.)

Background and Hypothesis: Altered functional connectivity (FC) has been frequently reported in psychosis. Studying FC and its time-varying patterns in early-stage psychosis allows the investigation of the neural mechanisms of this disorder without the confounding effects of drug treatment or illness-related factors., Study Design: We employed resting-state functional magnetic resonance imaging (rs-fMRI) to explore FC in individuals with early psychosis (EP), who also underwent clinical and neuropsychological assessments. 96 EP and 56 demographically matched healthy controls (HC) from the Human Connectome Project for Early Psychosis database were included. Multivariate analyses using spatial group independent component analysis were used to compute static FC and dynamic functional network connectivity (dFNC). Partial correlations between FC measures and clinical and cognitive variables were performed to test brain-behavior associations., Study Results: Compared to HC, EP showed higher static FC in the striatum and temporal, frontal, and parietal cortex, as well as lower FC in the frontal, parietal, and occipital gyrus. We found a negative correlation in EP between cognitive function and FC in the right striatum FC (pFWE = 0.009). All dFNC parameters, including dynamism and fluidity measures, were altered in EP, and positive symptoms were negatively correlated with the meta-state changes and the total distance (pFWE = 0.040 and pFWE = 0.049)., Conclusions: Our findings support the view that psychosis is characterized from the early stages by complex alterations in intrinsic static and dynamic FC, that may ultimately result in positive symptoms and cognitive deficits., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Schizophrenia (SCZ) and bipolar disorders (BD) show significant neurobiological and clinical overlap. In this study, we wanted to identify indexes of intrinsic brain activity that could differentiate these disorders. We compared the diagnostic value of the fractional amplitude of low-frequency fluctuations (fALFF) and regional homogeneity (ReHo) estimated from resting-state functional magnetic resonance imaging in a support vector machine classification of 59 healthy controls (HC), 40 individuals with SCZ, and 43 individuals with BD type I. The best performance, measured by balanced accuracy (BAC) for binary classification relative to HC was achieved by a stacking model (87.4% and 90.6% for SCZ and BD, respectively), with ReHo performing better than fALFF, both in SCZ (86.2% vs. 79.4%) and BD (89.9% vs. 76.9%). BD were better differentiated from HC by fronto-temporal ReHo and striato-temporo-thalamic fALFF. SCZ were better classified from HC using fronto-temporal-cerebellar ReHo and insulo-tempo-parietal-cerebellar fALFF. In conclusion, we provided evidence of widespread aberrancies of spontaneous activity and local connectivity in SCZ and BD, demonstrating that ReHo features exhibited superior discriminatory power compared to fALFF and achieved higher classification accuracies. Our results support the complementarity of these measures in the classification of SCZ and BD and suggest the potential for multivariate integration to improve diagnostic precision., (© 2024. The Author(s).)

Advanced social behavior, or eusociality, has been evolutionarily profound, allowing colonies of ants, termites, social wasps, and bees to dominate competitively over solitary species throughout the Cenozoic. Advanced sociality requires not just nestmate cooperation and specialization but refined coordination and communication. Here, we provide independent evidence that 100-million-year-old Cretaceous ants in amber were social, based on chemosensory adaptations. Previous studies inferred fossil ant sociality from individual ants preserved adjacent to others. We analyzed several fossil ants for their antennal sensilla, using original rotation imaging of amber microinclusions, and found an array of antennal sensilla, specifically for alarm pheromone detection and nestmate recognition, sharing distinctive features with extant ants. Although Cretaceous ants were stem groups, the fossilized sensilla confirm hypotheses of their complex sociality.

Objectives: The purpose of this study was to describe the frequency of arrhythmias detected in unsedated feline patients from general practice settings., Animals: A total 10,638 feline electrocardiograms (ECGs) were retrospectively collected of which 9440 met the inclusion criteria., Methods: Recordings were evaluated by a board-certified cardiologist. If an arrhythmia was present in the ECG tracing, the cardiologist categorized the arrhythmia using pre-established keywords., Results: At least one arrhythmia was observed in 249 cases (2.64%, 95% confidence interval (CI): 2.34-2.98, 249/9440), with the most common arrhythmia encountered being ventricular premature complexes (1.63%, 95% CI: 1.39%-1.91%, 154/9440). Ragdoll cats had the highest odds of arrhythmia (odds ratio (OR): 3.17, 95% CI: 1.43-6.17, P=0.036). Both geriatric (Age: 13+ years, OR: 1.70, 95% CI: 1.24-2.34, P=0.013) and senior (Age: 10-13 years, OR: 1.68, 95% CI: 1.19-2.37, P=0.003) cats had higher odds of having an arrhythmia than adult cats. The odds of male cats having an arrhythmia were slightly higher than female (OR: 1.36, 95% CI: 1.06-1.76, P=0.018)., Conclusions and Relevance: Of the 9440 ECGs included in this study, at least one arrhythmia was detected in 249 distinct cases. Arrhythmias were more common in older cats, male cats and the Ragdoll cat breed. While it is important to note that the presence of an arrhythmia alone does not always indicate the presence of heart disease, further research on the association between breed cardiac health is needed., Competing Interests: Conflict of Interest Statement All the authors except AHE, ELC, and DAG are employed by IDEXX., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Introduction: Bipolar disorder (BD) is a severe mental disorder characterized by high heritability rates. Widespread brain cortical alterations have been reported in BD patients, mostly involving the frontal, temporal and parietal regions. Importantly, also unaffected relatives of BD patients (BD-RELs) present abnormalities in cortical measures, which are not influenced by disease-related factors, such as medication use and illness duration. Here, we collected all available evidence on cortical measures in BD-RELs to further our knowledge on the potential cortical alterations associated with the vulnerability and the resilience to BD., Methods: A search on PubMed, Web of Science and Scopus was performed to identify neuroimaging studies exploring cortical alterations in BD-RELs, including cortical thickness (CT), surface area (SA), gyrification (GI) and cortical complexity. Eleven studies were included. Of these, five assessed CT, five examined CT and SA and one explored CT, SA and GI., Results: Overall, a heterogeneous pattern of cortical alterations emerged. The areas more consistently linked with genetic liability for BD were the prefrontal and sensorimotor regions. Mixed evidence was reported in the temporal and cingulate areas., Limitations: The small sample size and the heterogeneity in terms of methodologies and the characteristics of the participants limit the generalizability of our results., Conclusions: Our findings suggest that the genetic liability for BD is related to reduced CT in the prefrontal cortex, which might be a marker of risk for BD, and increased CT within the sensorimotor cortex, which could represent a marker of resilience., Competing Interests: Declaration of competing interest None., (Copyright © 2023. Published by Elsevier B.V.)

