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The aim of this work was to assess the virulence of strain M379 of the fungus, Metarhizium anisopliae (Metchnikoff) Sorokin (Hypocreales: Clavicipitaceae) after different passages through a suitable host and at different concentrations for the control of both acaricide-susceptible and resistant strains of the tick, Rhipicephalus (formerly Boophilus) microplus Canestrini (Ixodida:Ixodidae) in vitro. The highest value of LC50 for the susceptible strain corresponded to zero passage with 7.68 × 107 conidia/ml followed by the fourth passage with 2.68 × 107, which reduced 2.87-fold the lethal concentration. When comparing LC50 values of the fourth vs. the seventh passage (2.59 × 105 conidia/ml), the lethal concentration was reduced 103.47-fold by the seventh passage. In addition, in the resistant strain the LC50 highest value corresponded to zero passage with 4.95 × 107 conidia/ml followed by the fourth passage with 7.86 × 106, which reduced 6.30-fold the lethal concentration. When comparing LC50 values of the fourth vs. the seventh passage (1.04 × 105 conidia/ml) in the resistant strain, the lethal concentration was reduced 75.58-fold by the seventh passage. These results suggest that the number of passages on M. anisopliae through a suitable host increased its virulence on both R. microplus strains. When comparing LC50 of the zero passage through a suitable host of both acaricide-susceptible and resistant strains, the highest LC50 values corresponded to the susceptible strain with 7.68 × 107 conidia/ml followed by the resistant one with 4.95 × 107, showing that on the resistant strain the lethal concentration is reduced by 1.55-fold. When comparing the fourth passage, the highest values of LC50 corresponded to the susceptible strain with 2.68 x 107 conidia/ml followed by the resistant one with 7.86 × 106 conidia/ml, showing for the resistant strain a 3.41-fold reduced lethal concentration. Moreover, when comparing the seventh passages, the highest values of LC50 corresponded to the susceptible strain with 2.59 × 105 followed by the resistant with 1.04 × 105 conidia/ml, revealing for the resistant strain a 2.49-fold reduced lethal concentration. These results suggest that the resistant strain needs a lower concentration of conidia than the susceptible strain. In this case, the acaricide-resistant strain is more susceptible to M. anisopliae of zero- and seven-passage strains.

The extent to which environmental heterogeneity can account for tree species coexistence in diverse ecosystems, such as tropical rainforests, is hotly debated, although the importance of spatial variability in contributing to species co-existence is well recognized. Termites contribute to the micro-topographical and nutrient spatial heterogeneity of tropical forests. We therefore investigated whether epigeal termite mounds could contribute to the coexistence of plant species within a 50 ha plot at Pasoh Forest Reserve, Malaysia. Overall, stem density was significantly higher on mounds than in their immediate surroundings, but tree species diversity was significantly lower. Canonical correspondence analysis showed that location on or off mounds significantly influenced species distribution when stems were characterized by basal area. Like studies of termite mounds in other ecosystems, our results suggest that epigeal termite mounds provide a specific microhabitat for the enhanced growth and survival of certain species in these species-rich tropical forests. However, the extent to which epigeal termite mounds facilitate species coexistence warrants further investigation.

The aim of this work was to assess the virulence of strain M379 of the fungus, Metarhizium anisopliae (Metchnikoff) Sorokin (Hypocreales: Clavicipitaceae) after different passages through a suitable host and at different concentrations for the control of both acaricide-susceptible and resistant strains of the tick, Rhipicephalus (formerly Boophilus) microplus Canestrini (Ixodida:Ixodidae) in vitro. The highest value of LC50 for the susceptible strain corresponded to zero passage with 7.68 × 107 conidia/ml followed by the fourth passage with 2.68 × 107, which reduced 2.87-fold the lethal concentration. When comparing LC50 values of the fourth vs. the seventh passage (2.59 × 105 conidia/ml), the lethal concentration was reduced 103.47-fold by the seventh passage. In addition, in the resistant strain the LC50 highest value corresponded to zero passage with 4.95 × 107 conidia/ml followed by the fourth passage with 7.86 × 106, which reduced 6.30-fold the lethal concentration. When comparing LC50 values of the fourth vs. the seventh passage (1.04 × 105 conidia/ml) in the resistant strain, the lethal concentration was reduced 75.58-fold by the seventh passage. These results suggest that the number of passages on M. anisopliae through a suitable host increased its virulence on both R. microplus strains. When comparing LC50 of the zero passage through a suitable host of both acaricide-susceptible and resistant strains, the highest LC50 values corresponded to the susceptible strain with 7.68 × 107 conidia/ml followed by the resistant one with 4.95 × 107, showing that on the resistant strain the lethal concentration is reduced by 1.55-fold. When comparing the fourth passage, the highest values of LC50 corresponded to the susceptible strain with 2.68 x 107 conidia/ml followed by the resistant one with 7.86 × 106 conidia/ml, showing for the resistant strain a 3.41-fold reduced lethal concentration. Moreover, when comparing the seventh passages, the highest values of LC50 corresponded to the susceptible strain with 2.59 × 105 followed by the resistant with 1.04 × 105 conidia/ml, revealing for the resistant strain a 2.49-fold reduced lethal concentration. These results suggest that the resistant strain needs a lower concentration of conidia than the susceptible strain. In this case, the acaricide-resistant strain is more susceptible to M. anisopliae of zero- and seven-passage strains.

