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While the monophyly of winged insects (Pterygota) is well supported, phylogenetic relationships among the most basal extant pterygote lineages are problematic. Ephemeroptera (mayflies) and Odonata (dragonflies) represent the two most basal extant lineages of winged insects, and determining their relationship with regard to Neoptera (remaining winged insects) is a critical step toward understanding insect diversification. A recent molecular analysis concluded that Paleoptera (Odonata + Ephemeroptera) is monophyletic. However, we demonstrate that this result is supported only under a narrow range of alignment parameters. We have further tested the monophyly of Paleoptera using additional sequence data from 18SrDNA, 28S rDNA, and Histone 3 for a broader selection of taxa and a wider range of analytical methodologies. Our results suggest that the current suite of molecular data ambiguously resolve the three basal winged insect lineages and do not provide independent confirmation of Odonata + Neoptera as supported via morphological data.

The earliest branching event in winged insects, one of the core problems regarding early insect evolution, was addressed using characters of the head. The head is arguably one of the most complex body regions in insects and the phylogenetic information content of its features has been demonstrated. In contrast, the wings and other body parts related to the flight apparatus and sperm transmission are not useful in the context of this problem, as the outgroups (silverfish and bristletails) are wingless and transmit spermatophores externally. Therefore, they show profound differences in the organization of the postcephalic body, and assessment of homology and subsequent phylogenetic analysis of features of these body regions is extremely difficult. The core of this study is the investigation of head structures of representatives of the major clades of dragonflies. A detailed description of the head of Lestes virens is presented and was used as a starting point for the compilation of a character set and a character state matrix for the entire Dicondylia (winged insects + silverfish), with a main focus on the placement of dragonflies and consequently the basal branching event within winged insects. Our results indicate a sister-group relationship between a clade Palaeoptera (dragonflies + mayflies) and the megadiverse monophyletic lineage Neoptera. We show that despite considerable structural similarity between the odonate and neopteran mandible, the muscle equipment in dragonflies is more plesiomorphic with respect to Dicondylia than previously known. Odonata and Ephemeroptera also share presumably derived features of the antenna, maxilla, and labial musculature. Parsimony analyses of the head data unambiguously support a clade Palaeoptera. � The Willi Hennig Society 2012.

Background The phylogenetic relationships of Odonata (dragonflies and damselflies) and Ephemeroptera (mayflies) remain unresolved. Different researchers have supported one of three hypotheses (Palaeoptera, Chiastomyaria or Metapterygota) based on data from different morphological characters and molecular markers, sometimes even re-assessing the same transcriptomes or mitochondrial genomes. The appropriate choice of outgroups and more taxon sampling is thought to eliminate artificial phylogenetic relationships and obtain an accurate phylogeny. Hence, in the current study, we sequenced 28 mt genomes from Ephemeroptera, Odonata and Plecoptera to further investigate phylogenetic relationships, the probability of each of the three hypotheses, and to examine mt gene arrangements in these species. We selected three different combinations of outgroups to analyze how outgroup choice affected the phylogenetic relationships of Odonata and Ephemeroptera. Methods Mitochondrial genomes from 28 species of mayflies, dragonflies, damselflies and stoneflies were sequenced. We used Bayesian inference (BI) and Maximum likelihood (ML) analyses for each dataset to reconstruct an accurate phylogeny of these winged insect orders. The effect of outgroup choice was assessed by separate analyses using three outgroups combinations: (a) four bristletails and three silverfish as outgroups, (b) five bristletails and three silverfish as outgroups, or (c) five diplurans as outgroups. Results Among these sequenced mitogenomes we found the gene arrangement IMQM in Heptageniidae (Ephemeroptera), and an inverted and translocated tRNA-Ile between the 12S RNA gene and the control region in Ephemerellidae (Ephemeroptera). The IMQM gene arrangement in Heptageniidae (Ephemeroptera) can be explained via the tandem-duplication and random loss model, and the transposition and inversion of tRNA-Ile genes in Ephemerellidae can be explained through the recombination and tandem duplication-random loss (TDRL) model. Our phylogenetic analysis strongly supported the Chiastomyaria hypothesis in three different outgroup combinations in BI analyses. The results also show that suitable outgroups are very important to determining phylogenetic relationships in the rapid evolution of insects especially among Ephemeroptera and Odonata. The mt genome is a suitable marker to investigate the phylogeny of inter-order and inter-family relationships of insects but outgroup choice is very important for deriving these relationships among winged insects. Hence, we must carefully choose the correct outgroup in order to discuss the relationships of Ephemeroptera and Odonata.

International audience; A new dictyoneurid insect, Dictyoneura goujonorum n. sp. from the Latest Ghzelian-Asselian basin of Graissessac (Hérault, France) is described in details. It is represented by a wellpreserved specimen with wings of 32-35 mm long and 13-14 mm wide and other peculiar diagnostic characters such a MP with four branches and a CuP with three branches. As all the other Dictyoneura species are known from the Namurian and/or the Wesphalian, Dictyoneura goujonorum n. sp. is the youngest representative of the genus. It is also the first record of the order Palaeodictyoptera from the Graissessac basin. The Carboniferous-Permian palaeodictyopterans are well-known to have lived in rather humid swamp forests. The global warming and drying of the climate during the Permian and/or the rise of potential predators may be responsible of their extinction.

International audience; Anhuihymen medianelongata Huang and Nel, gen. nov. et sp. nov., first accurate Chinese Protohymenidae, is described from the Middle Permian Yinping Formation at Chaohu, Anhui Province, Southern China. This region was under a warm and humid climate and separated from the drier Laurussia by the paleo-Thetys ocean during the Middle Permian. This discovery shows that this group was probably very widely distributed during the Permian, and adapted to very different climates and biotas. It also confirms that our current knowledge on the Permian fossil insects is very fragmentary.

A new species of ‘Megasecoptera-like’ insect, Sinodiapha ramosa gen. and sp. nov., is described based on two specimens from the Xiaheyan locality (early Pennsylvanian) of China, one of which displa...

No consensus exists for the homology and terminology of the male genitalia of the Hexapoda despite over a century of debate. Based on dissections and the literature, genital skeletomusculature was compared across the Hexapoda and contrasted with the Remipedia, the closest pancrustacean outgroup. The pattern of origin and insertion for extrinsic and intrinsic genitalic musculature was found to be consistent among the Ectognatha, Protura, and the Remipedia, allowing for the inference of homologies given recent phylogenomic studies. The penis of the Hexapoda is inferred to be derived from medially-fused primary gonopods (gonopore-bearing limbs), while the genitalia of the Ectognatha are inferred to include both the tenth-segmental penis and the ninth-segmental secondary gonopods, similar to the genitalia of female insects which comprise gonopods of the eighth and ninth segments. A new nomenclatural system for hexapodan genitalic musculature is presented and applied, and a general list of anatomical concepts is provided. Novel and refined homologies are proposed for all hexapodan orders, and a series of groundplans are postulated. Emphasis is placed on the Endopterygota, for which fine-grained transition series are hypothesized given observed skeletomuscular correspondences.

The structure of insect wing articulation is considered as reliable source of high level characters for phylogenetic analyses. However, the correct identification of homologous structures among the main groups of Pterygota is a hotly debated issue. Therefore, the reconstruction of the wing bases in Paleozoic extinct relatives is of great interest, but at the same time it should be treated with extreme caution due to distortions caused by taphonomic effects. The present study is focused on the wing base in Dunbaria (Spilapteridae). The articulation in Dunbaria quinquefasciata is mainly formed by a prominent upright axillary plate while the humeral plate is markedly reduced. Due to unique preservation of surface relief of the axillary plate, its composition shows a detailed pattern of three fused axillary sclerites and presumable position of the sclerite 3Ax. The obtained structures were compared among Spilapteridae and to other palaeodictyopterans Ostrava nigra (Homoiopteridae) and Namuroningxia elegans (Namuroningxiidae). The comparative study uncovered two patterns of 3Ax in Dunbaria and Namuroningxia, which correspond to their different suprafamilial classification. In contrast to previous studies these new results reveal the homologous structural elements in the wing base between Paleozoic Palaeodictyoptera and their extant relatives of Ephemeroptera, Odonata and Neoptera.

