Neorhinoleucophenga Duda, 1924, has been known for a century just on the basis of several types, two of them putatively lost. The type species, N. vitripennis Duda, was designated by Wheeler (1970). For the present study, the type of vitripennis (which was not lost) was studied along with several new specimens, all from Costa Rica, and the species is shown to belong to Zygothrica Wiedmann, thus Zygothrica vitripennis, new combination, is proposed. The remaining species, N. trachyopa Duda, is subsequently designated as the type species, and defining differences between it and four other new species are based on restudy of its type (it also was not lost). New material from Costa Rica and Venezuela allowed a detailed morphological study of the genus, which is in the subfamily Drosophilinae (not Steganinae); species are highly modified, including the unique presence of a large, setose gland on the hind femur. Of the five species four are new: Neorhinoleucophenga frontalis, n. sp., lepida, n. sp., nectandra, n. sp., and priapos, n. sp. The genus appears restricted to cool, wet, montane neotropical forests. One species (N. lepida) was found aggregating with a pyraloid caterpillar in rolled leaves in Venezuela, perhaps attracted to the frass. Synapomorphic morphological characters are presented for a close relationship of Neorhinoleuphenga and Laccodrosophila Duda, the latter breeding in flowers. An identification key to the species of Neorhinoleucophenga is provided.

Among the many diverse traits of insects, the most speciose and successful terrestrial animals, is an incredible range of lifespans. While some are quite long-lived, such as cicadas (years as larvae) or termite queens (decades as adults), many insects, such as mayflies (Insecta: Ephemeroptera), have exceedingly short adult lifespans that serve essentially just for mating and selecting oviposition sites, foregoing feeding to reproduce as quickly as possible. This behavior is correlated with mouthparts that are highly reduced or even absent, and the alimentary system is converted into an air-filled space, possibly non-functional for digestion. The order-wide phenomenon of the co-opted gut is found in only one other group, the twisted-wing parasites (Insecta: Strepsiptera). Here, we present micro-CT scans and volume measurements (body and alimentary air) that reveal a previously undocumented inflated alimentary system in non-feeding species from five additional insect orders: Plecoptera, Embioptera, Megaloptera, Lepidoptera, and Diptera. The association between reduction or complete loss of adult feeding and a large volume of air in the gut is statistically highly significant. The reduction of mouthparts in these taxa reflects non-feeding in adults, indicating that convergence of this trait with alimentary inflation probably has adaptive functions. We discuss several, nonexclusive ways in which an inflated alimentary system can be adaptive for adult insects.

of the Asian species Drosophila (Psilodorha) ancora Okada, 1968, recently placed into Dichaetophora s.l., have sclerites on the labellum that have grown into a pair of mandible-like structures. Psilodorha Okada, closely related to a complex of genera from the Old World tropics and subtropics, including Dichaetophora, is elevated to genus from a subgenus of Drosophila. Here, two new closely related species from the Philippines are described with more elaborate "mandibles", Psilodorha mandibula sp. nov. and P. forceps sp. nov. Male mouthparts are described in detail and a discussion provided for their possible coercive, sexual function: biting and grasping of the female oviscapt during courtship to induce receptivity.

new species of the nearly worldwide genus Aulacigaster are described based on specimens preserved in Late Miocene amber (15-17 million years n. sp., A. mathisi n. sp., and A. rungae n. sp. Details of the male terminalia of A. neoleucopeza are provided as a comparison to three of the fossil species. Commentary is provided on morphological characters pertaining to aulacigastrid relationships. All the fossil Aulacigaster belong to the A. leucopeza group, which today predominates in the Holarctic Region, Africa and Asia, with only a few of the 42 Neotropical species in the genus belonging to the group. No leucopeza-group species are known from the Caribbean, so the fossils probably represent significant extinction in the region.

