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Abstract: We investigated the variability in amino acid sequences between mitochondrial cytochrome c oxidase subunit II (COII) domains, as well as that of gene sequences encoding the corresponding domains. According to the secondary structure, COII consisted of five domains of N- and C-terminal regions posited in the intermembrane space, two transmembrane helices (TM1 and TM2) in the lipid bilayer, and a matrix-embedded loop (ML) that intervened between the two helices. Our analysis, using dictyopteran insects as model species, revealed that amino acid and nucleotide substitution rates were heterogeneous between the COII domains. The amino acid substitution rates were higher in the TM1 (0.380±0.123) and ML domains (0.416±0.184), whereas they were relatively lower in the N-terminal (0.204±0.123) and TM2 domains (0.184±0.088). As expected by the variability in the amino acid substitution rates, the average nucleotide substitution rates were also relatively higher in the TM1 (0.312±0.081) and ML domains (0.302±0.093), whereas the lowest substitution rate was observed in the N domain (0.191±0.073). These results indicate that the heterogeneous substitution rates between COII domains, as well as genes encoding the domains, might be closely related to the inner membrane environment where each region of the amino acid sequence is laid. [Copyright &y& Elsevier]

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. A strong consensus 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 studies 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 Strepsiptera, the twisted wing insects, have now been placed firmly near Coleoptera, rejecting their close relationship 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 maximise the opportunities for appropriate outgroup choice at the intraordinal level and provide the background knowledge for the interordinal analyses to span the maximum phylogenetic scope within groups. [ABSTRACT FROM AUTHOR]

The mitochondrial genomes are one of the most information-rich markers in phylogenetics. The relationships within superorder Dictyoptera have been debated in the literature. However, the closely related termites (Isoptera) are retained as unranked taxon within the order Blattaria (cockroaches). In this work, we sequenced the complete mitogenomes of two cockroaches, reconstructed the molecular phylogeny and attempted to infer the phylogenetic position of termites in Blattaria more reliably. The complete mtDNA nucleotide sequences of the peridomestic American cockroach ( Periplaneta americana L.) and the domestic German cockroach ( Blattella germanica L.) are 15,025 and 15,584 bp in size, respectively. The genome shares the gene order and orientation with previously known Blattaria mitogenomes. Most tRNAs could be folded into the typical cloverleaf secondary structure, but the tRNA-Ser (AGN) of P. americana appears to be missing the dihydrouridine arm. Using nucleotide and amino acid sequences as phylogenetic markers, we proposed that termites should be treated as a superfamily (Termitoidea) of cockroaches. We suggested that Polyphagoidea was the sister group of Termitoidea in Blattaria and supported that the suborder Caelifera is more closely related to the Phasmatodea than to the suborder Ensifera of Orthoptera. [ABSTRACT FROM AUTHOR]

We have designed and utilized degenerate primers in the phylogenetic analysis of [FeFe] hydrogenase gene diversity in the gut ecosystems of roaches and lower termites. H is an important free intermediate in the breakdown of wood by termite gut microbial communities, reaching concentrations in some species exceeding those measured for any other biological system. The primers designed target with specificity the largest group of enzymatic H domain proteins previously identified in a termite gut metagenome. 'Family 3' hydrogenase sequences were amplified from the guts of lower termites, Incisitermes minor, Zootermopsis nevadensis, and Reticulitermes hesperus, and two roaches, Cryptocercus punctulatus and Periplaneta americana. Subsequent analyses revealed that all termite and Cryptocercus sequences were phylogenetically distinct from non-termite-associated hydrogenases available from public databases. The abundance of unique sequence operational taxonomic units (as many as 21 from each species) underscores the previously demonstrated physiological importance of H to the gut ecosystems of these wood-feeding insects. The diversity of sequences observed might be reflective of multiple niches that the enzymes have been evolved to accommodate. Sequences cloned from Cryptocercus and the lower termite samples, all of which are wood feeding insects, clustered closely with one another in phylogenetic analyses to the exclusion of alleles from P. americana, an omnivorous cockroach, also cloned during this study. We present primers targeting a family of termite gut [FeFe] hydrogenases and provide results that are consistent with a pivotal role for hydrogen in the termite gut ecosystem and point toward unique evolutionary adaptations to the gut ecosystem. [ABSTRACT FROM AUTHOR]