The impacts of the modern, agrochemicals based agriculture that threatens the overall systems sustainability, need to be monitored and evaluated. Seeking for agroecosystems monitors, the present article focus in the occurrence and abundance of aquatic macroinvertebrates, that have been frequently used as bioindicators of water quality due to their relationship with land use. Some of these organisms are on the top of the food chain, where bioaccumulation and biomagnification processes can be observed, and they can turn into secondary pollution sources of systems and terrestrial organisms as well. Odonate nymphs, which belong to the functional group of predators, were selected for this study. A methodology to determine 73 pesticide residues in odonate nymphs by LC-MS/MS and GC-MS/MS was developed. A QuEChERS sample preparation strategy was adapted. As it is complex to obtain samples especially in disturbed ecosystems, the method was minimized to a sample size of 200mg of fresh nymphs. The method was validated and good recoveries (71-120%) with RSDs below 20% for the majority of the studied pesticides at least at two of the assayed levels 1, 10 and 50µgkg-1 were obtained. For 32 analytes the limit of quantitation was 1µgkg-1 and 10µgkg-1 for the others. The lineal range was observed between 1-100µgkg-1 in matrix-matched and solvent calibration curves for most of the assessed pesticides. LC-MS/MS matrix effects were evaluated, 40% of the analytes presented low or no signal suppression. Only flufenoxuron presented high matrix effects. The obtained methodology is adequate for pesticide multiresidue analysis in aquatic macroinvertebrates (odonates) aiming to contribute to the ecological state evaluation of freshwater ecosystems.

Insects are the most diverse animal group, with 1 million species described. This success is due in part to their long evolutionary history, as they emerged about 475 Mya, as well as to their different morphophysiological innovations. A key innovation was the emergence of wings about 410 Mya. Another one was metamorphosis, which occurred practically simultaneously to the emergence of wings. Wingless (apterygote) insects are ametabolan; that is, they do not change during the postembryonic development. In contrast, winged (pterygote) insects undertake metamorphosis. In the early-branching pterygotes (Palaeoptera, Polyneoptera, and Paraneoptera superorders), the developmental mode is categorized as hemimetaboly and comprises three stages: the embryo, the juvenile instars or nymphs, and the adult, which is similar to the nymphs. In the superorder Endopterygota, which emerged some 370 Mya, the developmental mode is categorized as holometaboly and comprises four stages: the embryo, the juvenile instars or larvae, the pupa, and the adult, which is different from the larvae. Thus the pupa bridges the gap between the larvae and the adult. The embryogenesis of all insects includes the essential steps of syncytial cleavage, germ band and blastoderm formation, differentiation of the ectoderm, mesoderm, and endoderm, and organogenesis. However, embryo development of ametabolan, hemimetabolan, and holometabolan species differ each other in significant details, such the number of cuticles deposited, the type of germ band, the complexity of blastokinesis, and peculiarities of the organogenesis.

The series of two fossil species belonging to the order Palaeodictyoptera from the Late Carboniferous of Kuznetsk Basin in Russia were re-examined. The two species as Tchirkovaea guttata and Paimbia fenestrata were investigated with emphasis on the wing growth and development in comparison with the structure of developing wings in recent mayflies. This fossil material of T. guttata and P. fenestrata was long considered by previous authors as undisputed evidence for a unique type of wing development in the Palaeozoic insects. The idea was that the larvae of these insects possessed the wings, which became articulated and fully movable already earlier during the postembryonic development and that these gradually growing wings changed their position from longitudinal to perpendicular to the body axis. Moreover, the development was supposed to include two or more subimaginal instars, implying that the fully winged instars moulted several times during postembryonic development. After detailed study of the available fossils and subsequent comparison of the fossil evidence with the development of wings in the recent mayfly Cloeon dipterum it was discovered, that the alleged series of immature, subimaginal and imaginal wings of T. guttata and P. fenestrata do not provide clear evidence that would support...

The phylogenetic relationship between Ephemeroptera (mayflies) and Odonata (dragonflies and damselflies) remains hotly debated in the insect evolution community. We sequenced the complete mitochondrial genome of Caenis sp. (Ephemeroptera: Caenidae) to discuss the phylogenetic relationship of Palaeoptera. The mitochondrial genome of Caenis sp. is a circular molecule of 15,254 bp in length containing 37 genes (13 protein-coding genes, 22 tRNAs, and 2 rRNAs), which showed the typical insect mitochondrial gene arrangement. In BI and ML phylogenetic trees using 71 species of 12 orders, our results support the Ephemeroptera as the basal group of winged insects.

Phylogenetic relationships of basal insects remain a matter of discussion. In particular, the relationships among Ephemeroptera, Odonata and Neoptera are the focus of debate. In this study, we used a next-generation sequencing approach to reconstruct new mitochondrial genomes (mitogenomes) from 18 species of basal insects, including six representatives of Ephemeroptera and 11 of Odonata, plus one species belonging to Zygentoma. We then compared the structures of the newly sequenced mitogenomes. A tRNA gene cluster of IMQM was found in three ephemeropteran species, which may serve as a potential synapomorphy for the family Heptageniidae. Combined with published insect mitogenome sequences, we constructed a data matrix with all 37 mitochondrial genes of 85 taxa, which had a sampling concentrating on the palaeopteran lineages. Phylogenetic analyses were performed based on various data coding schemes, using maximum likelihood and Bayesian inferences under different models of sequence evolution. Our results generally recovered Zygentoma as a monophyletic group, which formed a sister group to Pterygota. This confirmed the relatively primitive position of Zygentoma to Ephemeroptera, Odonata and Neoptera. Analyses using site-heterogeneous CAT-GTR model strongly supported the Palaeoptera clade, with the monophyletic Ephemeroptera being sister to the monophyletic Odonata. In addition, a sister group relationship between Palaeoptera and Neoptera was supported by the current mitogenomic data.

Topographic anatomy of ascending (AN) and descending (DN) neurons of the supraesophageal and thoracic ganglia in the nervous system of winged insects (Pterygota), representatives of the infraclasses Palaeoptera (Odonata, Aeschna grandis, dragonfly) and Neoptera (Blattoptera, Periplaneta americana, cockroach), was studied. These insects differ in ecological niches, lifestyles, sets of behavioral complexes, levels of locomotor system development, evolutionary age and systematic position. Cell bodies and processes of ANs and DNs were stained with nickel chloride (NiCl2), and their topography was studied on total preparations of the supraesophageal and thoracic ganglia. Unlike cockroaches, the dragonfly protocerebrum was found to contain DNs sending their processes to ocelli. Dragonfly DN processes exhibit a specific branching pattern in thoracic ganglia, with collaterals coming off both ipsi- and contralaterally. In cockroaches, collaterals of DN processes come off ipsilaterally. The AN cell bodies in dragonfly meso- and metathoracic ganglia lie both ipsi- and contralaterally relative to the ascending process, whereas in cockroaches most of the AN cell bodies in the same ganglia are located contralaterally. Substantial differences in the distrubution of DNs and ANs in insects with different manners of locomotion appear to reflect different degrees of control the supraesophageal ganglion exerts over the activity of segmental centers. This does not seem to be related to the evolutionary age of insects or their systematic position. Probably, different degrees of control over locomotion depend on the way of food acquisition: catching prey in the air in “paleopterous” dragonflies versus maneuverable walking or running over a solid substrate in “neopterous” cockroaches.

We report the discovery of a new Calvertiellidae from the Xiaheyan locality (Namurian, early Late Carboniferous; Tupo Formation; China), namely Xiaheyanella orta gen. et sp. n. Besides representing both the most ancient and the most oriental occurrences for the family, the new species exhibits a derived wing venation pattern, especially if compared to the putative palaeodictyopteran cousins of the family. This discovery shows that, by the early Late Carboniferous, many insect lineages of moderate importance (i.e., considered at the familial level or below) already had a widespread distribution, and that derived conditions already accumulated. This concurs with the view that insects had already experienced a long evolutionary history by that time, remaining to be documented.