Flies in the Drosophila (Sophophora) obscura species group are among the most common native drosophilids in northern temperate and boreal forests; southward, into cool, montane tropical forests they are rare and localized, but diverse. Of the world's 48 species, 18 occur in the New World, including three new neotropical species described here. Here, all New World species are diagnosed, many with images and the use of some new morphological features such as female terminalia (oviscapt and spermathecal structure). A basic phylogenetic scheme of relationships based on 19 morphological characters corresponds well with molecular trees. Type series have been rediscovered of D. algonquin, athabasca, azteca, narragansett, and seminole (all described by Sturtevant and Dobzhansky in 1936), from which a lectotype is designated for each of the first four species and the holotype is recognized for seminole. Drosophila narragansett from the eastern United States, which has been found only once in 60 years, is redescribed in detail from historical material; D. seminole is found to be a synonym of narragansett. The three new species are Drosophila chibcha, n. sp. (from Costa Rica to Venezuela and Peru), D. olmeca, n. sp. (from southern Mexico), both of these in the affinis subgroup; and D. zapoteca, n. sp. (from Guatemala), in the pseudoobscura subgroup. Significant new distributional and host records are reported for various species.

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.

Known from over 50 Triassic localities worldwide, beetles were a significant component of the early Mesozoic paleofauna. Beetle fossils are particularly diverse in the Late Triassic (Norian) Cow Branch and Walnut Cove formations (Solite deposit) of Virginia and North Carolina, with 100 distinct morphotypes sorted from approximately 1000 specimens. The diversity of the Solite Coleoptera is documented, the 100 beetle morphotypes are informally described, and comparisons are made with other beetle communities through geologic time. In comparison with modern beetle communities, the Solite fauna shares two remarkable similarities. First, the distribution of Solite beetle body sizes matches that of some modern beetle communities, with the majority of specimens in both groups measuring between 2 and 4 mm in length. Second, the vast majority of the 100 Solite morphotypes (84%) are known from only a single specimen. This pattern somewhat follows the species abundance distribution of modern animal communities, in which a community is comprised of only a few common species and many rare species. In contrast, the Solite beetle fauna differs markedly from those of other Triassic and Early Jurassic deposits, both in the composition of higher taxa present, as well as in the lack of shared taxa between sites. The uniqueness of the Solite taxa, including the remarkable diversity, demonstrate the importance of the Solite Konservat-Lagerstatte in understanding the evolutionary history of Order Coleoptera.

Pleurothallidinae is the most diverse Neotropical subtribe in Orchidaceae and is almost exclusively pollinated by insects of the order Diptera. Dracula, a genus of 138 species in the Pleurothallidinae, is known to attract Zygothrica (Drosophilidae) flies, common macrofungi visitors, by imitating fungal volatile compounds and lamellae. Interestingly, Dracula orchids do not appear to offer any rewards to their floral visitors. While brood-site imitation of macrofungi has been suggested as their pollination system, the exact behaviour of flies during their extended visits to the orchid flowers has yet to be confirmed. In this study, we document the pollination mechanism of Dracula erythrochaete. We characterize the floral structures involved in the mechanism using anatomical and morphological evidence. Additionally, through in situ observations and camera recordings, we describe the insect behaviour. We show that flowers of D. erythrochaete share the same group of visitors as nearby macrofungi, including different Zygothrica species, seven of which were determined as effective pollinators. Male and female flies were attracted to the flowers and displayed feeding behaviour. Accordingly, proteins were detected in high concentrations on the papillae at the base of the movable lip and in papillary trichomes of the sepals, near the column. The concept of brood-site imitation is debated, as no oviposition events were observed and no eggs were found on the flowers. Therefore, a mixed strategy of congregation/brood-site imitation and food reward is proposed for pollination.

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.

Amber is fossilized resin that preserves biological remains in exceptional detail, study of which has revolu-tionized understanding of past terrestrial organisms and habitats from the Early Cretaceous to the present day. Cretaceous amber outcrops are more abundant in the Northern Hemisphere and during an interval of about 54 million years, from the Barremian to the Campanian. The extensive resin production that generated this remarkable amber record may be attributed to the biology of coniferous resin producers, the growth of resin-iferous forests in proximity to transitional sedimentary environments, and the dynamics of climate during the Cretaceous. Here we discuss the set of interrelated abiotic and biotic factors potentially involved in resin pro-duction during that time. We name this period of mass resin production by conifers during the late Mesozoic, fundamental as an archive of terrestrial life, the 'Cretaceous Resinous Interval' (CREI).