Abstract: External and internal head structures of the mantodean Hymenopus coronatus are examined and described in detail. The results are elaborately compared with the literature. Strong crests on the anterior tentorial arms that articulate with the subantennal suture, a parietal suture and glossae and paraglossae with anteriorly bent tips are proposed as new potential apomorphies for Mantodea while a head capsule being wider than long, enlarged compound eyes, the presence of a frontal shield or scutellum, lateral lobes in the anterior tentorial arms, the presence of a transverse and an interantennal suture and the reduction of the mentum are confirmed as apomorphies, As potential apomorphies for Dictyoptera the reduction of Musculus tentoriobuccalis lateralis (M. 49) is newly presented and a “perforate” tentorium, lacinial incisivi that are located in a galeal pouch and the presence of a postmola are confirmed. The present study shows the value of cephalic morphology for phylogenetic analysis but also points out that further studies including evolutionary key taxa are essential for resolving the evolutionary adaptations among dictyopterans. [Copyright &y& Elsevier]

The article presents a report on the first roach recovered from the Kota Formation assigned to a genus of Mesoblattinidae, a family well known from the Middle Jurassic through the Late Cretaceous including amber inclusions. The Archimesoblatta Vrsansky is an elongated mesoblattinid roaches with subparallel forewing margins, veins strongly curved proximally and with secondary branches present apically. The new species Archimesoblatta has relatively more simplified venation with only 15 branches to R and relative small size reaching only 9.5mm when complete. It expects richer abundance of material and more thorough characterization of the roach Archimesoblatta with further exploration in India.

We addressed the phylogeny of cockroaches using DNA sequence data from a broad taxon sample of Dictyoptera and other non-endopterygotan insect orders. We paid special attention to several taxa in which relationships are controversial, or where no molecular evidence has been used previously: Nocticolidae, a family of small, often cave-dwelling cockroaches, has been suggested to be the sister group of the predaceous Mantodea or of the cockroach family Polyphagidae; Lamproblatta, traditionally placed in Blattidae, has recently been given family status and placed as sister to Polyphagidae; and Saltoblattella montistabularis Bohn, Picker, Klass & Colville, a jumping cockroach, which has not yet been included in any phylogenetic studies. We used mitochondrial ( COI + COII and 16S) and nuclear ( 18S and 28S) genes, and analysed the data using Bayesian inference (BI) and maximum likelihood (ML). Nocticolidae was recovered as sister to Polyphagidae. Lamproblatta was recovered as sister to Blattidae, consistent with the traditional placement (not based on phylogenetic analysis). However, because of the limited support for this relationship and conflict with earlier morphology-based phylogenetic hypotheses, we retain Lamproblattidae. S. montistabularis was consistently placed as sister to Ectobius sylvestris Poda (Blaberoidea: Ectobinae), indicating that the saltatorial hindlegs of this genus are a relatively recent adaptation. Isoptera was placed within Blattodea as sister to Cryptocercidae. Nocticolidae + Polyphagidae was sister to Isoptera + Cryptocercidae, and Blaberoidea was sister to the remaining Blattodea. [ABSTRACT FROM AUTHOR]

Wood-feeding cockroaches in the genus Crytocercus live in biparental family groups in the interior of rotten logs and are considered socially monogamous. They typically produce a single brood of altricial offspring, with parental care then lasting until the death of adults 2 or 3 years later. Field and laboratory evidence suggests that copulation occurs repeatedly in C. punctulatus, with sexual activity occurring during non-fertile periods. We carried out a long-term field study to explore the significance of repeated copulation in C. punctulatus. The presence of a male positively affected the onset of female reproduction, but neither the male's physical presence nor his ability to mate influenced the number or early development of nymphs. Sperm are viable in the spermathecae for at least 3 years. We conclude that it is unlikely that male-derived material benefits have driven the evolution of repeated copulation in C. punctulatus. Accumulating evidence suggests that prior to oviposition, repeated copulation may be rooted in sperm competition, but after the eggs are laid it may secure the continued paternal contribution of the male social partner. [ABSTRACT FROM AUTHOR]