The first members of the Palaeozoic insect family Aykhalidae (Megasecoptera) to be described were discovered in Siberia. Two new genera and three species from the Early Pennsylvanian (Namurian) Tupo Formation at Xiaheyan in northern China (Ningxia Hui Autonomous Region) are described on the basis of the patterns of their wing venation. An emended diagnosis of the Aykhalidae is provided based on the larger sample of specimens now available. Sinopalaeopteryx gen. nov. is established with two described species ( S . olivieri sp. nov. and S. splendens sp. nov.). Monotypic Namuroptera gen. nov. is established for N . minuta sp. nov., a species that is markedly smaller in size, has a pointed connection between MA and RP, and very long brace m-cua well aligned with a short rp-m brace compared to Aykhal and Sinopalaeopteryx . All these newly described taxa extend our knowledge of the morphological disparity within the Aykhalidae. Due to the number of shared characters in wing venation, we consider Aykhalidae to be closely related to Sphecopteridae, with a broad distribution across Euramerica, Siberia and North China. In addition, this study documents individual and intraspecific variability in wing venation in the Aykhalidae and Sphecopteridae.

Can you name the five most significant evolutionary changes that made beetles the most successful and diversified of all insects? Hint : check Fig. 1 for the five modifications marked on the evolutionary tree of insect orders. Fig. 1. The most strongly supported clades of the insect orders show dramatic changes in the number of species (estimates based on Gullan and Cranston 2005), suggesting that the changes at the numbered nodes represent major improvements in fitness. Odonata and Ephemeroptera (together known as Palaeoptera) are 3 times as speciose as the more primitive, wingless orders; orthopteroid orders (Pliconeoptera) together are 4 times as speciose as Palaeoptera; hemipteroid orders (here named Clavoptera) are 4 times as speciose as Pliconeoptera; neuropteroid orders (except Coleoptera) are 6 times as speciose as Clavoptera, and Coleoptera alone are almost as speciose as all the other neuropteroid orders put together, and some taxonomists claim that there are more than 10 times as many beetles as other neuropteroids. For morphological and anatomical changes at the numbered nodes, see text. Photograph by Nicholas Aflitto. The first change, of course, is the evolution of wings (node 1 in Fig. 1) that created the paleopterous orders, represented in the modern fauna by Ephemeroptera and Odonata, and the second (node 2) was the ability of Neoptera to fold those wings over the back, preventing them from being damaged when evading predators. The majority of Coleoptera have taken this process one step farther: they can fold their wings in half (node 5) and hide them under the …

The phylogenetic relationships of the winged insect lineages – mayflies (Ephemeroptera), damselflies and dragonflies (Odonata), and all other winged insects (Neoptera) – are still controversial with three hypotheses supported by different datasets: Palaeoptera, Metapterygota and Chiastomyaria. Here, we reanalyze available phylogenomic data with a focus on detecting confounding and alternative signal. In this context, we provide a framework to quantitatively evaluate and assess incongruent molecular phylogenetic signal inherent in phylogenomic datasets. Despite overall support for the Palaeoptera hypothesis, we also found considerable signal for Chiastomyaria, which is not easily detectable by standardized tree inference approaches. Analyses of the accumulation of signal across gene partitions showed that signal accumulates gradually. However, even in case signal only slightly supported one over the other hypothesis, topologies inferred from large datasets switch from statistically strongly supported Palaeoptera to strongly supported Chiastomyaria. From a morphological point of view, Palaeoptera currently appears to be the best-supported hypothesis; however, recent analyses were restricted to head characters. Phylogenetic approaches covering all organ systems including analyses of potential functional or developmental convergence are still pending so that the Palaeoptera problem has to be considered an open question in insect systematics.

Being implied in flight, mimetism, communication, and protection, the insect wings were crucial organs for the mega diversification of this clade. Despite several attempts, the problem of wing evolution remains unresolved because the basal parts of the veins essential for vein identification are hidden in the basivenal sclerites. The homologies between wing characters thus cannot be accurately verified, while they are of primary importance to solve long-standing problems, such as the monophyly of the Palaeoptera, viz. Odonatoptera, Panephemeroptera, and Palaeozoic Palaeodictyopterida mainly known by their wings. Hitherto the tools to homologize venation were suffering several cases of exceptions, rendering them unreliable. Here we reconstruct the odonatopteran venation using fossils and a new 3D imaging tool, resulting congruent with the concept of Riek and Kukalová-Peck, with important novelties, viz. median anterior vein fused to radius and radius posterior nearly as convex as radius anterior (putative synapomorphies of Odonatoptera); subcostal anterior (ScA) fused to costal vein and most basal primary antenodal crossvein being a modified posterior branch of ScA (putative synapomorphies of Palaeoptera). These findings may reveal critical for future analyses of the relationships between fossil and extant Palaeoptera, helping to solve the evolutionary history of the insects as a whole.

The phylogenetic relationships of the winged insect lineages - mayflies (Ephemeroptera), damselflies and dragonflies (Odonata), and all other winged insects (Neoptera) - are still controversial with three hypotheses supported by different datasets: Palaeoptera, Metapterygota and Chiastomyaria. Here, we reanalyze available phylogenomic data with a focus on detecting confounding and alternative signal. In this context, we provide a framework to quantitatively evaluate and assess incongruent molecular phylogenetic signal inherent in phylogenomic datasets. Despite overall support for the Palaeoptera hypothesis, we also found considerable signal for Chiastomyaria, which is not easily detectable by standardized tree inference approaches. Analyses of the accumulation of signal across gene partitions showed that signal accumulates gradually. However, even in case signal only slightly supported one over the other hypothesis, topologies inferred from large datasets switch from statistically strongly supported Palaeoptera to strongly supported Chiastomyaria. From a morphological point of view, Palaeoptera currently appears to be the best-supported hypothesis; however, recent analyses were restricted to head characters. Phylogenetic approaches covering all organ systems including analyses of potential functional or developmental convergence are still pending so that the Palaeoptera problem has to be considered an open question in insect systematics.

The reproductive strategy of insects of inserting eggs into plant tissue (endophytic oviposition) is known from the Late Carboniferous onwards. The earliest known ovipositional scars are large, that is up to 38 mm long, and irregular both in size and in shape, and they are not arranged in a regular pattern. Oviposition patterns resembling those of present-day Odonata are first reported from the Late Palaeozoic. These egg cavities are generally of smaller size and have a regular oval shape. They are usually arranged in longitudinal rows or in a zigzag configuration. The most likely tracemakers were gracile damselfly-like insects such as the Archizygoptera, a group closely related to modern Zygoptera. In this paper, the earliest evidence of endophytic oviposition resembling the ‘Coenagrionid Type’ of Odonatoptera is described. It derives from the Wettin member of the Siebigerode Formation of the Saale-Basin in Central Germany (Upper Carboniferous, Gzhelian) and consists of about 49 elliptical scars with lengths of about 2 mm, probably deposited on a leaf of Cordaites. The arrangement of the scars in short transverse rows, their regular size and elliptical shape suggest that the tracemaker was probably a member of the extinct odonatopteran suborder Archizygoptera. If so, the tracefossil described here would be the earliest evidence for this endophytic oviposition in an ancestral group of modern Zygoptera.