ABSTRACT The highest single-site species diversity known thus far in the world for Drosophilidae is in Costa Rica, based on findings in this report. A total of 352 species of Drosophilidae (Diptera) were found in a cloud forest (1580 m) in Zurquí de Moravia, San José Province (hereafter “Zurquí”), based on 2908 specimens collected continuously for one year, using eight trapping and collecting methods. There are currently 305 described species from Costa Rica. Zurquí is at the edge of a large, protected area and was the site of an All-Diptera inventory project. For this study, drosophilid specimens were identified to genus/subgenus, sorted to morphospecies, and their abundances plotted by collection method: Malaise traps, flight intercept traps, baited traps, light and yellow pan traps, emergence traps, and hand collecting with nets. The standard method used by drosophilists, bait trapping, captured a small fraction of species. Malaise traps captured 87% of all species, and 41% of the 352 species were captured only this way. Emergence traps captured a surprising diversity (47 species) of Diathoneura and Drosophila, establishing that leaf litter/humus is an important breeding site for some taxa. Combining all collection methods, 11 species were abundant, as defined by 50 or more specimens, and comprised 35% of all specimens in the study; two-thirds (66%) of all species were rare, as defined by five or fewer specimens. Comparisons are made to other well-collected sites and regions around the world. Lowland to mid-montane forests on the eastern slopes of the Andes may be the most diverse area for Drosophilidae, a family that is exemplary for studying the ecology and evolution of tropical diversity.

A broad comparative study of insect respiratory morphology is presented. Tracheae, epidermal invaginations extending into the body in branching networks of tubes, supply tissues with direct access to air for gas exchange. While previous tracheal studies focused on a handful of taxa and lacked in consistency, here a unified system of tracheal nomenclature is established using visualizations from micro-CT scanning of representatives from apterygotes, Paleoptera, and Polyneoptera, totaling 29 species, 29 genera, and 26 families in 13 insect orders. Three-dimensional visualizations of named tracheal branches establish robust assessments of homology and provide a framework for further studies across class Insecta. Patterns in respiratory architecture are presented along with a discussion of future investigations into phylogenetic and physiological questions.

A distinctive species in the family Drosophilidae, Drosophila ancora Okada, 1968, is redescribed from specimens from Vietnam, and transferred to the genus Dichaetophora Duda sensu lato. It is exceptional among Diptera for its labellar sclerites that in males have grown into a pair of heavily sclerotized, pointed lobes at the tip of the labellum, producing what appear to be chewing mandibles. This is analogous to the condition in the dolichopodid Melanderia Aldrich, but there it is not sexually dimorphic. The structures are doubtfully used in male-male aggression or in postcopulatory mate guarding. Based on their shapes and fit, it is proposed that the “mandibles” are used by males to grasp the tip of the female oviscapt during courtship or for the male to grasp the female wing edge while mounted.

Diplura are an ancient group of basal (apterygote) hexapods that thrive in various cryptic terrestrial habitats. Despite an ancient origin that extends at least to the Devonian period, the dipluran fossil record is exceedingly sparse. Here, we document five very rare fossil specimens of the family Campodeidae in amber from the Miocene of the Dominican Republic and the Eocene of the Baltic region. Microscopic preservation in amber provides unique detail for taxonomic placement of small, delicate, soil- and leaf litter-dwelling organisms like these. New taxa include the following: in Lepidocampinae, Lepidocampa glaesi sp. nov. (in Dominican amber); and in Campodeinae, Litocampa eobaltica sp. nov. (in Baltic amber) and Rostricampa engeli gen. et sp. nov. (in Dominican amber). Rostricampa has an extraordinary rostrum formed by sclerotized extensions of the clypeus and, probably, the labium, unique among diplurans. These new taxa provide rare additional data on the fossil record of the earliest diverging lineages of the hexapods and shed light on their evolution and ecology.