Background and Hypothesis: Several studies have shown that spontaneous brain activity, including the total and fractional amplitude of low-frequency fluctuations (LFF) and regional homogeneity (ReHo), is altered in psychosis. Nonetheless, neuroimaging results show a high heterogeneity. For this reason, we gathered the extant literature on spontaneous brain activity in first-episode psychosis (FEP), where the effects of long-term treatment and chronic disease are minimal., Study Design: A systematic research was conducted on PubMed, Scopus, and Web of Science to identify studies exploring spontaneous brain activity and local connectivity in FEP estimated using functional magnetic resonance imaging. 20 LFF and 15 ReHo studies were included. Coordinate-Based Activation Likelihood Estimation Meta-Analyses stratified by brain measures, age (adolescent vs adult), and drug-naïve status were performed to identify spatially-convergent alterations in spontaneous brain activity in FEP., Study Results: We found a significant increase in LFF in FEP compared to healthy controls (HC) in the right striatum and in ReHo in the left striatum. When pooling together all studies on LFF and ReHo, spontaneous brain activity was increased in the bilateral striatum and superior and middle frontal gyri and decreased in the right precentral gyrus and the right inferior frontal gyrus compared to HC. These results were also replicated in the adult and drug-naïve samples., Conclusions: Abnormalities in the frontostriatal circuit are present in early psychosis independently of treatment status. Our findings support the view that altered frontostriatal can represent a core neural alteration of the disorder and could be a target of treatment., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Extant terrestrial vertebrates, including birds, have a panoply of symbiotic relationships with many insects and arachnids, such as parasitism or mutualism. Yet, identifying arthropod-vertebrate symbioses in the fossil record has been based largely on indirect evidence; findings of direct association between arthropod guests and dinosaur host remains are exceedingly scarce. Here, we present direct and indirect evidence demonstrating that beetle larvae fed on feathers from an undetermined theropod host (avian or nonavian) 105 million y ago. An exceptional amber assemblage is reported of larval molts (exuviae) intimately associated with plumulaceous feather and other remains, as well as three additional amber pieces preserving isolated conspecific exuviae. Samples were found in the roughly coeval Spanish amber deposits of El Soplao, San Just, and Peñacerrada I. Integration of the morphological, systematic, and taphonomic data shows that the beetle larval exuviae, belonging to three developmental stages, are most consistent with skin/hide beetles (family Dermestidae), an ecologically important group with extant keratophagous species that commonly inhabit bird and mammal nests. These findings show that a symbiotic relationship involving keratophagy comparable to that of beetles and birds in current ecosystems existed between their Early Cretaceous relatives.

The study of terrestrial arthopod fossils preserved with microscopic fidelity in amber and as permineralized replicas has been revolutionized by CT scanning. Fine preservation facilitates phylogenetic interpretation of fossils, but molecular divergence-time models still commonly use insufficient fossil calibrations, skewing estimates away from the direct (i.e. fossil, morphological) evidence. Interactions among terrestrial arthropods (predation, parasitoidism; phoresy, social symbionts) are briefly reviewed from the fossil record. Predation is the oldest and most widespread, originating with arachnids since probably the Silurian. The first phoretic arthropods were probably mites (Acari). Parasitoidism extends to the early Jurassic ~200 mya, with four main episodes proposed by [1•]. 100-myo Burmese amber, the most diverse Cretaceous paleobiota, is unique for our understanding of insect eusociality and interrelationships among terrestrial arthropods. Eusocial insect colonies are ecological sinks for thousands of symbiont species; ages of the major eusocial groups and some of their nest symbionts are discussed. Fossilized arthropod interrelationships in Miocene Dominican amber are presented as visual exemplars., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The first fossil Archaeidae in Cambay amber from India, of Eocene age, is documented. The inclusion is a spider exuvium and is placed as Myrmecarchaea based on the presence of elongated legs, a slightly elongated pedicel with lateral spurs, and a diastema between coxae III and IV that is similar to M.antecessor from Oise amber. The previous occurrences of the genus are from Baltic and Oise amber, both of Eocene age. Because most spiders, including Archaeidae, only molt as juveniles, the exuvium does not have adult features nor have distinct species-specific features, and a new taxon is not erected. This new record further extends the distribution of the family and genus to India 50-52 million years ago. Myrmecarchaea in Indian Cambay amber provides additional evidence that India in the Early Eocene had affinities with the Palearctic mainland rather than showing Gondwanan insularity.