Phylogenetic relationships among the basal orders of winged insects remain unclear, in particular the relationship of the Ephemeroptera (mayflies) and the Odonata (dragonflies and damselflies) with the Neoptera. Insect evolution is thought to have followed rapid divergence in the distant past and phylogenetic reconstruction may therefore be susceptible to problems of taxon sampling, choice of outgroup, marker selection, and tree reconstruction method. Here we newly sequenced three mitochondrial genomes representing the two most diverse families of the Ephemeroptera, one of which is a basal lineage of the order. We then used an additional 90 insect mitochondrial genomes to reconstruct their phylogeny using Bayesian and maximum likelihood approaches. Bayesian analysis supported a basal Odonata hypothesis, with Ephemeroptera as sister group to the remaining insects. This was only supported when using an optimized data matrix from which rogue taxa and terminals affected by long-branch attraction were removed. None of our analyses supported a basal Ephemeroptera hypothesis or Ephemeroptera + Odonata as monophyletic clade sister to other insects (i.e., the Palaeoptera hypothesis). Our newly sequenced mitochondrial genomes ofBaetis rutilocylindratus,Cloeon dipterum, andHabrophlebiodes zijinensishad a complete set of protein coding genes and a conserved orientation except for two inverted tRNAs inH. zijinensis.Increased mayfly sampling, removal of problematic taxa, and a Bayesian phylogenetic framework were needed to infer phylogenetic relationships within the three ancient insect lineages of Odonata, Ephemeroptera, and Neoptera. Pruning of rogue taxa improved the number of supported nodes in all phylogenetic trees. Our results add to previous evidence for the Odonata hypothesis and indicate that the phylogenetic resolution of the basal insects can be resolved with more data and sampling effort.

The holotype is redescribed of the giant pterygote insect Bojophlebia prokopi Kukalova-Peck, 1985 from the Pennsylvanian of the Czech Republic. Multiple errors in the original description are documented and corrected. Bojophlebia prokopi has neither any visible traces of a costal brace nor an anal brace, but it does show triadic branchings of MA, MP, CuA, and even, as rare a plesiomorphy, of CuP. It is therefore rejected as a fossil stem mayfly and attributed as sister group of all other Hydropalaeoptera. The first cladistic analysis of fossil palaeopterous insects, including different palaeodictyopterid groups, is presented. A revised phylogeny of Hydropalaeoptera and the stem line of Ephemeroptera are suggested. Palaeodictyopterida is recognized as sister group of Neoptera; thus Palaeoptera s.l. is rejected as a paraphyletic taxon. Four new higher taxa – Paranotalia, Euhydropalaeoptera, Neopterygota and Litophlebioidea superfam. nov. – are introduced, as well as the new family Lithoneuridae.http://zooba...

In this paper we record a likely instance of ovo-viviparity in a chlorocyphid damselfly from south-western China. If confirmed, this will be the first record of live birthing in the Odonata: indeed in any member of the Palaeoptera. The widespread Asian damselfly Heliocypha perforata (Percheron, 1835) is proposed to be, at least facultatively, viviparous. A female was observed and filmed appearing to deposit pro-larvae directly onto the exposed surface of a half-submerged branch in a small stream in Xishuangbanna Autonomous Dai Prefecture, Yunnan, China. The species is known to deposit eggs in bark crevices close to water but no previous case of actual live births is known.

Palaeodictyopterida is remarkable insect superorder, which formed a significant part of the diversity of upper Palaeozoic insects, but disappeared by the end of the Permian. The main synapomorphy of the superorder is the piercing-sucking mouthparts in the form of a rostrum consisting of five styles. This rostrum was probably used to pierce on plant tissue and for the juice sucking. The same type of mouthparts shared by adults was present also in larvae of Palaeodictyopterida. The external copulatory organs of the superorder members was also showed some morphological interests. The male genitalia consist of a pair of gonostyli and two penial lobes, similarly to the genitalia of recent Ephemeroptera. The female genitalia of Palaeodictyopterida are developed in a form of the ovipositor that can be compared with the endophytic ovipositor of some recent Odonata. This morphological features support placement of Palaeodictyopterida as sister group of Odonatoptera + Panephemeroptera. The main aim of the work was to describe new representatives of the order Megasecoptera, the second largest group of Palaeodictyopterida. Wing venation of Megasecoptera exhibits a reduction of the longitudinal and transverse veins in comparison with the order Palaeodictyoptera. Other body structures were examined mainly in the...

The order in which the 3 groups of winged insects (the Pterygota) diverged from their common ancestor has important implications for understanding the origin of insect flight. But despite this importance, the split between the Odonata (dragonflies and damselflies), Ephemeroptera (mayflies), and Neoptera (the other winged orders) remains very much unresolved. Indeed, previous studies have obtained strong apparent support for each of the 3 possible branching patterns. Here, we present a systematic reinvestigation of the basal pterygote split. Our results suggest that outgroup choice and limited taxon sampling have been major sources of systematic error, even for data sets with a large number of characters (e.g., in phylogenomic data sets). In particular, a data set of 113 taxa provides consistent support for the Palaeoptera hypothesis (the grouping of Odonata with Ephemeroptera), whereas results from data sets with fewer taxa give inconsistent results and are highly sensitive to minor changes in data and methods. We also focus on recent methods that exploit temporal information using fossil calibrations, combined with additional assumptions about the evolutionary process, and so reduce the influence of outgroup choice. These methods are shown to provide more consistent results, for example, supporting Palaeoptera, even for data sets that previously supported other hypotheses. Together, these results have implications for understanding insect origins and for resolving other problematic splits in the tree of life. (Bayesian phylogenetics; BEAST; Chiastomyaria; Metapterygota; Pterygota.)

The relationships of the 3 major clades of winged insects—Ephemeroptera, Odonata, and Neoptera—are still unclear. Many morphologists favor a clade Metapterygota (Odonata+Neoptera), but Chiastomyaria (Ephemeroptera+ Neoptera) or Palaeoptera (Ephemeroptera+Odonata) has also been supported in some older and more recent studies. A possible explanation for the difficulties in resolving these relationships is concerted convergence—the convergent evolution of entire character complexes under the same or similar selective pressures. In this study, we analyze possible instances of this phenomenon in the context of head structures of Ephemeroptera, Odonata, and Neoptera. We apply a recently introduced formal approach to detect the occurrence of concerted convergence. We found that characters of the tentorium and mandibles in particular, but also some other head structures, have apparently not evolved independently, and thus can cause artifacts in tree reconstruction. Our subsequent analyses, which exclude character sets that may be affected by concerted convergence, corroborate the Palaeoptera concept. We show that the analysis of homoplasy and its influence on tree inference can be formally improved with important consequences for the identification of incompatibilities between data sets. Our results suggest that modified weighting (or exclusion of characters) in cases of formally identified correlated cliques of characters may improve morphology-based tree reconstruction. (Character clique; convergent evolution; Chiastomyaria; Ephemeroptera; homoplasy; Metapterygota; morphology; mouthparts; Odonata; phylogeny.)

This is the first reported primary sequence of a bioactive peptide isolated from three Ephemeroptera families. Peptides of the adipokinetic hormone (AKH) family from the corpora cardiaca of nymphs of Afronurus spp. (Family: Heptageniidae), Siphlonurus lacustris (Family: Siphlonuridae) and Ephemera danica (Family: Ephemeridae) were investigated functionally in homologous (hypertrehalosaemic activity demonstrated in E. danica nymphs) and heterologous (active in cockroach and locust) bioassays, and structurally by liquid-chromatography coupled with ion trap electrospray ionisation mass spectrometry. All species investigated synthesise the octapeptide code-named Anaim-AKH (pGlu-Val-Asn-Phe-Ser-Pro-Ser-Trp amide). Confirmation of this peptide being present in corpora cardiaca of E. danica nymphs was obtained via reverse phase-high pressure liquid chromatography. Phylogenetically, the presence of only one AKH peptide may constitute a basal condition; all other lower insect orders, e.g. Odonata, Blattodea, Orthoptera, amongst others, have more than one AKH analogue. We propose that Anaim-AKH is the ancestral peptide which may support the Palaeoptera hypothesis that mayflies (Ephemeroptera) and dragonflies (Odonata) form the Palaeoptera clade, the sister group of Neoptera. The structural data cannot, however, shed any light on the phylogenetic scenarios within Ephemeroptera itself. Finally, this study demonstrates the successful use of larvae as an alternative biological source to study neuropeptides in ephemeral, elusive or difficult to obtain adult insects.