In subsocial xylophagous cockroaches it is thought that parental feeding is important for the survival and growth of the altricial offspring, but the details of parental feeding in these groups are poorly known. We observed stomodeal (oral) trophallaxis between parents and the 2nd or 3rd instars of the wood-feeding cockroach Salganea esakii Roth, and here report basic features of trophallaxis in young families. Both the female and male parents fed young nymphs with stomodeal food, and there was no difference in the frequency of the behavior between parental sexes. Up to three nymphs could be fed simultaneously during a single trophallactic event. Adults occasionally rejected contact with nymphs by blocking them with their forelegs. Nymphs utilized trophallactic food from parents more frequently than feeding independently on wood pieces or fecal pellets. Trophallaxis between sibling nymphs was never observed. These results suggest that the 2nd and 3rd instar nymphs rely on the stomodeal substances provided by their parents, and that provisioning is an essential component of subsocial behavior in biparental wood-feeding cockroaches. [ABSTRACT FROM AUTHOR]

For convenience, we treat all "polyneopteran" orders together. Five orders of hemimetabolous "Polyneoptera" include species alien to Europe, namely Blattodea, Isoptera, Orthoptera, Phasmatodea and Dermaptera. A total of 37 species alien to Europe have been recorded. These belong to 14 different families. Most of these species show a detritivorous feeding regime (22 spp.), whereas 12 species are phytophagous and two are predators. Th e majority of species were first observed between 1900 and 1975. Unlike other arthropod groups, the mean number of polyneopteran species newly recorded per year showed no acceleration since 1975. Th e alien "Polyneoptera" mostly originated from Central/ South America and Asia (10 species each, 27.0%), followed by Africa (7, 18.9%). Germany hosts the largest number of alien Polyneoptera (15 spp.), followed by Denmark (14), Spain (11) and France (10). All but one alien species represent unintentional introductions. More than 75% of the species are associated with artificial habitats (houses, buildings and greenhouses) and cultivated areas. Blattodea and Isoptera have huge economic and/ or medical importance. Th e cost of treatments and sanitary measures against termites and cockroaches, in particular, is significant in Europe. [ABSTRACT FROM AUTHOR]

The article discusses a study that investigated the computer reconstructions of Archimylacris eggintoni, a Carboniferous stem-group dictyopteran. Scanning of a siderite-hosted specimen using high-resolution X-ray microtomography was carried out. It was observed that the mandibles of Archimylacris eggintoni are closely comparable to the mouthparts of crown-group cockroaches. It concludes that the resolution of appendage morphology can give insights into the life of Carboniferous organisms.

We present the complete mitochondrial DNA sequence of Eupolyphaga sinensis. This closed circular molecule is 15553 bp long and consists of 37 genes that encode for 13 inner membrane proteins, 2 ribosomal RNAs and 22 transfer RNAs. The genome shares the gene order and orientation with previously known Blattaria mitochondrial genomes. All tRNAs could be folded into the typical cloverleaf secondary structure, but the tRNASer (AGN) appears to be missing the DHU arm. The A + T-rich region is 857 bp long and longer than other cockroaches. Based on the concatenated amino acid sequences of all protein coding genes of E. sinensis in conjunction with those 23 other arthropod sequences, we reconstruct the phylogenetic tree. Phylogenetic analyses shows that Blataria (including Isoptera) and the Mantodea are sister groups. Furthermore the relationship of the three basal clades of winged insects are different from the three previous hypotheses ((Ephemeroptera + Odonata) +Neoptera, Ephemeroptera + (Odonata + Neoptera), Odonata + (Ephemeroptera +Neoptera)). The Ephemeroptera ( Parafronurus youi) clusters with the Plecoptera ( Pteronarcys princes). [ABSTRACT FROM AUTHOR]