Premise: Early Eocene ambers of the Cambay lignite in Gujarat, India, are well known for their diverse insect fauna and dispersed pollen, but the included flowers have received limited attention. The fossil record of Apocynaceae is relatively poor, and the distinctive floral characters of this family have not been recognized in the fossil record before., Methods: Remains of tiny flowers in amber were studied by micro-CT scanning, reflected light, and epifluorescence microscopy., Results: Flowers of Maryendressantha succinifera gen. et. sp. n. have actinomorphic, pentamerous, tubular corollas 2.2-2.3 mm wide, and 1.7-2.1 mm deep with sinistrorse aestivation and androecia consisting of a whorl of five stamens attached by short filaments to the lower half of the corolla tube. Anthers are ovate, rounded basally and apically tapered with their connectives convergent with one another in a conical configuration. The pollen is globose, psilate, tricolporate, and very small (10-11 µm). The combined characters indicate a position within the grade known as subfamily Rauvolfioideae., Conclusions: These fossils, as the oldest remains of Rauvolfioids, complement the fossil records of Apocynoid and Asclepioid fossil seeds from other regions, demonstrating that the Apocynaceae were well established by the early Eocene, mostly consistent with prior divergence estimates for the phylogeny of this family. Potential pollinators, also preserved in the Cambay amber, include mosquitos, gnats, small moths, and stingless bees., (© 2021 Botanical Society of America.)

Two African drosophilids have distinctive protarsal spines in both sexes: Drosophila spinipes Lamb, 1914 from the Seychelles and D. suma Burla, 1954 from the Ivory Coast. Both were later classified in the genus Hirtodrosophila Duda of the Zygothrica genus group, and suma synonymized under spinipes by Tsacas (2006). We resurrect suma from synonymy, define the spinipes species group, and add seven new species in the group from Africa and Madagascar: Drosophila cameroonensis n. sp., D. freidbergi n. sp., D. hypandrilata n. sp., D. jambiya n. sp., D. malagasy n. sp., D. nigrospinipes n. sp., and D. phalloserra n. sp. Another four species are reported but not described. Detailed morphology informs that these anthophilous flies do not belong to the Zygothrica genus group, and they are returned to the genus Drosophila (unplaced to subgenus), albeit primitive members with some very distinctive specialized features. All distribution records, published and new, are presented along with a key to all nine named species.

Insects have long been thought to largely not require hemoglobins, with some notable exceptions like the red hemolymph of chironomid larvae. The tubular, branching network of tracheae in hexapods is traditionally considered sufficient for their respiration. Where hemoglobins do occur sporadically in plants and animals, they are believed to be either convergent, or because they are ancient in origin and their expression is lost in many clades. Our comprehensive analysis of 845 Hexapod transcriptomes, totaling over 38 Gbases, revealed the expression of hemoglobins in all 32 orders of hexapods, including the 29 recognized orders of insects. Discovery and identification of 1333 putative hemoglobins were achieved with target-gene BLAST searches of the NCBI TSA database, verifying functional residues, secondary- and tertiary-structure predictions, and localization predictions based on machine learning. While the majority of these hemoglobins are intracellular, extracellular ones were recovered in 38 species. Gene trees were constructed via multiple-sequence alignments and phylogenetic analyses. These indicate duplication events within insects and a monophyletic grouping of hemoglobins outside other globin clades, for which we propose the term insectahemoglobins. These hemoglobins are phylogenetically adjacent and appear structurally convergent with the clade of chordate myoglobins, cytoglobins, and hemoglobins. Their derivation and co-option from early neuroglobins may explain the widespread nature of hemoglobins in various kingdoms and phyla. These results will guide future work involving genome comparisons to transcriptome results, experimental investigations of gene expression, cell and tissue localization, and gas binding properties, all of which are needed to further illuminate the complex respiratory adaptations in insects., Competing Interests: The authors declare that no competing interests exist.

Myxomycetes constitute a group within the Amoebozoa well known for their motile plasmodia and morphologically complex fruiting bodies. One obstacle hindering studies of myxomycete evolution is that their fossils are exceedingly rare, so evolutionary analyses of this supposedly ancient lineage of amoebozoans are restricted to extant taxa. Molecular data have significantly advanced myxomycete systematics, but the evolutionary history of individual lineages and their ecological adaptations remain unknown. Here, we report exquisitely preserved myxomycete sporocarps in amber from Myanmar, ca. 100 million years old, one of the few fossil myxomycetes, and the only definitive Mesozoic one. Six densely-arranged stalked sporocarps were engulfed in tree resin while young, with almost the entire spore mass still inside the sporotheca. All morphological features are indistinguishable from those of the modern, cosmopolitan genus Stemonitis, demonstrating that sporocarp morphology has been static since at least the mid-Cretaceous. The ability of myxomycetes to develop into dormant stages, which can last years, may account for the phenotypic stasis between living Stemonitis species and this fossil one, similar to the situation found in other organisms that have cryptobiosis. We also interpret Stemonitis morphological stasis as evidence of strong environmental selection favouring the maintenance of adaptations that promote wind dispersal.

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., Competing Interests: Competing interestsThe authors declare no competing interests., (© The Author(s) 2019.)

David Grimaldi introduces amber and the fossils contained therein., (Copyright © 2019. Published by Elsevier Ltd.)

For slightly more than a century only the type specimen has been known for Pyrgometopa penicillata, a monotypic genus of Drosophilidae whose sole species has an ocellar triangle distended into a bizarre tubercle bearing a tuft of large, spine-like bristles in both sexes. Here we report additional specimens of both sexes of the species, recently rediscovered from Brazil, Peru and French Guyana, allowing us to state that Pyrgometopa is a junior synonym for Stegana, a large cosmopolitan genus. A detailed redescription of Stegana penicillata (Kertész) new combination is provided, including new morphological information, like the male and female terminalia, the egg and a short discussion is provided about its hallmark feature.

Two closely related and distinctive species of Schistostoma Becker, i.e. Schistostoma burmanicum sp. nov. and Schistostoma foliatum sp. nov., are described from two male specimens preserved in mid-Cretaceous Burmese amber and recorded as the first known fossil representatives of this extant genus of Microphorinae. Both species possess greatly enlarged lamellate fore tibiae and modified leg chaetotaxy that are presumably male secondary sexual features. The generic limits of Schistostoma are briefly discussed and a rationale for the inclusion of these new species is provided.