Research over the last two decades has significantly increased our understanding of the evolutionary position of the insects among other arthropods, and the relationships among the insect Orders. Many of these insights have been established through increasingly sophisticated analyses of DNA sequence data from a limited number of genes. Recent results have established the relationships of the Holometabola, but relationships among the hemimetabolous orders have been more difficult to elucidate. As trong con- sensus on the relationships among the Palaeoptera (Ephemeroptera and Odonata) and their relationship to the Neoptera has not emerged with all three possible resolutions supported by different data sets.While polyneopteran relationships generally have resisted significant resolution, it is now clear that termites, Isoptera, are nested within the cockroaches, Blattodea. The newly discovered order Mantophasmatodea is difficult to place with the balance of studies favouring Grylloblattodea as sister-group.While some stu- dies have found the paraneopteran orders (Hemiptera, Thysanoptera, Phthiraptera and Psocoptera) monophyletic, evidence suggests that parasitic lice (Phthiraptera) have evolved from groups within the book and bark lice (Psocoptera), and may represent parallel evolutions of parasitism within two major louse groups. Within Holometabola, it is now clear that Hymenoptera are the sister to the other orders, that, in turn are divided into two clades, the Neuropteroidea (Coleoptera, Neuroptera and relatives) and the Mecopterida (Trichoptera, Lepidoptera, Diptera and their relatives). The enigmatic order Strep- siptera, the twisted wing insects, have now been placed firmly near Coleoptera, rejecting their close rela- tionship to Diptera that was proposed some 15 years ago primarily based on ribosomal DNA data. Phylogenomic-scale analyses are just beginning to be focused on the relationships of the insect orders, and this is where we expect to see resolution of palaeopteran and polyneopteran relationships. Future research will benefit from greater coordination between intra and inter-ordinal analyses. This will max- imise the opportunities for appropriate outgroup choice at the intraordinal level and provide the back- ground knowledge for the interordinal analyses to span the maximum phylogenetic scope within groups.

Most species on Earth are insects and thus, understanding their evolutionary relationships is key to understanding the evolution of life. Insect relationships are increasingly well supported, due largely to technological advances in molecular sequencing and phylogenetic computational analysis. In this postgenomic era, insect systematics will be furthered best by integrative methods aimed at hypothesis corroboration from molecular, morphological, and paleontological evidence. This review of the current consensus of insect relationships provides a foundation for comparative study and offers a framework to evaluate incoming genomic evidence. Notable recent phylogenetic successes include the resolution of Holometabola, including the identification of the enigmatic Strepsiptera as a beetle relative and the early divergence of Hymenoptera; the recognition of hexapods as a crustacean lineage within Pancrustacea; and the elucidation of Dictyoptera orders, with termites placed as social cockroaches. Regions of the tree that require further investigation include the earliest winged insects (Palaeoptera) and Polyneoptera (orthopteroid lineages).

Taphonomic conditions of insects from the Late Carboniferous (Pennsylvanian) Konservat-Lagerstatte Hagen-Vorhalle (western Germany) are remarkably unique but have not been the focus of detailed work thus far. Their particular preservation is conspicuous and furthermore shows significant differences between “Palaeoptera” and Neoptera. The first are almost always completely preserved while the latter invariably lack an abdomen. Furthermore all Neoptera bear tiny bivalve prodissoconchs (~ 0.8–1.2 mm) or few dissoconchs (~ 1.3–1.4 mm) exclusively on the dorsal wing membrane. Taking into account geological, sedimentological, paleontological and paleo-oceanological data a novel taphonomic model is presented here. After a short period of drifting along the water/air contact layer “Palaeoptera” sank directly to the bottom whereas the soft-tissued abdomens of Neoptera began to decay under these oxic conditions. After loosing their abdomen the corpses sank to a pycnocline in a strongly stratified water body where a second period of drifting took place. At this stage the wings were settled by attaching bivalve larvae derived from a river. When the weight of the shells increased the insect/bivalve association broke through the pycnocline and sank to the bottom where they were finally embedded and fossilized.

Mickoleitia longimanus gen. et sp.n. is described from the Lower Cretaceous limestone of the Crato Formation in Brazil. It is attributed to a new family Mickoleitiidae and a new fossil insect order Coxoplectoptera within the palaeopterous Ephemerida, based on the presence of an elongated costal brace. This fossil insect exhibits a very peculiar combination of derived characters like specialized forelegs with strongly elongated, free coxae, single-clawed pretarsus, and distinctly skewed pterothorax as in dragonflies. On the other hand, several plesiomorphies are present that exclude this taxon from modern Ephemeroptera, namely large hind wings with widened anal area and numerous cross veins that separate the elongate costal brace from the costal margin. Fossil larvae described by Willmann as larval Cretereismatidae are herein attributed to Mickoleitiidae fam.n., based on the shared presence of broad hind wing buds with distinctly broadened anal area, wing bud venation similar to the adult holotype, and subchelate forelegs with elongate free coxae. These larvae are also highly autapomorphic in the structure of their abdominal gills and laterally flattened body with vertically oval section that is unique within Ephemerida. On the other hand they possess plesiomorphic lateral wing pads with pronounced articulation like Palaeozoic pterygote larvae, while wing pads in modern insects are always secondarily fused to the tergum. A similar fossil larva from the Jurassic of Transbaikals was earlier described as Mesogenesia petersae and classified within modern mayflies. It is herein attributed to Mickoleitiidae fam.n. Coxoplectoptera are recognized as putative sister group of modern Ephemeroptera based on the shared presence of only 7 pairs of abdominal gills, while Permoplectoptera still have retained 9 pairs of gills. The phylogenetic reclassification of the mayfly stem group by Willmann is critically discussed and modified.

This study determined the first complete mitochondrial genome of a damselfly, Euphaea formosa (Insecta: Odonata: Zygoptera), and reconstructed a phylogeny based on thirteen protein-coding genes of mitochondrial genomes in twenty-five representative hexapods to examine the relationships among the basal Pterygota. The damselfly's mitochondrial genome is a circular molecule of 15,700 bp long, and contains the entire set of thirty-seven genes typically found in insects. The gene arrangement, nucleotide composition, and codon usage pattern of the mitochondrial genome are similar across the three odonate species, suggesting a conserved genome evolution within the Odonata. The presence of the intergenic spacer s5 likely represents a synapomorphy for the dragonflies (Anisoptera). Maximum parsimony, maximum likelihood, and Bayesian analyses of both nucleotide and amino acid sequences cannot support the three existing phylogenetic hypotheses of the basal Pterygota (Palaeoptera, Metapterygota, and Chiastomyaria). In contrast, the phylogenetic results indicate an alternative hypothesis of a strongly supported basal Odonata and a sister relationship of the Ephemeroptera and Plecoptera. The unexpected sister Ephemeroptera + Plecoptera clade, which contradicts with the widely accepted hypothesis of a monophyletic Neoptera, requires further analyses with additional mitochondrial genome sampling at the base of the Neoptera.

A new syntonopterid, Anglolithoneura magnifica gen. et sp. n., is described from a siderite concretion (nodule) from the Late Carboniferous (Langsettian) of Lancashire County (UK). The new genus is diagnosed on hind wing venation and compared with other syntonopterid genera. The new species is the first syntonopterid formally described from the Late Carboniferous of Europe. The systematic positions of other potential Syntonopteroidea (Miracopteron mirabile, Bojophlebia prokopi, and specimens described in 1985 by J. Kukalova-Peck from Obora in the Czech Republic) are reconsidered. Wing venation synapomorphies are proposed for the Syntonopteroidea (sensu novo), and for a potential clade ((Ephemeroptera+Syntonopteroidea)+Odonatoptera) separated from the Palaeodictyopterida. The close relations of the new species with Lithoneura lameerei Carpenter, 1938 from Mazon Creek (Illinois, USA) provide additional support for a Euramerican connection during the Late Carboniferous.