Modern metagenomic approaches enable the effective discovery of novel viruses in previously unexplored organisms. Termites are significant ecosystem converters and influencers. As with the majority of tropical forest insects, termites are studied insufficiently, and termite virome remains especially understudied. Here, we studied the virome of lichenophagous and mycophagous termites (Hospitalitermes bicolor, Macrotermes carbonarius and Odontotermes wallonensis) collected in the Cat Tien National Park (Vietnam). We assembled four full genomes of novel viruses related to Solemoviridae, Lispiviridae, Polycipiviridae and Kolmioviridae. We also found several contigs with relation to Chuviridae and Deltaflexiviridae that did not correspond to complete virus genomes. All the novel viruses clustered phylogenetically with previously identified viruses of the termites. Deltaflexi-like contigs were identified in the fungi-cultivating M. carbonarius and showed homology with viruses recently discovered in the edible basidiomycete mushrooms.

Hydrocarbon mixtures extracted from fecal pellets of drywood termites are species-specific and can be characterized to identify the termites responsible for damage, even when termites are no longer present or are unable to be recovered easily. In structures infested by drywood termites, it is common to find fecal pellets, but difficult to sample termites from the wood. When fecal pellets appear after remedial treatment of a structure, it is difficult to determine whether this indicates that termites in the structure are still alive and active or not. We examined the hydrocarbon composition of workers, alates, and soldiers of Incisitermes minor (Hagen) (family Kalotermitidae) and of fecal pellets of workers. Hydrocarbons were qualitatively similar among castes and pellets. Fecal pellets that were aged for periods of 0, 30, 90, and 365 days after collection were qualitatively similar across all time periods, however, the relative quantities of certain individual hydrocarbons changed over time, with 19 of the 73 hydrocarbon peaks relatively increasing or decreasing. When the sums of the positive and negative slopes of these 19 hydrocarbons were indexed, they produced a highly significant linear correlation (R 2 = 0.89). Consequently, the quantitative differences of these hydrocarbons peaks can be used to determine the age of worker fecal pellets, and thus help determine whether the colony that produced them is alive or dead.

A new species of Pericapritermes, P. travancorensis sp. nov. (Isoptera, Termitidae, Termitinae), is described from Kerala, India, based on the characters of the king, queen, imago, soldiers, and workers. Morphological measurements of the king, queen, imago, soldiers, and workers are given with suitable illustrations. List of species of the genus Pericapritermes from the Oriental region is provided.

Sex‐determination systems often show remarkable diversity in upstream signals, although downstream genes are broadly conserved. Therefore, the downstream genes have been investigated in various taxa, but the most upstream signals determining sex in insects have been well‐described mainly in model organisms, including fruit flies and honey bees, and not in hemimetabolous insects such as termites. Identification of sex‐linked genetic markers in termites is important to the survey of primary sex‐determination signals. Here, we report male‐specific alleles at the microsatellite locus NK12‐1 in the Ryukyu drywood termite Neotermes sugioi (Kalotermitidae). This study provides the third example of a genetic marker linked with sexual phenotype in termites, which is a small but important step to elucidate the evolutionary process of the sex‐determination system in termites. [ABSTRACT FROM AUTHOR]

Trail-following behavior is a key to ecological success of termites, allowing them to orient themselves between the nesting and foraging sites. This behavior is controlled by specific trail-following pheromones produced by the abdominal sternal gland occurring in all termite species and developmental stages. Trail-following communication has been studied in a broad spectrum of species, but the "higher" termites (i.e. Termitidae) from the subfamily Syntermitinae remain surprisingly neglected. To fill this gap, we studied the trail-following pheromone in six genera and nine species of Syntermitinae. Our chemical and behavioral experiments showed that (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol is the single component of the pheromone of all the termite species studied, except for Silvestritermes euamignathus. This species produces both (3Z,6Z)-dodeca-3,6-dien-1-ol and neocembrene, but only (3Z,6Z)-dodeca-3,6-dien-1-ol elicits trail-following behavior. Our results indicate the importance of (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol, the most widespread communication compound in termites, but also the repeated switches to other common pheromones as exemplified by S. euamignathus. [ABSTRACT FROM AUTHOR]

Termites comprise a large group of organisms in urban areas, and this leads us to believe that there is a comprehensive literature on the subject, sufficient for conducting a systematic review of the last years. Consequently, the aim of this study was a descriptive analysis of publications that addressed the issue of termites in urban areas between the years 1945 and 2018. For the systematic review, a literature search was initiated using the ISI Web of Science (WoS), SCOPUS (Elsevier) and SCIELO databases. In total, 180 relevant studies in the field concerning urban termites were published, out of which most (58.33%) investigated about the invasive termites, followed by studies that addressed the issue of control of pest termites (28.33%) and ecology and biodiversity (13.33%). The most studied species on the invasive termites' category was Coptotermes formosanus, which was present in 22.78% of the publications. Studies on urban termites that highlighted the importance of the control of pest termites in urban areas began in 1983. Most of them were focussed on tests with chemical products. The most tested chemical probe in different termite species was hexaflumuron. Coptotermes formosanus was the most tested, followed by Reticulitermes flavipes. The publication of studies that focus on the ecology and biodiversity of urban termites began after 1958; they compared the diversity of termites in other locations within urban areas and is distributed in a small number of papers. Some gaps in studies that may serve as suggestions for future studies and, consequently, bring new contributions and advances in the scientific knowledge of urban termites were identified and discussed. [ABSTRACT FROM AUTHOR]