The article presents a study which characterized the species of Protomagalhaensia parasitizing Phoetalia pallida or Paillid cockroach. Gamonts of Protomagalhaensia species are differentiated from those of P. cerastes in terms of size and shape. Oocysts of Protomagalhaensia granulosae and Protomagalhaensia serpentia have apical corner spines or knobs, which are absent in the oocysts of Protomagalhaensia wolfi, Protomagalhaensia blaberae and P. cerastes.

The skeletal morphology of the transition area between the tibia and the tarsus is described for Dictyoptera, with a focus on Blaberus craniifer (Blattodea) and Sphodromantis viridis (Mantodea), but with 8 mantodean and 39 blattodean species (including 3 termite species) examined altogether. We emphasise the occurrence in most dictyopterans of a small sclerite located on the anteroventral side of the leg, between the margins of the tibia and the tarsus facing each other, the intertibiotarsal sclerite (abbreviated as itts: tibio-tarsal band/ligament sensu D. Neff and co-workers). The itts region is shown on SEM micrographs for a representative subset of our taxon sample. Comparison with selected outgroup species and data from the literature indicates that sclerite itts is autapomorphic for Dictyoptera and further confirms the monophyly of the group. Details of sclerite itts yield characters for phylogenetic work in Dictyoptera, such as a dorsal extension of the sclerite limited to a subset of our mantodean sample. In Cryptocercidae cockroaches and in termites sclerite itts is vestigial or absent, respectively. This could be interpreted as supporting termites to be the sister group of all remaining Dictyoptera, followed by Cryptocercidae. In the light of recent phylogenetic work, however, this rather appears to be a reductive apomorphy, which then further supports Cryptocercidae to be the sister group of termites. Functional aspects of the tibiotarsal articulation in Dictyoptera are also addressed, with a focus on the roles of and interdependence among the dorsal tibiotarsal articulation, the itts sclerite, and the tendons originating from the proximal rim of the tarsus (bearing the tarsal muscles); on this issue a functional model is presented. Most importantly, the effects of the tarsal muscles are being modulated with the status of itts (expanded or bent underneath). [ABSTRACT FROM AUTHOR]

Sociality in insects may negatively impact on species richness. We tested whether termites have experienced shifts in diversification rates through time. Supertree methods were used to synthesize family-level relationships within termites, cockroaches and mantids. A deep positive shift in diversification rate is found within termites, but not in the cockroaches from which they evolved. The shift is responsible for most of their extant species richness suggesting that eusociality is not necessarily detrimental to species richness, and may sometimes have a positive effect. Mechanistic studies of speciation and extinction in eusocial insects are advocated. [ABSTRACT FROM AUTHOR]

We compiled a preliminary list of insects for the Orinoco Basin based on the Entomological Collection of the Alexander von Humboldt Institute (IAvH). Our review expanded the information for four orders of insects (Coleoptera, Dictyoptera, Hemiptera and Hymenoptera). We found a total of 168 species, belonging to 156 genera, 59 tribes, 39 subfamilies and 15 families. We documented 84 new records for the Colombian Orinoco Basin and five new records for Colombia. [ABSTRACT FROM AUTHOR]

The article discusses the revision of the tribe Toxoderini, which is composed of large mantises having pointed eyes and foliaceous expansions on the mid and hind femora thriving in South-Eastern Asia. The author states that they are considered under the Toxoderini classification and often classified as a subfamily within Mantidae. He also mentions that some of the genera, which are distinguished by their pronotum and cerci structure, are mentioned including Protoxodera, Toxodera and Stenotoxodera.