Pterygota are traditionally divided in two lineages, the "Palaeoptera" and Neoptera. Despite several efforts neither morphology nor molecular systematics have resolved the phylogeny of the pterygote insects. Too few markers have yet been identified for adequately tracking mesozoic-aged divergences. We tested the Elongation factor-1alpha for its phylogenetic value in pterygote insect systematics. This highly conserved nuclear protein-coding gene has previously been reported to be useful in other groups for phylogenetic analyses at the intraordinal level as well as at the interordinal level. The analyses suggest that EF-1alpha DNA sequences as well as intron positions provide informative markers for pterygote phylogenetics.

In the search for the sister group of modern Ephemerida, we used the evolutionary groundplan method to identify synapomorphies in wing articulation. The evolutionary approach is necessary because post-groundplan wing adaptations have obscured the phylogenetically informative higher-level synapomorphies in modern Ephemerida, Odonata and Neoptera. Protowing-level sclerites are recognisable fragments of the first limb-derived pleuron, arranged in eight rows above the pathways delivering blood to the eight principal wing veins. Each row includes three sclerites (proxalare, axalare and fulcalare) which articulate with the basivenale (wing blood sinus). Over the course of the pterygote evolutionary history, many row-sclerites have assembled into clusters, plates, or processes, the composition of which can be most clearly recognised by comparison with ancestral Paleozoic fossils. The extant orders Ephemerida and Odonata (Palaeoptera: Hydropalaeoptera) share a derived anterior articular plate (AAP) composed of fo...

One of the most fascinating Bauplan transitions in the animal kingdom was the invention of insect wings, a change that also contributed to the success and enormous diversity of this animal group. However, the origin of insect flight and the relationships of basal winged insect orders are still controversial. Three hypotheses have been proposed to explain the phylogeny of winged insects: 1) the traditional Palaeoptera hypothesis (Ephemeroptera + Odonata, Neoptera), 2) the Metapterygota hypothesis (Ephemeroptera, Odonata + Neoptera), and 3) the Chiastomyaria hypothesis (Odonata, Ephemeroptera + Neoptera). Neither phylogenetic analyses of single genes nor even multiple marker systems (e.g., molecular markers + morphological characters) have yet been able to conclusively resolve basal pterygote divergences. A possible explanation for the lack of resolution is that the divergences took place in the mid-Devonian within a short period of time and attempts to solve this problem have been confounded by the major challenge of finding molecular markers to accurately track these short ancient internodes. Although phylogenomic data are available for Neoptera and some wingless (apterygote) orders, they are lacking for the crucial Odonata and Ephemeroptera orders. We adopt a multigene approach including data from two new expressed sequence tag projects-from the orders Ephemeroptera (Baetis sp.) and Odonata (Ischnura elegans)-to evaluate the potential of phylogenomic analyses in clarifying this unresolved issue. We analyzed two data sets that differed in represented taxa, genes, and overall sequence lengths: maxspe (15 taxa, 125 genes, and 31,643 amino acid positions) and maxgen (8 taxa, 150 genes, and 42,541 amino acid positions). Maximum likelihood and Bayesian inference analyses both place the Odonata at the base of the winged insects. Furthermore, statistical hypotheses testing rejected both the Palaeoptera and the Metapterygota hypotheses. The comprehensive molecular data set developed here provides conclusive support for odonates as the most basal winged insect order (Chiastomyaria hypothesis). Data quality assessment indicates that proteins involved in cellular processes and signaling harbor the most informative phylogenetic signal.

ummary 1. The evidence for Hennig‘S (1969) hierarchial classification of the higher hexapodan taxa (here termed “orders”) is reviewed and additional data are considered. 2. The monophyly of the Hexapoda and the sister group relationship between Entognatha and Insecta (Archaeognatha + Zygentoma + Pterygota) are accepted. MANTON'S theory of an independent origin of Diplura, Protura, Collemboia, Thysanura (s. lat.) and Pterygota is found to be based on an unwarranted importance attached to autapomorphies and on inadequate considerations of those ancestral stages considered by Manton to be “functionally impossible”. 3. The monophyly of Hennig'S taxon Dicondylia (Zygentoma + Pterygota) is accepted and substantiated by further evidence. 4. A taxon constituted by the recent palaeopteran orders, Ephemeroptera and Odonata, is not accepted as monophyletic, the latter order being considered the sister group of the Neoptera. 5. The phylogenetic interrelationships of the lower neopteran orders (Plecoptera + Pauro-metabola sensu HENNIG) are considered entirely unclarified. HENNIG'S classification as well as the theories on supraordinal relationships by, e. g., BLACKITH and BLACKITH (1968), GILES (1963), RICHARDS and DAVIES (1957), Ross (1965), RAHLE (1970), SHAROV (1968/71) and WILLE (1960) are shown to be very weakly founded, but construction of an alternative classification is not attempted. The monophyletic nature of the order Blattopteroidea (Man-todea + Blattariae + Isoptera) is considered firmly established. 6. The ground plan of the Phasmatodea is inadequately known. The current primary division of the order is questioned, and the Californian genus Timema is suggested to be the primitive sister-group of all other Phasmatodea together. 7. The monophyly of the taxon “Eumetabola” (Paraneoptera + Holometabola) is substantiated only by its possession of a “jugal bar” (HAMILTON 1972). SHAROV'S (1966) account of the phylogenetic significance of embryonic growth patterns in the major pterygote division is discarded. 8.HENNIG'S theory of the paraneopteran nature of the Zoraptera is preferred to theories of blattopteroid affinities of this order. Assumedly specific zorapteran-isopteran similarities are invalidated by those characters in the Zoraptera (corpotentorium, female subgenital plate) which show that this order could at most have been the sister-group of the Blatto-pteroidea as a whole. 9. The monophyly of the entities Psocodea (Psocoptera + Phthiraptera) and Condylognatha (Hemiptera + Thysanoptera) is accepted. It is likely that the Psocoptera is paraphyletic in terms of Phthiraptera. HENNIG'S subdivisions of the Hemiptera: Heteropteroidea (including Coleorrhyncha), Auchenorrhyncha and Sternorrhyncha are accepted. 10. MICKOLEIT'S (1973) findings concerning the ovipositor-structures provide the most weighty evidence for the monophyly of the Neuropteroidea (Megaloptera + Raphidioptera + Neuroptera) and for the relationship of this group to the Coleoptera. Following KINZEL-BACH (1971), the Strepsiptera is tentatively placed as the sister-group of the Coleoptera. 11. HENNIG'S suggestion of a sister-group relationship between the Hymenoptera and the Mecopteroidea probably provides the best working hypothesis of the position of the former group. 12. The Mecopteroidea and its two sub-groups Amphiesmenoptera (Trichoptera + Lepido-ptera) and Antliophora (Mecoptera + Siphonaptera + Diptera) are considered mono-phyletic entities. The arguments, mentioned by HENNIG, against the inclusion of the Siphonaptera in the Mecopteroidea are discarded, and evidence is provided for a sister-group relationship between this order and Mecoptera (including Neomecoptera). The Zeugloptera are true Lepidoptera. Zusammenfassung Die Stammesgeschichte der „Ordnungen” der Hexapoden. Eine kritische Beurteilung des heutigen Wissens 1. Die Grundlagen der hierarchischen Klassifikation der hoheren Taxa der Hexapoden (hier „Ordnungen” genannt) von HENNIG (1969) werden uberpruft und durch zusatzliche Daten beurteilt. 2. Die Monophylie der Hexapoda und die Schwestergruppen-Beziehungen zwischen Ento-gnatha und Insecta (Archaeognatha + Zygentoma + Pterygota) werden ubernommen. Es wird gezeigt, das die Theorie von MANTON uber einen eigenen Ursprung der Diplura, Protura, Collembola, Thysanura (s. lat.) und Pterygota begrundet ist auf einer nicht ge-rechtfertigten Betonung von Autapomorphien und auf unangemessenen Erwagungen iiber jene ancestralen Stufen, die MANTON als „funktionell unmoglich” bezeichnet. 3. Die Monophylie von HENNIGS Taxon Dicondylia (Zygentoma + Pterygota) wird ubernommen und durch weitere Befunde untermauert. 4. Nicht anerkannt als monophyletisch wird ein Taxon, welches aus den rezenten palaeopteren Ordnungen Ephemeroptera und Odonata gebildet wurde. Die Odonata werden als die Schwestergruppe der Neoptera erachtet. 5. Die stammesgeschichtlichen Beziehungen der Ordnungen der niederen Neoptera (Pleco-ptera + Paurometabola sensu HENNIG) werden als vollig ungeklart bezeichnet. Sowohl die Klassifikation durch HENNIG als auch die Theorien von Uberordnungsbeziehungen, vertre-ten durch BLACKITH und BLACKITH (1968), GILES (1963), RICHARDS und DAVIES (1957), Ross (1965), RAHLE (1970), SHAROV (1968/71) und WILLE (1960) sind sehr schwach begriindet; eine alternative Klassifikation wird aber nicht versucht. Die Monophylie der Ordnung Blattopteroidae (Mantodea + Blattariae + Isoptera) wird als wohl begrundet angesehen. 6. Der Grundplan der Phasmatodea ist ungenugend bekannt. Die derzeitige Gliederung der Ordnung wird in Frage gestellt und die kalifornische Gattung Timema als die primitive Schwestergruppen aller anderen Phasmatodea erachtet. 7. Die Monophylie des Taxons „Eumetabola” (Paraneoptera + Holometabola) grundet sich nur auf den Besitz eines „jugal bar” (HAMILTON 1972). SHAROVS (1966) Hinweis auf die phylogenetische Bedeutung des embryonalen Wachstumsmusters wird verworfen. 8. HENNIGS Theorie von der paraneopteren Natur der Zoraptera wird gegenuber den Theorien einer blattopteroiden Verwandtschaft dieser Ordnung der Vorzug gegeben. Hervor-gehobene besondere Ahnlichkeiten zwischen Zoraptera und Isoptera werden bedeutungslos, weil andere Eigenarten der Zoraptera (Corpotentorium, weibliche Subgenitalplatte) darauf hinweisen, das diese Ordnung hochstens als die Schwestergruppe der Blattopteroidea in ihrer Gesamtheit gelten kann. 9. Die Monophylie der Einheiten Psocodea (Pocoptera + Phthiraptera) und Condylognatha (Hemiptera + Thysanoptera) wird ubernommen. Es ist wahrscheinlidi, das die Psocoptera paraphyletisdi mit Rucksicht auf die Phthiraptera sind. HENNIGS Untergliederung der Hemiptera in Heteropteroidea (einsdilieslich Coleorrhyncha), Auchenorrhyndia und Sternor-rhyncha wird anerkannt. 10. MICKOLEITS (1973) Eeststellungen an den Ovipositor-Strukturen stellen die widitigsten Grundlagen fur eine Monophylie der Neuropteroidea (Megaloptera + Raphidioptera + Neuroptera) dar sowie fur Beziehungen dieser Gruppe zu den Coleoptera. Gemas KINZEL-BACH (1971) werden die Strepsiptera zOgernd als Schwestergruppe der Coleoptera be-zeichnet. 11. HENNIGS Annahme einer Schwestergruppenbeziehung zwischen Hymenoptera und den Mecopteroidea ist wahrscheinlidi die beste Arbeitshypothese Uber die Stellung der erst-genannten Gruppe. 12. Die Mecopteroidea und ihre zwei Untergruppen Amphiesmenoptera (Tridioptera + Lepido-ptera) und Antliophora (Mecoptera + Siphonaptera+Diptera) werden als monophyletisch eraditet. Die von HENNIG genannten Argumente gegen die Einbeziehung der Siphonaptera in die Mecopteroidea werden nicht ubernommen; es werden Hinweise darauf gemacht, dafi zwischen dieser Gruppe und Mecoptera (einschlieslich Neomecoptera) Sdiwestergruppen-beziehungen bestehen. Die Zeugloptera sind echte Lepidoptera.

