Cuticular nitrogen economy during development in the cockroach Cryptocercus punctulatus and the termite Neotermes jouteli.

The role of nitrogen during insect development and reproduction is key in the success of a species, and is of primary importance in wood feeding taxa. Based on comparison of xylophagous, one-piece termites to the termite sister group, subsocial wood-feeding cockroaches in the genus Cryptocercus, it has been proposed that the evolution of termite eusociality involved a fundamental shift in nitrogen allocation strategies. Cryptocercus exhibits a nitrogen storage economy, with individuals gradually increasing in size and cuticular density over a years-long developmental period.

Extra-pair paternity in the wood-feeding cockroach Cryptocercus punctulatus Scudder: Social but not genetic monogamy.

Subsocial Cryptocercus cockroaches are the sister group to termites and considered to be socially monogamous. Because genetic monogamy is a suggested requirement for evolution of cooperative breeding/eusociality, particularly in hymenopterans, clarification of the mating biology of Cryptocercus would help illuminate evolutionary trends in eusocial insects. To investigate possible extra-pair paternity in C.

Wasp Size and Prey Load in (Hymenoptera, Crabronidae): Implications for Biosurveillance of Pest Buprestidae.

The relationship between predator and prey size was studied in the buprestid hunting wasp Say in eight widely distributed nesting aggregations in North Carolina, USA. Initial work indicated a significant linear relationship between wasp head width and wasp wet weight; thus, head width was used to estimate wasp body mass in subsequent studies. Prey loads of hunting females was studied by measuring the head width of the wasp, then identifying and weighing the prey item brought back to the nest.

A Crucial Caste Regulation Gene Detected by Comparing Termites and Sister Group Cockroaches.

Sterile castes are a defining criterion of eusociality; investigating their evolutionary origins can critically advance theory. In termites, the soldier caste is regarded as the first acquired permanently sterile caste. Previous studies showed that juvenile hormone (JH) is the primary factor inducing soldier differentiation, and treatment of workers with artificial JH can generate presoldier differentiation.

Parallel and Gradual Genome Erosion in the Blattabacterium Endosymbionts of Mastotermes darwiniensis and Cryptocercus Wood Roaches.

Almost all examined cockroaches harbor an obligate intracellular endosymbiont, Blattabacterium cuenoti. On the basis of genome content, Blattabacterium has been inferred to recycle nitrogen wastes and provide amino acids and cofactors for its hosts. Most Blattabacterium strains sequenced to date harbor a genome of ∼630 kbp, with the exception of the termite Mastotermes darwiniensis (∼590 kbp) and Cryptocercus punctulatus (∼614 kbp), a representative of the sister group of termites.

What Kills the Hindgut Flagellates of Lower Termites during the Host Molting Cycle?

Subsocial wood feeding cockroaches in the genus , the sister group of termites, retain their symbiotic gut flagellates during the host molting cycle, but in lower termites, closely related flagellates die prior to host ecdysis. Although the prevalent view is that termite flagellates die because of conditions of starvation and desiccation in the gut during the host molting cycle, the work of L.R.

Distribution of Karyotypes of the Cryptocercus punctulatus Species Complex (Blattodea: Cryptocercidae) in Great Smoky Mountains National Park.

During the period between 1999 and 2006, wood-feeding cockroaches in the Cryptocercus punctulatus Scudder species complex were collected throughout Great Smoky Mountains National Park, USA. The chromosome numbers of insects from 59 sites were determined, and phylogenetic analyses were performed based on mitochondrial COII and nuclear ITS2 DNA. The distribution of the three male karyotypes found in the park (2n = 37, 39, and 45) is mapped and discussed in relation to recent disturbances and glacial history.

Genome Evolution and Nitrogen Fixation in Bacterial Ectosymbionts of a Protist Inhabiting Wood-Feeding Cockroaches.

Unlabelled: By combining genomics and isotope imaging analysis using high-resolution secondary ion mass spectrometry (NanoSIMS), we examined the function and evolution of Bacteroidales ectosymbionts of the protist Barbulanympha from the hindguts of the wood-eating cockroach Cryptocercus punctulatus In particular, we investigated the structure of ectosymbiont genomes, which, in contrast to those of endosymbionts, has been little studied to date, and tested the hypothesis that these ectosymbionts fix nitrogen. Unlike with most obligate endosymbionts, genome reduction has not played a major role in the evolution of the Barbulanympha ectosymbionts. Instead, interaction with the external environment has remained important for this symbiont as genes for synthesis of transporters, outer membrane proteins, lipopolysaccharides, and lipoproteins have been retained.