Wood‐feeding, nesting and production of secondary reproductives are key determinant traits of invasive species of drywood termites, and the West Indian drywood termite Cryptotermes brevis (Walker) is one of their major examples of worldwide concern as pest species of structural lumber, furniture and other wood products. The problem and losses by this species are determined by the prevailing wood characteristics. However, despite the current widespread occurrence of this species in the tropics, except Asia, tropical wood resistance and underlying mechanisms of resistance against this termite are scarcely known. Nonetheless, wood hardness and particularly wood density were recently recognized as important underlying traits for C. brevis resistance in tropical woods, but the chemical wood constituents were not considered. Here, we assessed tropical wood resistance to the invasive termite species C. brevis and tested the relevance of their holocellulose, lignin and (total) extractive contents preventing termite infestation. Free‐choice and no‐choice tests were carried out in parallel with wood chemical characterization. Resistance to the West Indian termite varied with wood species in terms of both colonization and consumption, but only under free‐choice testing because without choice, no significant difference was detected among wood species. Regardless, none of these traits were significantly correlated with wood resistance to C. brevis. Therefore, wood physical resistance, particularly wood density, seems the main recognized determinant of tropical wood resistance against the West Indian drywood termite. The pattern of termite movement on the surface of soft, mid and hard wood was also consistent with this conclusion. [ABSTRACT FROM AUTHOR]

Termites are dominant organisms of tropical ecosystems. Their success is partly due to the diversity of their feeding substrates, from dead plant tissues to mineralised soils. The Apicotermitinae is one of the richest subfamilies of soil-feeding termites, which are traditionally classified in feeding groups according to anatomical criteria, deemed to the reveal whether species feed on organic-rich layers (group III) or on mineralised soil (group IV). Previous studies based on δ15N isotopic values showed that this subfamily's niche covers a broad range along the gradient of humification. We hypothesised that this broad feeding range could be reflected in the crop-gizzard (Cr-Gi) content and volume. We investigated 17 African species distributed between the two feeding groups. Our results showed a variation of Cr-Gi volume and a consistent composition of content among Apicotermitinae species. Some small-bodied species had a very large Cr-Gi volume relative to their size, indicating a difference in foraging behaviour. These species might use this enhanced storage capacity to forage for longer periods of time. Cr-Gi content was dominated by clay (kaolinite) suggesting that a dietary specialisation could be based on the quality of organic compounds from organo-mineral aggregates. Variations in crystalline solids (quartz) between species indicate either differences in the abundance of mineral grains between feeding patches or active discrimination among particles by foragers. The similar composition of Cr-Gi contents in afrotropical Apicotermitinae suggests that the anatomical criteria used to assign species to feeding groups III or IV are not appropriate. [ABSTRACT FROM AUTHOR]

Bark beetle outbreaks result in massive amounts of deadwood which are a significant carbon reservoir that can impact forest ecosystems. Additionally, bark beetle-introduced symbiotic fungi in beetle-generated deadwood can increase termite presence and feeding. This could alter decomposition rates and saproxylic communities of bark beetle-generated deadwood. However, the fate of bark beetle-generated deadwood after tree mortality has received little attention despite the possibility bark beetles could alter decomposition processes and deadwood residence times at landscape scales following outbreaks. We tested the hypothesis that beetle-attacked trees decompose faster than unattacked trees. In Honduras, and Mississippi and Arizona, USA, we felled one recently bark beetle-attacked and one apparently healthy conspecific tree at each site that was cut into 120 experimental logs. Logs of each tree (attacked or unattacked) were assigned one of three metal mesh covering treatments: 1) fully covered to exclude all macroinvertebrates, 2) covered from above to exclude secondary bark beetle colonization, 3) no cover to allow all detrital food web organisms. Half of all logs at each site was collected after 1 and 2 years and the density loss, insect visual damage rating, and abundance of termites, ants, and beetles was measured. Bark beetle attack had the largest impacts at higher latitude and western forests: density loss between attacked and unattacked logs was consistently higher in Arizona (Flagstaff), initially slower (year 1) in Mississippi, but faster between years 1 and 2 resulting in similar density loss after 2 years, and did not differ in Honduras. Saproxylic insect wood damage rating accounted for 30% of the variation in decomposition across sites. Thus, decomposition rates of deadwood following bark beetle attack are highly variable across their geography and likely reflect important interactions among saproxylic organisms. This has implications for forest ecology and management including forest modeling with regard to carbon cycling and maintaining biodiversity of saproxylic organisms. [Display omitted] • Bark beetles cause massive conifer tree mortality and thus deadwood globally. • Deadwood produced after bark beetle attack differs from unattacked deadwood. • Saproxylic communities are differentially affected by bark beetle attack. • Decomposition patterns may reflect a latitudinal or longitudinal gradient. • Forest ecology and management implications include carbon cycling and biodiversity. [ABSTRACT FROM AUTHOR]