Background: Neuropeptide ligands have to fit exactly into their respective receptors and thus the evolution of the coding regions of their genes is constrained and may be strongly conserved. As such, they may be suitable for the reconstruction of phylogenetic relationships within higher taxa. CAPA peptides of major lineages of cockroaches (Blaberidae, Blattellidae, Blattidae, Polyphagidae, Cryptocercidae) and of the termite Mastotermes darwiniensis were chosen to test the above hypothesis. The phylogenetic relationships within various groups of the taxon Dictyoptera (praying mantids, termites and cockroaches) are still highly disputed. Results: Tandem mass spectrometry of neuropeptides from perisympathetic organs was used to obtain sequence data of CAPA peptides from single specimens; the data were analysed by Maximum Parsimony and Bayesian Interference. The resulting cladograms, taking 61 species into account, show a topology which is in general agreement with recent molecular and morphological phylogenetic analyses, including the recent phylogenetic arrangement placing termites within the cockroaches. When sequence data sets from other neuropeptides, viz. adipokinetic hormones and sulfakinins, were included, the general topology of the cladogram did not change but bootstrap values increased considerably. Conclusion: This study represents the first comprehensive survey of neuropeptides of insects for solely phylogenetic purposes and concludes that sequences of short neuropeptides are suitable to complement molecular biological and morphological data for the reconstruction of phylogenetic relationships. [ABSTRACT FROM AUTHOR]

Insects deciding whether to approach and join a group of conspecifics may utilize olfactory and auditory signals, or cues, from that group as indicators of its size or the suitability of its shelter. Here we show (1) that German cockroaches, Blattella germanica L. (Dictyoptera: Blattellidae), in groups wing-fan; (2) that the incidence of wing-fanning (WF) increases proportionately to group size; and (3) that gravid females utilize auditory cues associated with WF behaviour when they decide whether or not to enter a shelter. In binary choice arena bioassays, proportionately more gravid females avoided shelters associated with play-back of high-incidence male- or female-produced WF sound, indicating a high-density group of conspecifics, but sought shelters associated with play-back of low-incidence WF sound, indicating a low-density group of conspecifics. These auditory cues seem to convey information on group size or density, avoid sensory fatigue in enclosed environments, and allow sonotactic orientation to the group's location. [ABSTRACT FROM AUTHOR]

Dictyoptera, comprising Blattaria, Isoptera, and Mantodea, are diverse in appearance and life history, and are strongly supported as monophyletic. We downloaded COII, 16S, 18S, and 28S sequences of 39 dictyopteran species from GenBank. Ribosomal RNA sequences were aligned manually with reference to secondary structure. We included morphological data (maximum of 175 characters) for 12 of these taxa and for an additional 15 dictyopteran taxa (for which we had only morphological data). We had two datasets, a 59-taxon dataset with five outgroup taxa, from Phasmatodea (2 taxa), Mantophasmatodea (1 taxon), Embioptera (1 taxon), and Grylloblattodea (1 taxon), and a 62-taxon dataset with three additional outgroup taxa from Plecoptera (1 taxon), Dermaptera (1 taxon) and Orthoptera (1 taxon). We analysed the combined molecular−morphological dataset using the doublet and MK models in MrBayes, and using a parsimony heuristic search inpaup. Within the monophyletic Mantodea, Mantoida is recovered as sister to the rest of Mantodea, followed by Chaeteessa; the monophyly of most of the more derived families as defined currently is not supported. We recovered novel phylogenetic hypotheses about the taxa within Blattodea (following Hennig, containing Isoptera). Unique to our study, one Bayesian analysis places Polyphagoidea as sister to all other Dictyoptera; other analyses and/or the addition of certain orthopteran sequences, however, place Polyphagoidea more deeply within Dictyoptera. Isoptera falls within the cockroaches, sister to the genus Cryptocercus. Separate parsimony analyses of independent gene fragments suggest that gene selection is an important factor in tree reconstruction. When we varied the ingroup taxa and/or outgroup taxa, the internal dictyopteran relationships differed in the position of several taxa of interest, including Cryptocercus, Polyphaga, Periplaneta and Supella. This provides further evidence that the choice of both outgroup and ingroup taxa greatly affects tree topology. [ABSTRACT FROM AUTHOR]