Premise of the Study: An inflorescence with three pistillate flowers in amber from the early Upper Cretaceous (Turonian, ~90-94 million years ago) of central New Jersey represents the oldest known flowers with features present in an early stem complex of the Fagales. The inflorescence has characteristics of Nothofagaceae, but also has strikingly distinct characters that suggest it is intermediate between Nothofagus and other Fagales. This intermediacy is consistent with its northern hemisphere distribution., Methods: We investigated this new fossil by comparing it with extant and fossil members of the Fagales using light microscopy and nano-computed tomography. In addition, for exploring its relationships, we mapped the morphological characters onto a widely accepted molecular-based tree of modern basal Fagales using standard methods of character optimization., Key Results: The phylogenetic position of the fossil inflorescence can be unequivocally determined by the presence of unique features, singly and in combination, that are found only in "basal" members of Fagales. The fossil adds critical information on the features of the early stem Fagales, evolution of the cupule in Nothofagaceae and Fagaceae, and a reasonable biogeographic hypothesis for the differentiation of southern (e.g., Nothofagaceae) and northern hemisphere Fagales., Conclusions: This new fossil provides insight into the early evolution of Fagales and suggests that early stem Fagales that had not yet differentiated into modern families were present in the Late Cretaceous of North America. Based on available evidence, the fossil is best interpreted as an early stem member of the Fagales, with features that suggest a transition from a more generalized Nothofagus-like fagalean ancestor with some unique presumably plesiomorphic features. The presence of an enlarged perianth and flexuous styles also suggests the possibility of insect pollination, which has been lost in all Fagales with the exception of some members of subfamily Castaneoideae in Fagaceae sensu stricto (which otherwise are very different from this fossil). The poorly developed, bract-like cupule valves of the fossil can be interpreted as primitive (i.e., incipient) or as reduced from more developed cupules that are found in most modern Fagaceae and Nothofagaceae., (© 2018 Botanical Society of America.)

Study of all flies (Diptera) collected for one year from a four-hectare (150 x 266 meter) patch of cloud forest at 1,600 meters above sea level at Zurquí de Moravia, San José Province, Costa Rica (hereafter referred to as Zurquí), revealed an astounding 4,332 species. This amounts to more than half the number of named species of flies for all of Central America. Specimens were collected with two Malaise traps running continuously and with a wide array of supplementary collecting methods for three days of each month. All morphospecies from all 73 families recorded were fully curated by technicians before submission to an international team of 59 taxonomic experts for identification.        Overall, a Malaise trap on the forest edge captured 1,988 species or 51% of all collected dipteran taxa (other than of Phoridae, subsampled only from this and one other Malaise trap). A Malaise trap in the forest sampled 906 species. Of other sampling methods, the combination of four other Malaise traps and an intercept trap, aerial/hand collecting, 10 emergence traps, and four CDC light traps added the greatest number of species to our inventory. This complement of sampling methods was an effective combination for retrieving substantial numbers of species of Diptera. Comparison of select sampling methods (considering 3,487 species of non-phorid Diptera) provided further details regarding how many species were sampled by various methods.        Comparison of species numbers from each of two permanent Malaise traps from Zurquí with those of single Malaise traps at each of Tapantí and Las Alturas, 40 and 180 km distant from Zurquí respectively, suggested significant species turnover. Comparison of the greater number of species collected in all traps from Zurquí did not markedly change the degree of similarity between the three sites, although the actual number of species shared did increase.        Comparisons of the total number of named and unnamed species of Diptera from four hectares at Zurquí is equivalent to 51% of all flies named from Central America, greater than all the named fly fauna of Colombia, equivalent to 14% of named Neotropical species and equal to about 2.7% of all named Diptera worldwide. Clearly the number of species of Diptera in tropical regions has been severely underestimated and the actual number may surpass the number of species of Coleoptera.        Various published extrapolations from limited data to estimate total numbers of species of larger taxonomic categories (e.g., Hexapoda, Arthropoda, Eukaryota, etc.) are highly questionable, and certainly will remain uncertain until we have more exhaustive surveys of all and diverse taxa (like Diptera) from multiple tropical sites.        Morphological characterization of species in inventories provides identifications placed in the context of taxonomy, phylogeny, form, and ecology. DNA barcoding species is a valuable tool to estimate species numbers but used alone fails to provide a broader context for the species identified.

Estimations of tropical insect diversity generally suffer from lack of known groups or faunas against which extrapolations can be made, and have seriously underestimated the diversity of some taxa. Here we report the intensive inventory of a four-hectare tropical cloud forest in Costa Rica for one year, which yielded 4332 species of Diptera, providing the first verifiable basis for diversity of a major group of insects at a single site in the tropics. In total 73 families were present, all of which were studied to the species level, providing potentially complete coverage of all families of the order likely to be present at the site. Even so, extrapolations based on our data indicate that with further sampling, the actual total for the site could be closer to 8000 species. Efforts to completely sample a site, although resource-intensive and time-consuming, are needed to better ground estimations of world biodiversity based on limited sampling., Competing Interests: The authors declare no competing interests.

The originally published version of this Article was updated shortly after publication to add the word 'Ticks' to the title, following its inadvertent removal during the production process. This has now been corrected in both the PDF and HTML versions of the Article.