Predation is a strong selective force driving the evolution of complex antipredator traits. Antipredator defences in the form of morphological or chemical weaponry, or behavioural traits, increases a prey organism's chance of survival when faced with a predator. Termites are a group of social insects that possess an arsenal of mechanical and chemical weapons to thwart attacks from vertebrate and invertebrate predators. The soldier caste of termites have a range of mandibular modifications, including snapping, piercing and crushing mandibles. Some taxa, however, have undergone mandibular regression and are entirely reliant on chemical defence. The nasute termites are one such group that have lost their mandibles and instead have a specialised cephalic appendage in which they use to eject as viscous defensive secretion. The chemical and morphological aspects of some termite defences are well-studied, but often the behavioural components of complex antipredator traits are often neglected in current studies. Thus, improving our understanding of the underlying biological and behavioural mechanisms of termite defence systems will allow us to increase our current knowledge of the evolutionary history of a complex social insect taxon. [ABSTRACT FROM AUTHOR]

Termites are important decomposer due to their ability to digest cellulose and their diverse feeding habits. Trehalase is an enzyme that hydrolyzes trehalose to glucose in insects and has an important biological role. Gut morphology of wood-feeding termites (Globitermes sulphureus, Termitinae; Microcerotermes crassus, Termitinae and Bulbitermes prabhae, Nasutitermitinae) and fungus-growing termites (Macrotermes annandalei, Macrotermitinae) that belong to the family Termitidae was determined in this study. Results indicate that wood-feeding termites have a similar gut morphology, which consists of a foregut, midgut and elongated hindgut, which is divided into four segments. More specifically the enlarged segment in the hindgut, called a paunch, is prominent in wood-feeding termites, whereas fungus-growing termites have a simpler tubular gut with a very small paunch. Trehalase activity was high in the midgut of wood-feeding termites (G. sulphureus, Mi. crassus and B. prabhae), but in the fungus-growing termite (Ma. annandalei) the highest level of activity was recorded in the hindgut. Cellulase activity (endo-β-1,4-glucanase) was detected in all gut segments with very high levels in the hindguts of B. prabhae and Ma. annandalei. Differences in the distribution of trehalase and gut morphology correspond to the phylogenetic analyses of Termitidae, which indicate that Macrotermitinae is the sister group of Termitinae and Nasutitermitinae. In addition, validamycin suppressed trehalase activity in termites in vitro and in vivo, resulting in a high mortality in wood-feeding and fungus-growing termites, indicating that trehalase inhibitors could be useful tools for termite control.

Abstract Background Thanks to specific adaptations developed over millions of years, the efficiency of lignin, cellulose and hemicellulose decomposition of higher termite symbiotic system exceeds that of many other lignocellulose utilizing environments. Especially, the examination of its symbiotic microbes should reveal interesting carbohydrate-active enzymes, which are of primary interest for the industry. Previous metatranscriptomic reports (high-throughput mRNA sequencing) highlight the high representation and overexpression of cellulose and hemicelluloses degrading genes in the termite hindgut digestomes, indicating the potential of this technology in search for new enzymes. Nevertheless, several factors associated with the material sampling and library preparation steps make the metatranscriptomic studies of termite gut prokaryotic symbionts challenging. Methods In this study, we first examined the influence of the sampling strategy, including the whole termite gut and luminal fluid, on the diversity and the metatranscriptomic profiles of the higher termite gut symbiotic bacteria. Secondly, we evaluated different commercially available kits combined in two library preparative pipelines for the best bacterial mRNA enrichment strategy. Results We showed that the sampling strategy did not significantly impact the generated results, both in terms of the representation of the microbes and their transcriptomic profiles. Nevertheless collecting luminal fluid reduces the co-amplification of unwanted RNA species of host origin. Furthermore, for the four studied higher termite species, the library preparative pipeline employing Ribo-Zero Gold rRNA Removal Kit “Epidemiology” in combination with Poly(A) Purist MAG kit resulted in a more efficient rRNA and poly-A-mRNAdepletion (up to 98.44% rRNA removed) than the pipeline utilizing MICROBExpress and MICROBEnrich kits. High correlation of both Ribo-Zero and MICROBExpresse depleted gene expression profiles with total non-depleted RNA-seq data has been shown for all studied samples, indicating no systematic skewing of the studied pipelines. Conclusions We have extensively evaluated the impact of the sampling strategy and library preparation steps on the metatranscriptomic profiles of the higher termite gut symbiotic bacteria. The presented methodological approach has great potential to enhance metatranscriptomic studies of the higher termite intestinal flora and to unravel novel carbohydrate-active enzymes.

The New World Kalotermitidae constitute about one-fourth of all termite species in this region. The geographic distributions of all fifteen kalotermitid genera are updated based on records in the University of Florida Termite Collection and in the literature. Range-appropriate exotic records of four pest species are also given. New distribution records are presented on maps, and representative soldier photographs are provided for each genus.

Cyclohexanone is a major precursor for nylon production and is also used as a pesticide solvent. In this study, cyclohexanone was evaluated as a fumigant against rice weevil adults, confused flour beetle adults, western flower thrips larvae and adults, spotted wing drosophila adults, and subterranean termite workers. Cyclohexanone fumigation was effective against all 5 insects, and there were considerable variations in susceptibility to cyclohexanone fumigation among the 5 species. At 20 °C, complete control of spotted wing drosophila adults was achieved in 1-h fumigation with 25 μl/l of cyclohexanone and complete control of eastern subterranean termite workers was achieved in 3-h fumigations with 50 μl/l dose of cyclohexanone. Stored-product insects confused flour beetle, and rice weevil adults were more tolerant to cyclohexanone fumigation. Fumigations of 24 h with 75 μl/l dose of cyclohexanone caused 100% mortality of rice weevil adults and 98% mortality of confused flower beetle adults. Even at a 100 μl/l dose, the 24-h fumigations did not achieve 100% mortality of confused flour beetle adults. At 5 °C, complete control of western flower thrips was achieved in 3- and 6-h fumigations with 100 and 50 μl/l doses of cyclohexanone, respectively. Cyclohexanone vapor concentrations were measured using cyclohexanone detector tubes. Vapor concentrations were far below the expected saturation concentration indicating that most cyclohexanone did not exist as vapor in fumigation chambers. The results of effective control of all 5 insect species suggest that cyclohexanone has the potential to be used as a fumigant for postharvest pest control., (Published by Oxford University Press on behalf of Entomological Society of America 2024.)