This paper reviews the current state of knowledge about Blattaria for Colombia. Generalities on the suborder are presented and the species present in Colombia are catalogued. This study was made based on the literature and analysis of the various Colombian collections. The species listing obtained is made up of four families with 15 subfamilies, 62 genera and 133 species that account for 3.1% of the 4,330 species recognized worldwide. Moreover, an altitudinal range is given as well as distribution data for Colombia's biogeographical regions and departments. Some notes are made on the distribution for each region and on collection methods. [ABSTRACT FROM AUTHOR]

The article presents a study regarding Neotropical mantids such as Insecta, Mantodea and Dictyoptera. It mentions that Mantodea is an group of insects who are also considered as predators like the praying mantis. A checklist of Mantodea including taxon, habitat or location and distribution is likewise included.

Abstract: The first comprehensive combined molecular and morphological phylogenetic analysis of the major groups of termites is presented. This was based on the analysis of three genes (cytochrome oxidase II, 12S and 28S) and worker characters for approximately 250 species of termites. Parsimony analysis of the aligned dataset showed that the monophyly of Hodotermitidae, Kalotermitidae and Termitidae were well supported, while Termopsidae and Rhinotermitidae were both paraphyletic on the estimated cladogram. Within Termitidae, the most diverse and ecologically most important family, the monophyly of Macrotermitinae, Foraminitermitinae, Apicotermitinae, Syntermitinae and Nasutitermitinae were all broadly supported, but Termitinae was paraphyletic. The pantropical genera Termes, Amitermes and Nasutitermes were all paraphyletic on the estimated cladogram, with at least 17 genera nested within Nasutitermes, given the presently accepted generic limits. Key biological features were mapped onto the cladogram. It was not possible to reconstruct the evolution of true workers unambiguously, as it was as parsimonious to assume a basal evolution of true workers and subsequent evolution of pseudergates, as to assume a basal condition of pseudergates and subsequent evolution of true workers. However, true workers were only found in species with either separate- or intermediate-type nests, so that the mapping of nest habit and worker type onto the cladogram were perfectly correlated. Feeding group evolution, however, showed a much more complex pattern, particularly within the Termitidae, where it proved impossible to estimate unambiguously the ancestral state within the family (which is associated with the loss of worker gut flagellates). However, one biologically plausible optimization implies an initial evolution from wood-feeding to fungus-growing, proposed as the ancestral condition within the Termitidae, followed by the very early evolution of soil-feeding and subsequent re-evolution of wood-feeding in numerous lineages. [Copyright &y& Elsevier]

Cockroaches (Dictyoptera, Mylacridina) from the Chunya locality (Upper Carboniferous of the Central Siberian Plateau) are considered. New representatives of the family Phyloblattidae Schneider, 1983 ( Phyloblatta majuscula sp. nov., P. chunyensis sp. nov., Hesperoblatta vishniakovae sp. nov., and H. secunda sp. nov.) are described. [ABSTRACT FROM AUTHOR]