Ticks are currently among the most prevalent blood-feeding ectoparasites, but their feeding habits and hosts in deep time have long remained speculative. Here, we report direct and indirect evidence in 99 million-year-old Cretaceous amber showing that hard ticks and ticks of the extinct new family Deinocrotonidae fed on blood from feathered dinosaurs, non-avialan or avialan excluding crown-group birds. A †Cornupalpatum burmanicum hard tick is entangled in a pennaceous feather. Two deinocrotonids described as †Deinocroton draculi gen. et sp. nov. have specialised setae from dermestid beetle larvae (hastisetae) attached to their bodies, likely indicating cohabitation in a feathered dinosaur nest. A third conspecific specimen is blood-engorged, its anatomical features suggesting that deinocrotonids fed rapidly to engorgement and had multiple gonotrophic cycles. These findings provide insight into early tick evolution and ecology, and shed light on poorly known arthropod-vertebrate interactions and potential disease transmission during the Mesozoic.

Calyptrate flies include about 22,000 extant species currently classified into Hippoboscoidea (tsetse, louse, and bat flies), the muscoid grade (house flies and relatives) and the Oestroidea (blow flies, bot flies, flesh flies, and relatives). Calyptrates are abundant in nearly all terrestrial ecosystems, often playing key roles as decomposers, parasites, parasitoids, vectors of pathogens, and pollinators. For oestroids, the most diverse group within calyptrates, definitive fossils have been lacking. The first unambiguous fossil of Oestroidea is described based on a specimen discovered in amber from the Dominican Republic. The specimen was identified through digital dissection by CT scans, which provided morphological data for a cladistic analysis of its phylogenetic position among extant oestroids. The few known calyptrate fossils were used as calibration points for a molecular phylogeny (16S, 28S, CAD) to estimate the timing of major diversification events among the Oestroidea. Results indicate that: (a) the fossil belongs to the family Mesembrinellidae, and it is identified and described as Mesembrinella caenozoica sp. nov.; (b) the mesembrinellids form a sister clade to the Australian endemic Ulurumyia macalpinei (Ulurumyiidae) (McAlpine's fly), which in turn is sister to all remaining oestroids; (c) the most recent common ancestor of extant Calyptratae lived just before the K-Pg boundary (ca. 70 mya); and (d) the radiation of oestroids began in the Eocene (ca. 50 mya), with the origin of the family Mesembrinellidae dated at ca. 40 mya. These results provide new insight into the timing and rate of oestroid diversification and highlight the rapid radiation of some of the most diverse and ecologically important families of flies. ZooBank accession number-urn:lsid:zoobank.org:pub:0DC5170B-1D16-407A-889E-56EED3FE3627.

One new genus and three new species of Lygistorrhinidae in early Eocene Cambay amber from India are described, which significantly increases our knowledge about this group in the Eocene. Lygistorrhina indica n. sp. is the oldest fossil known from this extant genus. Indorrhina sahnii n. gen. et sp. shows morphological similarities to each of the two extant genera Lygistorrhina and Asiorrhina . Palaeognoriste orientale is the third species known from a group that has only been recorded from Eocene Baltic amber before. The latter finding reveals faunal links between Cambay amber and the probably slightly younger Baltic amber, adding further evidence that faunal exchange between Europe/Asia and India took place before the formation of Cambay amber., Competing Interests: The authors declare there are no competing interests.

The radiation of flowering plants in the mid-Cretaceous transformed landscapes and is widely believed to have fuelled the radiations of major groups of phytophagous insects. An excellent group to test this assertion is the scale insects (Coccomorpha: Hemiptera), with some 8,000 described Recent species and probably the most diverse fossil record of any phytophagous insect group preserved in amber. We used here a total-evidence approach (by tip-dating) employing 174 morphological characters of 73 Recent and 43 fossil taxa (48 families) and DNA sequences of three gene regions, to obtain divergence time estimates and compare the chronology of the most diverse lineage of scale insects, the neococcoid families, with the timing of the main angiosperm radiation. An estimated origin of the Coccomorpha occurred at the beginning of the Triassic, about 245 Ma [228-273], and of the neococcoids 60 million years later [210-165 Ma]. A total-evidence approach allows the integration of extinct scale insects into a phylogenetic framework, resulting in slightly younger median estimates than analyses using Recent taxa, calibrated with fossil ages only. From these estimates, we hypothesise that most major lineages of coccoids shifted from gymnosperms onto angiosperms when the latter became diverse and abundant in the mid- to Late Cretaceous.

Modern tropical forests harbor an enormous diversity of squamates, but fossilization in such environments is uncommon and little is known about tropical lizard assemblages of the Mesozoic. We report the oldest lizard assemblage preserved in amber, providing insight into the poorly preserved but potentially diverse mid-Cretaceous paleotropics. Twelve specimens from the Albian-Cenomanian boundary of Myanmar (99 Ma) preserve fine details of soft tissue and osteology, and high-resolution x-ray computed tomography permits detailed comparisons to extant and extinct lizards. The extraordinary preservation allows several specimens to be confidently assigned to groups including stem Gekkota and stem Chamaleonidae. Other taxa are assignable to crown clades on the basis of similar traits. The detailed preservation of osteological and soft tissue characters in these specimens may facilitate their precise phylogenetic placement, making them useful calibration points for molecular divergence time estimates and potential keys for resolving conflicts in higher-order squamate relationships.