Termites build complex nests which are an impressive example of self-organization. We know that the coordinated actions involved in the construction of these nests by multiple individuals are primarily mediated by signals and cues embedded in the structure of the nest itself. However, to date there is still no scientific consensus about the nature of the stimuli that guide termite construction, and how they are sensed by termites. In order to address these questions, we studied the early building behavior of Coptotermes gestroi termites in artificial arenas, decorated with topographic cues to stimulate construction. Pellet collections were evenly distributed across the experimental setup, compatible with a collection mechanism that is not affected by local topography, but only by the distribution of termite occupancy (termites pick pellets at the positions where they are). Conversely, pellet depositions were concentrated at locations of high surface curvature and at the boundaries between different types of substrate. The single feature shared by all pellet deposition regions was that they correspond to local maxima in the evaporation flux. We can show analytically and we confirm experimentally that evaporation flux is directly proportional to the local curvature of nest surfaces. Taken together, our results indicate that surface curvature is sufficient to organize termite building activity and that termites likely sense curvature indirectly through substrate evaporation. Our findings reconcile the apparently discordant results of previous studies., Competing Interests: GF, AR, SD, DS, AP No competing interests declared, (© 2023, Facchini et al.)

Background: Wheat powdery mildew, caused by the biotrophic pathogen Blumeria graminis f. sp. tritici (Bgt) is a serious fungal disease. Natural metabolites produced by microorganisms are beneficial biological control agents to inhibit Bgt. In the present study, we investigated the effects of Aspergillus chevalieri BYST01 on wheat powdery mildew., Results: A strain isolated from the termite was identified as A. chevalieri BYST01 by morphological characteristics and phylogenetic analysis. The fermentation broth of BYST01 showed good biocontrol effect on the Bgt in vivo with the control efficiencies of 81.59% and 71.34% under the protective and therapeutic tests, respectively. Four known metabolites, including the main compound physcion (30 mg/L), were isolated from the fermentation broth of BYST01 extracted with ethyl acetate. Importantly, under a concentration of 0.1 mM, physcion repressed conidial germination of Bgt with an inhibition rate of 77.04% in vitro and showed important control efficiencies of 80.36% and 74.64% in vivo under the protective and therapeutic tests, respectively. Hence, the BYST01 showed important potential as a microbial cell factory for the high yield of the green natural fungicide physcion. Finally, the biosynthetic gene clusters responsible for physicon production in BYST01 was predicted by analyzing a chromosome-scale genome obtained using a combination of Illumina, PacBio, and Hi-C sequencing technologies., Conclusion: Aspergillus chevalieri BYST01 and its main metabolite physcion had a significant control effect on wheat powdery mildew. The biosynthesis pathway of physcion in BYST01 was predicted. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

Insecticide resistance is an evolved ability to survive insecticide exposure. Compared with nonsocial insects, eusocial insects have lower numbers of documented cases of resistance. Eusocial insects include beneficial and pest species that can be incidentally or purposely targeted with insecticides. The central goal of this review is to explore factors that either limit resistance or the ability to detect it in eusocial insects. We surveyed the literature and found that resistance has been documented in bees, but in other pest groups such as ants and termites, the evidence is more sparse. We suggest the path forward for better understanding eusocial resistance should include more tractable experimental models, comprehensive geographic sampling, and targeted testing of the impacts of social, symbiont, genetic, and ecological factors., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

The symbiosis between termites and their hindgut protists is mutually obligate and vertically inherited. It was established by the late Jurassic in the cockroach ancestors of termites as they transitioned to wood feeding. Since then, protist symbionts have been transmitted from host generation to host generation by proctodeal trophallaxis (anal feeding). The protists belong to multiple lineages within the eukaryotic superphylum Metamonada. Most of these lineages have evolved large cells with complex morphology, unlike the non-termite-associated Metamonada. The species richness and taxonomic composition of symbiotic protist communities varies widely across termite lineages, especially within the deep-branching clade Teletisoptera. In general, closely related termites tend to harbour closely related protists, and deep-branching termites tend to harbour deep-branching protists, reflecting their broad-scale co-diversification. A closer view, however, reveals a complex distribution of protist lineages across hosts. Some protist taxa are common, some are rare, some are widespread, and some are restricted to a single host family or genus. Some protist taxa can be found in only a few, distantly related, host species. Thus, the long history of co-diversification in this symbiosis has been complicated by lineage-specific loss of symbionts, transfer of symbionts from one host lineage to another, and by independent diversification of the symbionts relative to their hosts. This review aims to introduce the biology of this important symbiosis and serve as a gateway to the diversity and systematics literature for both termites and protists. A searchable database with all termite-protist occurrence records and taxonomic references is provided as a supplementary file to encourage and facilitate new research in this field., (© 2023 Cambridge Philosophical Society.)