New taxa of the suborder Blattina (order Dictyoptera), possibly belonging to the family Corydiidae ( Erucoblatta semicaeca gen. et sp. nov., Miocene; Proholocompsa gen. nov., Eocene; and Holocompsa nigra sp. nov. and H. abbreviata sp. nov., Miocene) and belonging to the family Ectobiidae ( Plectoptera electrina sp. nov., Miocene; Agrabtoblatta symmetrica gen. et sp. nov. and ?Symploce rete sp. nov., Pleistocene) are described. The taxonomic position of the enigmatic genus Raphidiomimula Grimaldi et Ross from the Upper Cretaceous is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Adults of warm- and cold-acclimated tropical cockroaches, Nauphoeta cinerea were exposed to low temperatures of 0 or 5 °C for various time intervals (hours to days). Development of chilling-injury (defects in crawling and uncoordinated movements) and mortality during the exposure were assessed and correlated with the changes in concentrations of metal ions (Na+, K+ and Mg2+) in the haemolymph and coxal muscle tissue. Warm-acclimated insects entered chill-coma at both low temperatures. In their haemolymph, the [Na+] and [Mg2+] linearly decreased and [K+] increased with the increasing time of exposure. The rate of concentration changes was higher at 0 than at 5 °C. The concentration changes resulted in gradually dissipating equilibrium potentials across the muscle cell membranes. For instance, E K decreased from −49.8 to −20.7 mV during 7 days at 5 °C. Such a disturbance of ion homeostasis was paralleled by the gradual development of chilling-injury and mortality. Most of the cockroaches showed chilling-injury when the molar ratio of [Na+]/[K+] in their haemolymph decreased from an initial of 4.4 to 2.1–2.5. In contrast, the cold-acclimated cockroaches did not enter chill-coma. They maintained constant concentrations of ions in their haemolymph, constant equilibrium potentials across muscle cell membranes and the development of chilling-injury was significantly suppressed at 5 °C for 7 days. [Copyright &y& Elsevier]

Virgin mantis females,Hierodula patellifera(Serville) (Dictyoptera: Mantidae), exhibit a characteristic calling posture. When holding the body below a branch or leaf, the female curls the abdomen ventrally, flexing it away from the wings and exposing its dorsal surface. The curling is accompanied by pumping movements. The average age at which females start adopting this calling posture is 14 days after adult moult, and it is related to their nutritional stage. Once initiated, females exhibit the posture everyday until they mate. After mating, the behaviour is completely suppressed. Males are attracted by virgin females adopting the calling posture but are not attracted to mated females. The characteristics of the posture and the responsive behaviour of the males indicate that this female calling involves the release of sex pheromones. [ABSTRACT FROM AUTHOR]

We review literature on extant detritivores, including cockroaches and termites, and conclude that coprophagy was the key behavior leading to the evolution of hindgut fermentation systems in the stem group of Dictyoptera. Coprophagy exploits concentrated microbial consortia on cellulose based substrates. These microbes are potential mutualists and food, but they also initiate degradation of cellulose, detoxify allelochemicals and soften the substrate, a phenomenon known as the "external rumen". We suggest that the evolution of a sophisticated hindgut fauna is a process of internalizing this self-assembled microbial community, accompanied by changes in host-microbe interdependence, the source of microbial inoculum for neonates, and host social behavior. Proctodeal trophallaxis evolved from pre-existing intraspecific coprophagous behavior when termite ancestors became subsocial, because the physiology of encystment in oxymonad and hypermastigid flagellates precludes their transfer via cysts in adult feces. The behavior was reinforced by the benefits of using the trophic stages of flagellates as food. The association of these flagellates with the dictyopteran lineage is an ancient one, and may have originated as part of the external rumen in the Carboniferous coal swamps. [ABSTRACT FROM AUTHOR]

AbstractKlass, K.-D., Thorne, B. L. and Lenz, M. 2000. The male postabdomen of Stolotermes inopinus: a termite with unusually well-developed external genitalia (Dictyoptera: Isoptera: Stolotermitinae). — Acta Zoologica (Stockholm) 81: 121–130 Stolotermes inopinus has large external male genitalia (phallic lobe), which contrast with the small genital papillae or lack of external genitalia of other Isoptera. As in the genital papilla of Mastotermes darwiniensis, a ventral sclerite pair is present, the gonopore is located ventroterminally on the phallic lobe, and the genital area is entirely symmetrical – suggesting that this may be the groundplan condition of Isoptera. The relations of the phallic lobe to surrounding components like the subgenital plate, paraprocts, and certain muscles and nerves indicate that the lobe of S. inopinus is homologous with the phallomeres of other Dictyoptera. The bilateral symmetry and simple structure, however, are in strong contrast to the asymmetry and high complexity found in male genitalia of Blattaria and Mantodea. The postabdominal nervous system of S. inopinus resembles that of the cockroach Periplaneta americana. Indications are given that the Stolotermitinae are related to the Kalotermitidae, Rhinotermitidae, and Termitidae rather than to the Termopsinae. [ABSTRACT FROM AUTHOR]