Diplurans are among the earliest hexapods in the geological record. These primitively wingless relatives of insects are infrequently encountered despite being pervasive in soil habitats. Two groups have disparate adaptations for hunting, one mechanical and the other chemical, in Japygoidea and Projapygoidea, respectively. Here, we report three genera (two new) and four species of fossil Projapygidae preserved in Mesozoic and Cenozoic ambers: Electroprojapyx alchemicus gen. et sp. nov. in mid-Cretaceous Myanmar amber, and Symphylurinopsis punctatus gen. et sp. nov. and two species (unnamed) of Symphylurinus in Miocene Dominican amber. The exceptionally preserved specimens possess cerci that are morphologically specialized for expelling a glandular substance on prey. The new Cretaceous E. alchemicus is a stem group to all living species of the family and provides conclusive Mesozoic evidence for a rare type of predation involving offensive (vs. defensive) secretions. The specimen was fossilized in a preying-and-spraying position with its presumptive meal, a Symphypleona springtail (Collembola), reflecting the behavioural predatory repertoire of modern relatives. Apart from one Cenozoic species, these rare specimens represent the only fossil record of the family Projapygidae. Our findings demonstrate that these basal hexapods were predators of small arthropods of ancient forest soils and enrich our understanding of palaeoecological associations and behavioural strategies paramount for the survival of species.

Thorough biotic inventories are still needed even in families with paradigm organisms like Drosophilidae, including well-studied areas such as North America. This work presents a taxonomic revision of the species of the genus Amiota Loew in North America and the Nearctic portion of Mexico. Amiota steganoptera Malloch is currently excluded from the Nearctic and Amiota setigera Malloch is synonymized under Amiota humeralis Loew. Specimens of Amiota subtusradiata Duda were not encountered during this study along with its synonym Amiota quadrata Takada and Toda; however, based on previous descriptions we include A. subtusradiata in the Nearctic fauna. All other previously described species from the Nearctic are redescribed. Thirty-six species are described as new: Amiota amputata, A. antitormentum, A. avipes, A. biacuminis, A. brayi, A. byersi, A. cervites, A. cruciatum, A. didens, A. durangoensis, A. elsaltoensis, A. floridiensis, A. forceps, A. fulvitibia, A. hyalou, A. imperator, A. incurva, A. laevifurca, A. latilabrum, A. mcalpinei, A. multiplex, A. nanonigrescens, A. occidentalis, A. onyx, A. oviraptor, A. pseudominor, A. raripennis, A. sinaloensis, A. subnebojsa, A. tessae, A. texas, A. tibialis, A. tormentum, A. uniacuminis, A. wheeleri, and A. zaliskoi. This increases the total species known in the Nearctic from 13 to 49. All species in the Nearctic are illustrated, adult diagnostic features are discussed, and distributions are provided. A cladogram based on parsimony analysis of 46 morphological characters established species groups in the genus. Most of the Nearctic species were accommodated into 10 species groups. Three species groups were previously erected for species in China and Europe. Seven species groups are newly established: the avipes, cervites, hsui, mariae, nebojsa, nigrescens, and subtusradiata groups. Diversity in Amiota appears to be partially dependent on elevation and latitude in the Nearctic, with high diversity found in southern Ontario, the Appalachians, the Ozarks, mountain forests of Arizona and New Mexico, and the Sierra Madre of central Mexico. The taxonomic history of the Nearctic species is reviewed, and various aspects of their biology is presented. Males of species in the A. mariae species group are polymorphic for mirror-image, asymmetric genitalia, called chiral variants. Besides morphology, larval saproxyly, adult lachryphagy, and biogeography are reviewed. Challenges to the study of Amiota and future prospects are discussed.

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 similar to 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.