A hallmark of animals that are eusocial, or those with advanced sociality, is reproductive specialization into worker and queen castes. In the most derived societies, these divisions are essentially fixed and in some arthropods, include further specialization--a tripartite system with a soldier caste that defends the colony. Eusociality has originated numerous times among insects but is believed to have appeared first in the termites (Isoptera), in the Early Cretaceous. However, all termites known from the Cretaceous have, until now, only been winged reproductives (alates and dealates); the earliest soldiers and definitive workers were known from just the Miocene (ca. 17-20 million years ago [mya]). Here, we report six termite species preserved in Early Cretaceous (ca. 100 mya) amber from Myanmar, one described as Krishnatermes yoddha gen. et sp. nov., comprising the worker/pseudergate, winged reproductive, and soldier, and a second species, Gigantotermes rex gen. et sp. nov., based on one of the largest soldier termites yet known. Phylogenetic analysis indicates that Krishnatermes are in the basal "Meiatermes-grade" of Cretaceous termites. Workers/pseudergates of another four species are briefly described, but not named. One of these workers/pseudergates reveals that ants--the most serious enemies of modern termites--lived in close proximity to termites in the Burmese paleofauna. These discoveries demonstrate the Mesozoic antiquity of specialized termite caste systems and corroborate that among all social species, termites probably had the original societies., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Across terrestrial ecosystems, modern ants are ubiquitous. As many as 94 out of every 100 individual arthropods in rainforests are ants, and they constitute up to 15% of animal biomass in the Amazon. Moreover, ants are pervasive agents of natural selection as over 10,000 arthropod species are specialized inquilines or myrmecomorphs living among ants or defending themselves through mimicry. Such impact is traditionally explained by sociality: ants are the first major group of ground-dwelling predatory insects to become eusocial, increasing efficiency of tasks and establishing competitive superiority over solitary species. A wealth of specimens from rich deposits of 99 million-year-old Burmese amber resolves ambiguity regarding sociality and diversity in the earliest ants. The stem-group genus Gerontoformica maintained distinct reproductive castes including morphotypes unknown in solitary aculeate (stinging) wasps, providing insight into early behavior. We present rare aggregations of workers, indicating group recruitment as well as an instance of interspecific combat; such aggression is a social feature of modern ants. Two species and an unusual new genus are described, further expanding the remarkable diversity of early ants. Stem-group ants are recovered as a paraphyletic assemblage at the base of modern lineages varying greatly in size, form, and mouthpart structure, interpreted here as an adaptive radiation. Though Cretaceous stem-group ants were eusocial and adaptively diverse, we hypothesize that their extinction resulted from the rise of competitively superior crown-group taxa that today form massive colonies, consistent with Wilson and Hölldobler's concept of "dynastic succession.", (Copyright © 2016 Elsevier Ltd. All rights reserved.)

A second female of mid-Cretaceous Burmaculex antiquus Borkent & Grimaldi, preserved in 99 myo Burmese amber, and the oldest known member of the Culicidae, is described in detail. Although generally opaque and distorted, some character states are added or refined. The discovery of well-developed scales on the legs shows that this feature must now be considered a synapomorphy of both the fossil and all extant members of the family. Previously described synapomorphies and further interpretation here confirm the phylogenetic position of this fossil as the sister group to extant and all known fossil Culicidae. It is placed in the new subfamily Burmaculicinae.

The great evolutionary success of angiosperms has traditionally been explained, in part, by the partnership of these plants with insect pollinators. The main approach to understanding the origins of this pervasive relationship has been study of the pollinators of living cycads, gnetaleans, and basal angiosperms. Among the most morphologically specialized living pollinators are diverse, long-proboscid flies. Early such flies include the brachyceran family Zhangsolvidae, previously known only as compression fossils from the Early Cretaceous of China and Brazil. It belongs to the infraorder Stratiomyomorpha, a group that includes the flower-visiting families Xylomyidae and Stratiomyidae. New zhangsolvid specimens in amber from Spain (ca. 105 mega-annum [Ma]) and Myanmar (100 Ma) reveal a detailed proboscis structure adapted to nectivory. Pollen clumped on a specimen from Spain is Exesipollenites, attributed to a Mesozoic gymnosperm, most likely the Bennettitales. Late Mesozoic scorpionflies with a long proboscis have been proposed as specialized pollinators of various extinct gymnosperms, but pollen has never been observed on or in their bodies. The new discovery is a very rare co-occurrence of pollen with its insect vector and provides substantiating evidence that other long-proboscid Mesozoic insects were gymnosperm pollinators. Evidence is thus now gathering that visitors and probable pollinators of early anthophytes, or seed plants, involved some insects with highly specialized morphological adaptations, which has consequences for interpreting the reproductive modes of Mesozoic gymnosperms and the significance of insect pollination in angiosperm success., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Myrmecophiles--species that depend on ant societies--include some of the most morphologically and behaviorally specialized animals known. Remarkable adaptive characters enable these creatures to bypass fortress-like security, integrate into colony life, and exploit abundant resources and protection inside ant nests. Such innovations must result from intimate coevolution with hosts, but a scarcity of definitive fossil myrmecophiles obscures when and how this lifestyle arose. Here, we report the earliest known morphologically specialized and apparently obligate myrmecophile, in Early Eocene (∼ 52 million years old) Cambay amber from India. Protoclaviger trichodens gen. et sp. nov. is a stem-group member of Clavigeritae, a speciose supertribe of pselaphine rove beetles (Coleoptera: Staphylinidae) heavily modified for myrmecophily via reduced mouthparts for trophallaxis with worker ants, brush-like trichomes that exude appeasement compounds, and fusions of many body and antennal segments. Protoclaviger captures a transitional stage in the evolutionary development of this novel body plan, most evident in its still-distinct abdominal tergites. The Cambay paleobiota marks one of the first occurrences in the fossil record of a significant presence of modern ants. Protoclaviger reveals that sophisticated social parasites were nest intruders throughout, and probably before, the ascent of ants to ecological dominance, with ancient groups such as Clavigeritae primed to radiate as their hosts became increasingly ubiquitous., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Plumage colours bestowed by carotenoid pigments can be important for visual communication and likely have a long evolutionary history within Aves. Discovering plumage carotenoids in fossil feathers could provide insight into the ecology of ancient birds and non-avian dinosaurs. With reference to a modern feather, we sought chemical evidence of carotenoids in six feathers preserved in amber (Miocene to mid-Cretaceous) and in a feather preserved as a compression fossil (Eocene). Evidence of melanin pigmentation and microstructure preservation was evaluated with scanning electron and light microscopies. We observed fine microstructural details including evidence for melanin pigmentation in the amber and compression fossils, but Raman spectral bands did not confirm the presence of carotenoids in them. Carotenoids may have been originally absent from these feathers or the pigments may have degraded during burial; the preservation of microstructure may suggest the former. Significantly, we show that carotenoid plumage pigments can be detected without sample destruction through an amber matrix using confocal Raman spectroscopy.