Alienopteridae are among the most perplexing fossil insects and once conspicuous members of Cretaceous Dictyoptera (now including cockroaches, termites and mantises). However, the precise nature of their life history, evolution, and phylogenetic affinities remained controversial and open to debate. Here we report new alienopterid nymphs from mid-Cretaceous Kachin amber (approximately 99 Ma) and define three nymphal morphotypes, along with proposed interpretations of their life style. We also re-evaluate the systematic position of Alienopteridae, and of the recently erected order Aethiocarenodea. Geometric morphometric analyses suggest that morphotype I nymphs exhibit distinct morphological specializations that were most likely associated with ant mimicry, like immature stages of some modern crown mantises. Remarkably, mimetic association between these nymphs and stem-group ants provides the earliest record of ant mimicry (myrmecomorphy), which is contemporary with the earliest ants and their eusociality. We discuss different interpretations of the life history of alienopterid adults, especially wasp mimicry, and conclude that Teyia was likely a wasp mimic. The nymphs (morphotype I) and adults of Teyia resemble different models, which provides the first fossil record of transformational mimicry, implying that this behaviour had already evolved by the mid-Cretaceous. In addition, one alienopterid nymph laden with pollen clumps provides evidence for gymnosperm pollination and a previously unknown gymnosperm-insect association. This suggests that extinct dictyopterans might have been among the earliest pollinators, with a hitherto undervalued role in pollination ecology. Our phylogenetic analysis provides evidence that Alienopteridae and Umenocoleidae together constitute a monophyletic group (Alienoptera), which is placed as sister taxon of Mantodea. Alienoptera including Umenocoleidae were supported as a separate lineage, and mainly characterized by sclerotized shell-like tegmina and unique leg structures, their main diversification probably occurred before the J/K boundary, and we suggest a common evolutionary origin during the Late Jurassic. [ABSTRACT FROM AUTHOR]

Background: Cockroaches are usually typical omnivorous detritivores and their cephalic morphology is considered to be ancestral in various aspects. Thus, several studies addressed the morphology and function of the blattodean head, and the cockroach usually serves as a model for standard mouthparts in text books. However, so far only two of the three major lineages of Blattodea have been studied and no detailed information for the head of any Corydioidea was available. The present study closes this gap by providing a detailed morphological description of the head of Ergaula capucina , studying some important functional parameters of the mandible and discussing it in a phylogenetic framework., Methods: The cephalic morphology of Ergaula studied in detail using a broad set of different techniques including digital microscopy, µ-computed tomography, and 3-dimensional reconstructions. Concerning the functional morphology of the mandible, we compared the volume and effective cross sections of the eight compartments of the primary mandibular adductor muscle for Ergaula , Blattella germanica , and Salganea rossi and measured the mechanical advantage, i.e. , the force transmission ratio for all teeth of the mandible of Ergaula ., Results: The head capsule of Ergaula is characterized by a strong sexual dimorphism and typical orthopteran mouthparts. It resembles the head capsule of other roaches in several respects and confirms oesotendons, the reduction of the mesal occelus, and bipartite M. verticopharyngealis and M. hypopharyngosalivaris as blattodean apomorphies. But it also shows some unique adaptations. It is the first described cockroach that lacks the dorsal tentorial arms which has various consequences for the cephalic musculature. On the maxillary lacinia, Ergaula is the first described blattodean to show strong and blunt setae instead of a lacinula, which might be homologues to the dentisetae of dragonflies and mayflies. Like other corydiid roaches that inhabit xeric areas, Ergaula has an atmospheric water-vapor absorption mechanism that includes a gland and a ductus on the epipharnyx and bladders on the hypopharynx. The mandibular adductor is in cockroaches asymmetric, a pattern not found in termites, mantids, or other closely related insects., Competing Interests: The authors declare that they have no competing interests., (© 2022 Wipfler et al.)