The role of host phylogeny varies in shaping microbial diversity in the hindguts of lower termites.

The hindguts of lower termites and Cryptocercus cockroaches are home to a distinct community of archaea, bacteria, and protists (primarily parabasalids and some oxymonads). Within a host species, the composition of these hindgut communities appears relatively stable, but the evolutionary and ecological factors structuring community composition and stability are poorly understood, as are differential impacts of these factors on protists, bacteria, and archaea. We analyzed the microbial composition of parabasalids and bacteria in the hindguts of Cryptocercus punctulatus and 23 species spanning 4 families of lower termites by pyrosequencing variable regions of the small-subunit rRNA gene.

Antennal cropping during colony foundation in termites.

The literature on pairing and mating behavior in termites indicates that a number of distal antennal segments in dealates of both sexes are often removed during colony foundation, with terms such as amputation, mutilation and cannibalism typically employed to report the phenomenon. Here we propose the use of the phrase 'antennal cropping' to describe the behavior, and assess naturally occurring levels of its occurrence by comparing the number of antennal segments in museum specimens of alates and dealates in 16 species of Australian termites (four families), supplemented by analyzing published data on Coptotermes gestroi. Dealates had significantly fewer antennal segments than alates in 14 of the 16 termite species, with both exceptions belonging to the family Termitidae.

Biogeography and Phylogeny of Wood-feeding Cockroaches in the Genus Cryptocercus.

Subsocial, xylophagous cockroaches of the genus Cryptocercus exhibit a disjunct distribution, with representatives in mature montane forests of North America, China, Korea and the Russian Far East. All described species are wingless and dependent on rotting wood for food and shelter at all stages of their life cycle; consequently, their distribution is tied to that of forests and strongly influenced by palaeogeographical events. Asian and American lineages form distinct monophyletic groups, comprised of populations with complex geographic substructuring.

Altricial development in subsocial cockroach ancestors: foundation for the evolution of phenotypic plasticity in termites.

Basal termites possess two developmental features that eusocial Hymenoptera lack: the majority of colony members are juveniles whose somatic and reproductive development is temporarily or permanently suspended, and individual development is characterized by extreme phenotypic plasticity. An examination of the literature indicates that the basis for these unique ontogenetic characters is not the prolongation of a pronymphal stage into postembryonic development, as recently suggested. Like other hemimetabolous insects, termites have three embryonic cuticles, and the pronymphal (EC3) cuticle is shed during or shortly after hatch.

Phylogenetic analysis of cellulolytic enzyme genes from representative lineages of termites and a related cockroach.

The relationship between xylophagous termites and the protists resident in their hindguts is a textbook example of symbiosis. The essential steps of lignocellulose degradation handled by these protists allow the host termites to thrive on a wood diet. There has never been a comprehensive analysis of lignocellulose degradation by protists, however, as it has proven difficult to establish these symbionts in pure culture.

Altricial development in subsocial wood-feeding cockroaches.

Species in the wood-feeding genus Salganea within the cockroach subfamily Panesthiinae (Blaberidae) typically live in biparental families; their first instars suffer high mortality when removed from adults, and in at least one species, adults are known to feed neonates on oral liquids. In the closely related gregarious wood-feeding genus Panesthia , no parental interaction with offspring is known. We compared the external morphology of first instars of these two genera and found that eye development and cuticular pigmentation at hatching are correlated with social structure.

Inheritance and diversification of symbiotic trichonymphid flagellates from a common ancestor of termites and the cockroach Cryptocercus.

Cryptocercus cockroaches and lower termites harbour obligate, diverse and unique symbiotic cellulolytic flagellates in their hindgut that are considered critical in the development of social behaviour in their hosts. However, there has been controversy concerning the origin of these symbiotic flagellates. Here, molecular sequences encoding small subunit rRNA and glyceraldehyde-3-phosphate dehydrogenase were identified in the symbiotic flagellates of the order Trichonymphida (phylum Parabasalia) in the gut of Cryptocercus punctulatus and compared phylogenetically to the corresponding species in termites.

The Cryptocercus punctulatus species complex (Dictyoptera: Cryptocercidae) in the eastern United States: comparison of cuticular hydrocarbons, chromosome number, and DNA sequences.