Social insects maintain hygienic conditions through their social immunity behaviors. Among these behaviors, burial behavior of termites is central for protecting healthy individuals from corpses. Many factors trigger burial behavior, and it is generally believed that chemicals released by corpses, such as oleic acid, are the most important cues for triggering burial behavior in termites. However, the contribution of the olfactory system to this behavior remains unclear. Here we report an odorant binding protein (OBP) that transports oleic acid and triggers burial behavior in Coptotermes formosanus Shiraki. We demonstrated that CforOBP7 is highly expressed in the antennae of workers. Fluorescent competition binding experiments exhibited that CforOBP7 has a strong affinity for oleic acid. Furthermore, the antennal response to oleic acid was significantly reduced, and oleic acid-triggered burial behavior was also inhibited in CforOBP7-silenced termites. We conclude that CforOBP7 governs the burial behavior of C. formosanus triggered by oleic acid., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

A new polyol polyketide, named retinestatin ( 1 ), was obtained and characterized from the culture of a Streptomyces strain, which was isolated from a subterranean nest of the termite Reticulitermes speratus kyushuensis Morimoto. The planar structure of 1 was elucidated on the basis of the cumulative analysis of ultraviolet, infrared, mass spectrometry, and nuclear magnetic resonance spectroscopic data. The absolute configuration of 1 at 12 chiral centers was successfully assigned by employing a J -based configuration analysis in combination with ROESY correlations, a quantum mechanics-based computational approach to calculate NMR chemical shifts, and a 3 min flash esterification by Mosher's reagents followed by NMR analysis. Biological evaluation of retinestatin ( 1 ) using an in vitro model of Parkinson's disease revealed that 1 protected SH-SY5Y dopaminergic cells from MPP + -induced cytotoxicity, indicating its neuroprotective effects.

Fossils encompassing multiple individuals provide rare direct evidence of behavioral interactions among extinct organisms. However, the fossilization process can alter the spatial relationship between individuals and hinder behavioral reconstruction. Here, we report a Baltic amber inclusion preserving a female-male pair of the extinct termite species Electrotermes affinis . The head-to-abdomen contact in the fossilized pair resembles the tandem courtship behavior of extant termites, although their parallel body alignment differs from the linear alignment typical of tandem runs. To solve this inconsistency, we simulated the first stage of amber formation, the immobilization of captured organisms, by exposing living termite tandems to sticky surfaces. We found that the posture of the fossilized pair matches trapped tandems and differs from untrapped tandems. Thus, the fossilized pair likely is a tandem running pair, representing the direct evidence of the mating behavior of extinct termites. Furthermore, by comparing the postures of partners on a sticky surface and in the amber inclusion, we estimated that the male likely performed the leader role in the fossilized tandem. Our results demonstrate that past behavioral interactions can be reconstructed despite the spatial distortion of body poses during fossilization. Our taphonomic approach demonstrates how certain behaviors can be inferred from fossil occurrences., Competing Interests: Competing interests statement:The authors declare no competing interest.

Termites are one of the most common pests that damage wood and other cellulosic materials . Although Africa has more varieties of termite species than any other continent, few entomological studies have been conducted in Gabon. Identifying termites poses significant difficulties for entomologists. The aim of this study was to evaluate the reliability and confirm the significance of MALDI-TOF MS in identifying fresh termites collected in equatorial Africa. A total of 108 termites were collected from 13 termite nests during a field mission in 2021 in Lekedi and Bongoville, Gabon. Termites were morphologically identified and subjected to MALDI-TOF MS, then molecular analyses using the COI and 12S rRNA genes. Four termite species were morphologically identified in this study: Pseudacanthotermes militaris , Macrotermes muelleri , Macrotermes nobilis , and Noditermes indoensis . However, when using molecular biology, only three species were identified, namely Macrotermes bellicosus , P. militaris , and N. indoensis, because the specimens initially identified as M. muelleri and M. nobilis were found to be M. bellicosus . The MALDI-TOF MS spectral profiles of the termites were all of good quality, with intra-species reproducibility and inter-species specificity. The spectra of 98 termites were blind tested against our upgraded database, which included the spectra of ten termite specimens. All tested spectra were correctly matched to their respective species, with log score values (LSVs) ranging from 1.649 to 2.592. The mean LSV was 2.215 ± 0.203, and the median was 2.241. However, 95.91% (94/98) of our spectra had LSVs above 1.8. This study demonstrates how a proteomic approach can overcome termites' molecular and morphological identification limitations and serve as a useful taxonomic tool., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Hasnaoui reports financial support was provided by Mediterranean University Hospital Institute for Infectious Diseases., (© 2024 The Authors. Published by Elsevier Ltd.)