The occurrence of arthropods in amber exclusively from the Cretaceous and Cenozoic is widely regarded to be a result of the production and preservation of large amounts of tree resin beginning ca. 130 million years (Ma) ago. Abundant 230 million-year-old amber from the Late Triassic (Carnian) of northeastern Italy has previously yielded myriad microorganisms, but we report here that it also preserves arthropods some 100 Ma older than the earliest prior records in amber. The Triassic specimens are a nematoceran fly (Diptera) and two disparate species of mites, Triasacarus fedelei gen. et sp. nov., and Ampezzoa triassica gen. et sp. nov. These mites are the oldest definitive fossils of a group, the Eriophyoidea, which includes the gall mites and comprises at least 3,500 Recent species, 97% of which feed on angiosperms and represents one of the most specialized lineages of phytophagous arthropods. Antiquity of the gall mites in much their extant form was unexpected, particularly with the Triassic species already having many of their present-day features (such as only two pairs of legs); further, it establishes conifer feeding as an ancestral trait. Feeding by the fossil mites may have contributed to the formation of the amber droplets, but we find that the abundance of amber during the Carnian (ca. 230 Ma) is globally anomalous for the pre-Cretaceous and may, alternatively, be related to paleoclimate. Further recovery of arthropods in Carnian-aged amber is promising and will have profound implications for understanding the evolution of terrestrial members of the most diverse phylum of organisms.

Flies are one of four superradiations of insects (along with beetles, wasps, and moths) that account for the majority of animal life on Earth. Diptera includes species known for their ubiquity (Musca domestica house fly), their role as pests (Anopheles gambiae malaria mosquito), and their value as model organisms across the biological sciences (Drosophila melanogaster). A resolved phylogeny for flies provides a framework for genomic, developmental, and evolutionary studies by facilitating comparisons across model organisms, yet recent research has suggested that fly relationships have been obscured by multiple episodes of rapid diversification. We provide a phylogenomic estimate of fly relationships based on molecules and morphology from 149 of 157 families, including 30 kb from 14 nuclear loci and complete mitochondrial genomes combined with 371 morphological characters. Multiple analyses show support for traditional groups (Brachycera, Cyclorrhapha, and Schizophora) and corroborate contentious findings, such as the anomalous Deuterophlebiidae as the sister group to all remaining Diptera. Our findings reveal that the closest relatives of the Drosophilidae are highly modified parasites (including the wingless Braulidae) of bees and other insects. Furthermore, we use micro-RNAs to resolve a node with implications for the evolution of embryonic development in Diptera. We demonstrate that flies experienced three episodes of rapid radiation--lower Diptera (220 Ma), lower Brachycera (180 Ma), and Schizophora (65 Ma)--and a number of life history transitions to hematophagy, phytophagy, and parasitism in the history of fly evolution over 260 million y.

The family Scelembiidae (Neoembiodea: Embiomorpha: Archembioidea) is recorded from Asia for the first time, based on two individuals preserved in Early Eocene amber from the Cambay Basin, western India. Kumarembia hurleyi Engel & Grimaldi, gen. n. et sp. n., is described, figured, and distinguished from other archembioid genera. The genus shares male genitalic features with scelembiids, otherwise known from South America and Africa.

Thirteen species of basal Brachycera (11 described as new) are reported, belonging to nine families and three infraorders. They are preserved in amber from the Early Cretaceous (Neocomian) of Lebanon, Albian of northern Spain, upper Albian to lower Cenomanian of northern Myanmar, and Late Cretaceous of New Jersey USA (Turonian) and Alberta, Canada (Campanian). Taxa are as follows, with significance as noted: In Stratiomyomorpha: Stratiomyidae (Cretaceogaster pygmaeus Teskey [2 new specimens in Canadian amber], Lysistrata emerita Grimaldi & Arillo, gen. et sp. n. [stem-group species of the family in Spanish amber]), and Xylomyidae (Cretoxyla azari Grimaldi & Cumming, gen. et sp. n. [in Lebanese amber], and an undescribed species from Spain). In Tabanomorpha: Tabanidae (Cratotabanus newjerseyensis Grimaldi, sp. n., in New Jersey amber). In Muscomorpha: Acroceridae (Schlingeromyia minuta Grimaldi & Hauser, gen. et sp. n. and Burmacyrtus rusmithi Grimaldi & Hauser gen. etsp. n., in Burmese amber, the only definitive species of the family from the Cretaceous); Mythicomyiidae (Microburmyia analvena Grimaldi & Cumming gen. et sp. n. and Microburmyia veanalvena Grimaldi & Cumming, sp. n., stem-group species of the family, both in Burmese amber); Apsilocephalidae or near (therevoid family-group) (Kumaromyia burmitica Grimaldi & Hauser, gen. et sp. n. [in Burmese amber]); Apystomyiidae (Hilarimorphites burmanica Grimaldi & Cumming, sp. n. [in Burmese amber], whose closest relatives are from the Late Jurassic of Kazachstan, the Late Cretaceous of New Jersey, and Recent of California). Lastly, two species belonging to families incertae sedis, both in Burmese amber: Tethepomyiidae (Tethepomyia zigrasi Grimaldi & Arillo sp. n., the aculeate oviscapt of which indicates this family was probably parasitoidal and related to Eremochaetidae); and unplaced to family is Myanmyia asteiformia Grimaldi, gen. et sp. n., a minute fly with highly reduced venation. These new taxa significantly expand the Mesozoic fossil record of rare and phylogenetically significant taxa of lower Brachycera.