The first complete mitochondrial genome of a mayfly, Parafronurus youi (Arthropoda: Insecta: Pterygota: Ephemeroptera: Heptageniidae), was sequenced using a long PCR-based approach. The genome is a circular molecule of 15,481 bp in length, and encodes the set of 38 genes. Among them, 37 genes are found in other conservative insect mitochondrial genomes, and the 38(th) unique gene is trnM-like (trnM2). The duplication-random loss model can be used to explain one of the translocations at least. The A+T content of the control region is 57%, the lowest proportion detected so far in Hexapoda. Based on the nucleotide dataset and the corresponding amino acid dataset of 12 protein-coding genes, Bayesian inference and maximum likelihood analyses yielded stable support for the relationship of the three basal clades of winged insects as Ephemeroptera+(Odonata+Neoptera).

The classification of insect order Odonata is traced from Linnaeus’ Systema Naturae, through 19th and 20th century morphology-based taxonomies, to molecular phylogenies published before November, 2007. Past and present nomenclatural difficulties are reviewed and the current situation in regard to rival taxonomies is outlined. Ordinal classifications based on morphological data continue to suffer from intractable uncertainty concerning wing vein homologies between Odonata and other Pterygota, but molecular analyses may soon show where the phylogenetic tree of Odonata should be rooted. The natural classification will become much clearer once this has been achieved.

The ability to fly is the decisive factor for the evolutionary success of winged insects (Pterygota). Despite this, very little is known about the ground-pattern and evolution of the functionally very important wing base. Here we use the Ephemeroptera, usually regarded as the most ancient flying insects, as a model for the analysis of the flight musculature and the sclerites of the wing base. Morphology and anatomy of the pterothorax of 13 species of Ephemeroptera and five species of Plecoptera were examined and a detailed description of Habroleptoides confusa (Ephemeroptera: Leptophlebiidae) is given. A new homology of the wing base sclerites in Ephemeroptera is proposed. The wing base of Ephemeroptera possesses three axillary sclerites that are homologous to the first axillary, the second axillary and the third axillary of Neoptera. For example, the third axillary possesses the axillary-pleural muscle that mostly is considered as a characteristic feature of the Neoptera. Many of the muscles and sclerites of the flight system of the Ephemeroptera and Neoptera can be readily homologised. In fact, there are indications that a foldable wing base may be a ground plan feature of pterygote insects and that the non-foldable wing base of the Ephemeroptera is a derived state.

The order Zoraptera (angel insects) is one of the least known insect groups, containing only 32 extant species. The phylogenetic position of Zoraptera is poorly understood, but it is generally thought to be closely related to either Paraneoptera (hemipteroid orders: booklice, lice, thrips, and bugs), Dictyoptera (blattoid orders: cockroaches, termites, and mantis), or Embioptera (web spinners). We inferred the phylogenetic position of Zoraptera by analyzing nuclear 18S rDNA sequences, which we aligned according to a secondary structure model. Maximum likelihood and Bayesian analyses both supported a close relationship between Zoraptera and Dictyoptera with relatively high posterior probability. The 18S sequences of Zoraptera exhibited several unusual properties: (1) a dramatically increased substitution rate, which resulted in very long branches; (2) long insertions at helix E23; and (3) modifications of secondary structures at helices 12 and 18.