The large abundance of termites is partially achieved by their defensive abilities. Stylotermitidae represented by a single extant genus, Stylotermes, is a member of a termite group Neoisoptera that encompasses 83% of termite species and 94% of termite genera and is characterized by the presence of the frontal gland. Within Neoisoptera, Stylotermitidae represents a species-poor sister lineage of all other groups. We studied the structure of the frontal, labral and labial glands in soldiers and workers of Stylotermes faveolus, and the composition of the frontal gland secretion in S. faveolus and Stylotermes halumicus. We show that the frontal gland is a small active secretory organ in soldiers and workers. It produces a cocktail of monoterpenes in soldiers, and some of these monoterpenes and unidentified proteins in workers. The labral and labial glands are developed similarly to other termite species and contribute to defensive activities (labral in both castes, labial in soldiers) or to the production of digestive enzymes (labial in workers). Our results support the importance of the frontal gland in the evolution of Neoisoptera. Toxic, irritating and detectable monoterpenes play defensive and pheromonal functions and are likely critical novelties contributing to the ecological success of these termites., Competing Interests: Declaration of competing interest None., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Among marsupials, the endangered numbat (Myrmecobius fasciatus) is the only obligate myrmecophage with a diet comprised strictly of termites. Like many other specialised myrmecophagous mammals, numbats have a gracile and highly specialised skull morphology with an elongated rostrum and small braincase. Myrmecobiidae is one of four taxonomic families within the Australasian marsupial order Dasyuromorphia, and to date, the muscular anatomy of any member of this group is relatively poorly known. We utilised microdissection and contrast-enhanced microcomputed tomography scanning to provide the first comprehensive qualitative and quantitative descriptions of jaw muscle anatomy in numbats and quolls (Dasuyrus species). The arrangement of the jaw muscles across these species was conservative, both in gross anatomy and muscle proportions, corresponding to a 'generalised' mammalian pattern. In contrast to Dasyurus, the jaw muscles of the numbat were greatly reduced. Many aspects of the muscle anatomy of the numbat were similar to patterns reported in other myrmecophagous species, particularly a greatly reduced temporalis muscle. Unusually, the digastric muscle in the numbat was comprised of a single, large anterior belly while the posterior belly was absent. We propose that the enlarged anterior belly of the digastric may be linked to jaw stabilisation and coordination of tongue movements during feeding. The lateral insertion and fascial connection of the digastric to the tongue in numbats may also aid in distributing stress evenly across the jaw and minimise muscle fatigue. The muscle descriptions and three-dimensional models provided in this study will facilitate further analysis of musculoskeletal adaptation and evolution within the Dasyuromorphia., (© 2024 The Authors. Journal of Morphology published by Wiley Periodicals LLC.)

Background: To control subterranean termite pests, chitin synthesis inhibitor (CSI) baits have been widely applied. Despite CSI baits having low impacts on the environment, they require a lengthy time period to eliminate colonies. 20-hydroxyecdysone (20E) was proposed to speed up the baiting process as it showed faster mortality than CSI baits. However, the efficacy of 20E has previously not been tested at the colony level prior to applying in the field., Results: We compared the effect of 20E, 20E + noviflumuron, noviflumuron and untreated control using colonies of Coptotermes formosanus. Our result revealed that both 20E and 20E + noviflumuron did not accelerate colony elimination and termite activity remained relatively stable during the observation periods. To determine the limited effects of 20E, we further investigated feeding duration and consumption amount of 20E with different concentrations (control, 100 and 1000 ppm) for 10 days. Termites ceased feeding after 1 day in 100 and 1000 ppm treatment and 100% mortality was observed within 10 days in 1000 ppm 20E, while mortality in the 100 ppm 20E treated group was much lower than that in the 1000 ppm group. Furthermore, no termites molted in the control and termites died from hyperecdysonism in 1000 ppm 20E treatment, whereas about 20% of termites molted in 100 ppm 20E., Conclusion: This study demonstrated that 20E may not be suitable as a sole active ingredient to accelerate elimination of a subterranean termite colony, while CSI baits and lower concentrations of 20E may reduce the lengthy time period in colony elimination. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

The spermatheca and colleterial glands of female insects are organs associated with the reproductive system, responsible for sperm storage and secretion of egg coverings, respectively. Here we compared the development, secretory activity, and chemical nature of the secretion in the spermatheca and colleterial glands of different-aged females of the drywood termite Cryptotermes brevis. We also provide the ultrastructure of these organs in alate females. These structures have been poorly investigated in termites when compared to other eusocial insects (Hymenoptera) and termite-related dictyopterans (mantises and cockroaches). The spermatheca of C. brevis comprises a cone-shaped structure, connected to the genital chamber by a short duct. The colleterial glands, in turn, are divided into anterior and posterior tubules, each showing a basal trunk, and join into a common duct. Histological and histochemical analyses showed that the secretion of proteins and polysaccharides by the spermatheca takes place before pairing, but increases as females mate and store sperm. Colleterial glands of alates showed non-synchronous secretory activity, but the synthesis of products increased in egg-laying queens, together with the epithelium height. Ultrastructure of the spermatheca and colleterial glands revealed epithelia composed of class III secretory cells. Richness of mitochondria and electron-dense secretion in the spermatheca indicates synthesis and transport of content. Presence and absence of colleterial gland secretion in different individuals may reflect variable maturation stages of the females and secretory cells. Assuming that termites are iteroparous, the development and secretion of the spermatheca and colleterial glands play a crucial role for C. brevis queens., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Reticulitermes flavipes , one of the most destructive subterranean termite species, has been detected for the first time in an arid territory: Lanzarote (Canary Islands, Spain). This invasive species was introduced into several countries but never such a dry region. Although there are places with presence of this termite at similar or even higher temperatures, none has annual rainfall (10.1 mm) as low as Lanzarote. On this island it is present in semi-desert, near an affected urban area. Distribution, genetic, climate and host-plant data are evaluated to track and understand its invasion process in the archipelago., Competing Interests: Juan Pestano is employed by Tragsatec and David Mora is employed by Anticimex España., (© 2024 Hernández-Teixidor et al.)