The fauna of termites (Isoptera) preserved in Early Eocene amber from the Cambay Basin (Gujarat, India) are described and figured. Three new genera and four new species are recognized, all of them Neoisoptera - Parastylotermes krishnai Engel & Grimaldi, sp. n. (Stylotermitidae); Prostylotermes kamboja Engel & Grimaldi, gen. et sp. n. (Stylotermitidae?); Zophotermes Engel, gen. n., with Zophotermes ashoki Engel & Singh, sp. n. (Rhinotermitidae: Prorhinotermitinae); and Nanotermes isaacae Engel & Grimaldi, gen. et sp. n. (Termitidae: Termitinae?). Together these species represent the earliest Tertiary records of the Neoisoptera and the oldest definitive record of Termitidae, a family that comprises >75% of the living species of Isoptera. Interestingly, the affinities of the Cambay amber termites are with largely Laurasian lineages, in this regard paralleling relationships seen between the fauna of bees and some flies. Diversity of Neoisoptera in Indian amber may reflect origin of the amber deposit in Dipterocarpaceae forests formed at or near the paleoequator.

Identifying the unambiguous sister group to the hexapods has been elusive. Traditional concepts include the Myriapoda (the Tracheata/Atelocerata hypothesis), but recent molecular studies consistently indicate it is the Crustacea, either in part or entirety (the Pancrustacea/Tetraconata hypothesis). The morphological evidence in support of Tracheata is reviewed, and most features are found to be ambiguous (i.e., losses, poorly known and surveyed structures, and probable convergences), though some appear to be synapomorphic, such as tentorial structure and the presence of styli and eversible vesicles. Other morphological features, particularly the structure of the eyes and nervous system, support Pancrustacea, as does consistent molecular evidence (which is reviewed and critiqued). Suggestions are made regarding hexapod-crustacean limb homologies. Relationships among basal (apterygote) hexapods are reviewed, and critical Paleozoic fossils are discussed. Despite the scarceness of Devonian hexapods, major lineages like Collembola and even dicondylic Insecta appeared in the Early Devonian; stem-group and putative Archaeognatha are known from the Carboniferous through Permian and the Late Devonian, respectively. Thus, the earliest divergences of hexapods were perhaps Late Silurian, which is considerably younger than several estimates made using molecular data., (Copyright (c) 2009. Published by Elsevier Ltd.)

Among insects, eusocial behavior occurs in termites, ants, some bees and wasps. Isoptera and Hymenoptera convergently share social behavior, and for both taxa its evolution remains poorly understood. While dating analyses provide researchers with the opportunity to date the origin of eusociality, fossil calibration methodology may mislead subsequent ecological interpretations. Using a comprehensive termite dataset, we explored the effect of fossil placement and calibration methodology. A combined molecular and morphological dataset for 42 extant termite lineages was used, and a second dataset including these 42 taxa, plus an additional 39 fossil lineages for which we had only morphological data. MrBayes doublet-model analyses recovered similar topologies, with one minor exception (Stolotermitidae is sister to the Hodotermitidae, s.s., in the 42-taxon analysis but is in a polytomy with Hodotermitidae and (Kalotermitidae + Neoisoptera) in the 81-taxon analysis). Analyses using the r8s program on these topologies were run with either minimum/maximum constraints (analysis a = 42-taxon and analysis c = 81-taxon analyses) or with the fossil taxon ages fixed (ages fixed to be the geological age of the deposit from which they came, analysis b = 81-taxon analysis). Confidence intervals were determined for the resulting ultrametric trees, and for most major clades there was significant overlap between dates recovered for analyses A and C (with exceptions, such as the nodes Neoisoptera, and Euisoptera). With the exception of isopteran and eusiopteran node ages, however, none of the major clade ages overlapped when analysis B is compared with either analysis A or C. Future studies on Dictyoptera should note that the age of Kalotermitidae was underestimated in absence of kalotermitid fossils with fixed ages., (Copyright (c) 2009 Elsevier Ltd. All rights reserved.)

The orb web is a spectacular evolutionary innovation that enables spiders to catch flying prey. This elegant, geometric structure is woven with silk fibers that are renowned for their superior mechanical properties. We used silk gland expression libraries to address a long-standing controversy concerning the evolution of the orb-web architecture. Contrary to the view that the orb-web design evolved multiple times, we found that the distribution and phylogeny of silk proteins support a single, ancient origin of the orb web at least 136 million years ago. Furthermore, we substantially expanded the repository of silk sequences that can be used for the synthesis of high-performance biomaterials.

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.

Six species of Drosophila were tested for tolerance to the mushroom toxin alpha-amanitin, a potent inhibitor of RNA polymerase II. Three nonmycophagous species-D. melanogaster, D. immigrans, and D. pseudoobscura-showed very low survival and long development times in the presence of amanitin. Three mycophagous species-D. putrida, D. recens, and D. tripunctata-showed little or no sensitivity. Analysis in vitro indicated that this tolerance is not based on alteration of the molecular structure of RNA polymerase II.

Trigona prisca, a stingless honey bee (Apidae; Meliponinae), is reported from Cretaceous New Jersey amber (96-74 million years before present). This is about twice the age of the oldest previously known fossil bee, although Trigona is one of the most derived bee genera. T. prisca is closely similar to modern neotropical species. Most of bee evolution probably occurred during the approximately 50 million years between the beginning of the Cretaceous when flowering plants (on which bees depend) appeared and the time of T. prisca. Since then, in this phyletic line of Meliponinae, there has been almost no morphological evolution. Since the fossil is a worker, social organization had arisen by its time.