Polyneoptera is a name sometimes applied to an assemblage of 11 insect orders comprising the lower neopterous or “orthopteroid” insects. These orders include familiar insects such as Orthoptera (grasshoppers), Blattodea (roaches), Isoptera (termites) (Mantodea) praying mantises, Dermaptera (earwigs), Phasmatodea (stick insects), Plecoptera (stoneflies), as well as the more obscure, Embiidina (web-spinners), Zoraptera (angel insects) and Grylloblattodea (ice-crawlers). Many of these insect orders exhibit a high degree of morphological specialization, a condition that has led to multiple phylogenetic hypotheses and little consensus among investigators. We present a phylogenetic analysis of the polyneopteran orders representing a broad range of their phylogenetic diversity and including the recently described Mantophasmatodea. These analyses are based on complete 18S rDNA, 28S rDNA, Histone 3 DNA sequences, and a previously published morphology matrix coded at the ordinal level. Extensive analyses utilizing different alignment methodologies and parameter values across a majority of possible ranges were employed to test for sensitivity of the results to ribosomal alignment and to explore patterns across the theoretical alignment landscape. Multiple methodologies support the paraphyly of Polyneoptera, the monophyly of Dictyoptera, Orthopteroidea (sensu Kukalova-Peck; i.e. Orthoptera + Phasmatodea + Embiidina), and a group composed of Plecoptera + Dermaptera + Zoraptera. Sister taxon relationships between Embiidina + Phasmatodea in a group called “Eukinolabia”, and Dermaptera + Zoraptera (“Haplocercata”) are also supported by multiple analyses. This analysis also supports a sister taxon relationship between the newly described Mantophasmatodea, which are endemic to arid portions of southern Africa, and Grylloblattodea, a small order of cryophilic insects confined to the north-western Americas and north-eastern Asia, in a group termed “Xenonomia”. This placement, coupled with the morphological disparity of the two groups, validates the ordinal status of Mantophasmatodea. © The Willi Hennig Society 2005.

The nuclear small subunit rRNA (18S) has played a dominant role in the estimation of relationships among insect orders from molecular data. In previous studies, 18S sequences have been aligned by unadjusted automated approaches (computer alignments that are not manually readjusted), most recently with direct optimization (simultaneous alignment and tree building using a program called "POY"). Parsimony has been the principal optimality criterion. Given the problems associated with the alignment of rRNA, and the recent availability of the doublet model for the analysis of covarying sites using Bayesian MCMC analysis, a different approach is called for in the analysis of these data. In this paper, nucleotide sequence data from the 18S small subunit rRNA gene of insects are aligned manually with reference to secondary structure, and analyzed under Bayesian phylogenetic methods with both GTR+I+G and doublet models in MrBayes. A credible phylogeny of Insecta is recovered that is independent of the morphological data and (unlike many other analyses of 18S in insects) not contradictory to traditional ideas of insect ordinal relationships based on morphology. Hexapoda, including Collembola, are monophyletic. Paraneoptera are the sister taxon to a monophyletic Holometabola but weakly supported. Ephemeroptera are supported as the sister taxon of Neoptera, and this result is interpreted with respect to the evolution of direct sperm transfer and the evolution of flight. Many other relationships are well-supported but several taxa remain problematic, e.g., there is virtually no support for relationships among orthopteroid orders. A website is made available that provides aligned 18S data in formats that include structural symbols and Nexus formats.

The Order Diaphanopterodea Handlirsch, 1919, is a small Paleozoic order of winged insects. For a long time, most of its species have been assigned to the order Megasecoptera. The position of the wings held backward along the abdomen at rest (Handlirsch, 1919, p. 575) is currently used to discriminate Diaphanopterodea from Megasecoptera (Carpenter, 1992). Although these Palaeoptera are frequently preserved with wings connected to the body, the wings resting position is not really suitable for ordinal diagnosis: isolated wings cannot be assigned, and taphonomic bias can render interpretations of wing disposal difficult. Here we redescribe Diaphanoptera munieri Brongniart, 1893, type-species of the Diaphanopteridae, and Diaphanoptera vetusta Brongniart, 1893. New diagnostic venation characters are established, some of which were already used for several others representatives of the order (Kukalova-Peck, 1974; Kukalova-Peck and Sinichenkova, 1992). The implications in the composition of the family and its relationships within the order are discussed. In the following part we use the venation nomenclature of Kukalova-Peck (1991). Abbreviations: ScA, anterior Subcosta; ScP, posterior Subcosta; RA, anterior Radius; RP, posterior Radius; MA, anterior Media; MP, posterior Media; CuA, anterior Cubitus; CuP, posterior Cubitus; AA, anterior Anal. ### Order Diaphanopterodea Handlirsch, 1906 Family Diaphanopteridae Handlirsch, 1906 Diaphanopteridae Handlirsch, 1906, p. 313; Carpenter, 1963, p. 241. Diaphanopteritidae Handlirsch, 1919, p. 575; Rohdendorf, 1962, p. 69. #### Type genus Diaphanoptera Brongniart, 1893. #### New diagnosis ScA long parallel to anterior margin, distally vanishing in a pigmented (sclerotized?) apical area; area between anterior margin and ScA pigmented (sclerotized?); apex slightly pointed and slightly rejected posteriorly; ScP ending on RA just distal of midway of wing; few cross-veins between ScA and ScP, irregularly spaced, with one cross-vein just opposite end of ScP on RA; ScP and R basally posteriorly bowed; all cross-veins between RA and RP close to …

Insect wings are very specific and unique structures in animal kingdom. Wing morphology is a result of long-standing complicated evolutionary process and until recently the way how the wings have evolved is not completely clarified. The flight ability is one of the most important event in insect history because it allows them to exploit new habitats, escape from predators or find the sexual partner. Here we present the newly discovered material consisting of Palaeodictyoptera immature wings from the Upper Carboniferous (Westphalian A) of Poland. This order became extinct in the end of Permian, however during the Late Paleozoic was remarkably diversified. Until recently, number of adult palaeodictyopterans have been described, however the immature stages are relatively unknown due to lack of suitable fossils. Immature wings present in this thesis have undoubtedly palaeodictyopterous affinities with atribution within superfamilies Breyeroidea and Homoiopteroidea. However, their familial assignment into Breyeriidae (morphotype A) and Homiopteridae (morphotype B) based on fore wing venation characters is not definite because of wing venation limits in early ontogenetic stages. The aim of the present work is a complex description of 14 new palaeodictyopteriids immature wings, and to point out certain important...

The first and last occurrences of hexapod families in the fossil record are compiled from publications up to end-2009. The major features of these data are compared with those of previous datasets (1993 and 1994). About a third of families (>400) are new to the fossil record since 1994, over half of the earlier, existing families have experienced changes in their known stratigraphic range and only about ten percent have unchanged ranges. Despite these significant additions to knowledge, the broad pattern of described richness through time remains similar, with described richness increasing steadily through geological history and a shift in dominant taxa, from Palaeoptera and Polyneoptera to Paraneoptera and Holometabola, after the Palaeozoic. However, after detrending, described richness is not well correlated with the earlier datasets, indicating significant changes in shorter-term patterns. There is reduced Palaeozoic richness, peaking at a different time, and a less pronounced Permian decline. A pronounced Triassic peak and decline is shown, and the plateau from the mid Early Cretaceous to the end of the period remains, albeit at substantially higher richness compared to earlier datasets. Origination and extinction rates are broadly similar to before, with a broad decline in both through time but episodic peaks, including end-Permian turnover. Origination more consistently exceeds extinction compared to previous datasets and exceptions are mainly in the Palaeozoic. These changes suggest that some inferences about causal mechanisms in insect macroevolution are likely to differ as well.

Monophyly of the pterygote insects is generally accepted, but the relationships among the three basal branches (Odonata, Ephemeroptera and Neoptera) remain controversial. The traditional view, to separate the pterygote insects in Palaeoptera (Odonata + Ephemeroptera) and Neoptera, based on the ability or inability to fold the wings over the abdomen, has been questioned. Various authors have used different sets of morphological characters in support of all three possible arrangements of the basal pterygote branches. We sequenced 18S and 28S rDNA from 18 species of Odonata, 8 species of Ephemeroptera, 2 species of Neoptera, and 1 species of Archaeognatha in our study. The new sequences, in combination with sequences from GenBank, have been used in a parsimony jackknife analysis resulting in strong support for a monophyletic Palaeoptera. Morphological evidence and the phylogenetic implications for understanding the origin of insect flight are discussed.