A dominant syndrome of the Anthropocene is the rapid worldwide spread of invasive species with devastating environmental and socio-economic impacts. However, the dynamics underlying the impacts of biological invasions remain contested. A hypothesis posits that the richness of impactful invasive species increases proportionally with the richness of non-native species more generally. A competing hypothesis suggests that certain species features disproportionately enhance the chances of non-native species becoming impactful, causing invasive species to arise disproportionately relative to the numbers of non-native species. We test whether invasive species with reported monetary costs reflect global numbers of established non-native species among phyla, classes, and families. Our results reveal that numbers of invasive species with economic costs largely reflect non-native species richness among taxa (i.e., in 96 % of families). However, a few costly taxa were over- and under-represented, and their composition differed among environments and regions. Chordates, nematodes, and pathogenic groups tended to be the most over-represented phyla with reported monetary costs, with mammals, insects, fungi, roundworms, and medically-important microorganisms being over-represented classes. Numbers of costly invasive species increased significantly with non-native richness per taxon, while monetary cost magnitudes at the family level were also significantly related to costly invasive species richness. Costs were biased towards a few 'hyper-costly' taxa (such as termites, mosquitoes, cats, weevils, rodents, ants, and asters). Ordination analysis revealed significant dissimilarity between non-native and costly invasive taxon assemblages. These results highlight taxonomic groups which harbour disproportionately high numbers of costly invasive species and monetary cost magnitudes. Collectively, our findings support prevention of arrival and containment of spread of non-native species as a whole through effective strategies for mitigation of the rapidly amplifying impacts of invasive species. Yet, the hyper- costly taxa identified here should receive greater focus from managers to reduce impacts of current invasive species., Competing Interests: Declaration of competing interest Ross Cuthbert reports financial support was provided by Leverhulme Trust., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Sulfuryl fluoride (SF) is a fumigant used to eliminate drywood termites (DWT: Kalotermitidae; Froggatt) and other structural pests. Because of its global warming potential, it has been suggested that SF be restricted as a greenhouse gas (GHG). We present an economic model to assess the net social cost of restricting SF. We consider 3 approaches to address DWT control- no treatment, allowing SF fumigation and localized treatments, and only local treatment. Each approach generates private and public benefits and costs. We estimate that the annual damage and home equity loss by DWT in California is US$4.5-16.8 billion without treatment. If fumigation is used on 20% of the houses and local treatments on the others, the combined social cost of treatment, damage, and GHG emissions are between US$1-US$2 billion annually. The annual cost of local treatments only would be between US$3.2 and US$4.9 billion. If the application of SF is severely restricted or banned, the social costs will increase between US$1.43 and US$4.31 billion annually. The implied cost per ton of CO2 eliminated is between US$624 and US$1,465, much above the price range of CO2 in other applications. The restriction/ban has significant equity and environmental effects, impacting low-income individuals living in rented properties and replacing damaged wood in housing will increase GHG emissions. We further recommend the continued use of SF until a comparable whole-structure alternative is developed that fits the parameters of our model., (© The Author(s) 2023. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Termite queens and kings live longer than nonreproductive workers. Several molecular mechanisms contributing to their long lifespan have been investigated; however, the underlying biochemical explanation remains unclear. Coenzyme Q (CoQ), a component of the mitochondrial electron transport chain, plays an essential role in the lipophilic antioxidant defense system. Its beneficial effects on health and longevity have been well studied in several organisms. Herein, we demonstrated that long-lived termite queens have significantly higher levels of the lipophilic antioxidant CoQ 10 than workers. Liquid chromatography analysis revealed that the levels of the reduced form of CoQ 10 were 4 fold higher in the queen's body than in the worker's body. In addition, queens showed 7 fold higher levels of vitamin E, which plays a role in antilipid peroxidation along with CoQ, than workers. Furthermore, the oral administration of CoQ 10 to termites increased the CoQ 10 redox state in the body and their survival rate under oxidative stress. These findings suggest that CoQ 10 acts as an efficient lipophilic antioxidant along with vitamin E in long-lived termite queens. This study provides essential biochemical and evolutionary insights into the relationship between CoQ 10 concentrations and termite lifespan extension., (© 2023 Institute of Zoology, Chinese Academy of Sciences.)

Termites are eusocial insects having evolved several feeding, nesting and reproductive strategies. Among them, inquiline termites live in a nest built by other termite species: some of them do not forage outside the nest, but feed on food stored by the host or on the nest material itself. In this study, we characterized some dimensions of the ecological niche of Cavitermes tuberosus (Termitidae: Termitinae), a broad-spectrum inquiline termite with a large neotropical distribution, to explain its ecological success. We used an integrative framework combining ecological measures (physico-chemical parameters, stable isotopic ratios of N and C) and Illumina MiSeq sequencing of 16S rRNA gene to identify bacterial communities and to analyse termites as well as the material from nests constructed by different termite hosts (the builders). Our results show that (1) nests inhabited by C. tuberosus display a different physico-chemical composition when compared to nests inhabited by its builder alone; (2) stable isotopic ratios suggest that C. tuberosus feeds on already processed, more humified, nest organic matter; and (3) the gut microbiomes cluster by termite species, with the one of C. tuberosus being much more diverse and highly similar to the one of its main host, Labiotermes labralis. These results support the hypothesis that C. tuberosus is a generalist nest feeder adapted to colonize nests built by various builders, and explain its ecological success. [ABSTRACT FROM AUTHOR]