The goal of the current study was to determine if cuticular hydrocarbons could be used to empirically delimit taxa within the Cryptocercus punctulatus species complex in the eastern United States. Cockroaches were collected from rotting logs in 22 locations across four states. Hydrocarbon phenotypes and two mitochondrial (16S and COII) genes and one nuclear (ITS2) gene were independently analyzed to determine their relationship with chromosome number.

Wood-feeding cockroaches as models for termite evolution (Insecta: Dictyoptera): Cryptocercus vs. Parasphaeria boleiriana.

Isoptera are highly specialized cockroaches and are one of the few eusocial insect lineages. Cryptocercus cockroaches have appeared to many as ideal models for inference on the early evolution of termites, due to their possible phylogenetic relationship and several shared key attributes in life history. Recently, Pellens, Grandcolas, and colleagues have proposed the blaberid cockroach Parasphaeria boleiriana to be an alternative model for the early evolution in termites.

The fine structure of colleterial glands in two cockroaches and three termites, including a detailed study of Cryptocercus punctulatus (Blattaria, Cryptocercidae) and Mastotermes darwiniensis (Isoptera, Mastotermitidae).

The colleterial glands of insects are organs associated with the female genital apparatus. In cockroaches, these glands produce secretions that cover two parallel rows of eggs during oviposition, and in oviparous species, these secretions become the tanned, sculpted, rigid outer casing of the ootheca. The goal of this study was to compare the gross anatomy of the colleterial glands and the ultrastructure of their component tubules in the phylogenetically significant genera Cryptocercus (Blattaria) and Mastotermes (Isoptera).

Harmonia axyridis (Coleoptera: Coccinellidae) in buildings: relationship between body height and crevice size allowing entry.

Although the introduced lady beetle Harmonia axyridis (Pallas) (Coleoptera: Coc-cinellidae) is an important predator of aphids in a variety of crop systems during the growing season, it is often a pest in fall and winter when it enters buildings seeking overwintering sites. One of the primary recommendations for managing this annual influx is to prevent beetle entry by caulking or otherwise filling potential entry points in buildings. The goal of this study was to determine how small a gap the beetles are able to enter in choice and no-choice studies by experimentally exploiting their behavioral tendency to seek dark shelters at cool temperatures.

Infection of Harmonia axyridis (Coleoptera: Coccinellidae) by Hesperomyces virescens (Ascomycetes: Laboulbeniales): role of mating status and aggregation behavior.

The ectoparasitic fungus Hesperomyces virescens was studied on Harmonia axyridis in North Carolina, in the southeastern United States. A primary goal was to investigate transmission of the disease by examining the correlation between the pattern of fungal infection and seasonal change in host behavior. Beetles were collected as they arrived at their winter quarters at two sites; in one site they were also subsampled at mid- and late winter.

Molecular phylogeny of Cryptocercus wood-roaches based on mitochondrial COII and 16S sequences, and chromosome numbers in Palearctic representatives.

Woodroaches of the genus Cryptocercus are subsocial and xylophagous cockroaches, distributed in North America and Asia. Studies on male chromosome number in Nearctic species have shown that diploid numbers vary from 2n=37 to 2n=47; numbers from Palearctic species were heretofore unknown. Two hypotheses have been proposed to explain the varying number of chromosomes among Nearctic species: the serial reduction hypothesis, and the parallel scenario.

Identification and characterization of ectosymbionts of distinct lineages in Bacteroidales attached to flagellated protists in the gut of termites and a wood-feeding cockroach.

Bacterial attachments to nearly the entire surface of flagellated protists in the guts of termites and the wood-feeding cockroach Cryptocercus are often observed. Based on the polymerase chain reaction-amplified 16S rRNA gene sequences, we investigated the phylogenetic relationships of the rod-shaped, attached bacteria (ectosymbionts) of several protist species from five host taxa and confirmed their identity by fluorescence in situ hybridizations. These ectosymbionts are affiliated with the order Bacteroidales but formed three distinct lineages, each of which may represent novel bacterial genera.

Evidence for cocladogenesis between diverse dictyopteran lineages and their intracellular endosymbionts.

Bacteria of the genus Blattabacterium are intracellular symbionts that reside in specialized cells of cockroaches and the termite Mastotermes darwiniensis. They appear to be obligate mutualists, and are transmitted vertically in the eggs. Such characteristics are expected to lead to equivalent phylogenies for host and symbiont, and we tested this hypothesis using recently accumulated data on relationships among termites and cockroaches and their Blattabacterium spp.