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The higher classification of termites requires substantial revision as the Neoisoptera, the most diverse termite lineage, comprise many paraphyletic and polyphyletic higher taxa. Here, we produce an updated termite classification using genomic-scale analyses. We reconstruct phylogenies under diverse substitution models with ultraconserved elements analyzed as concatenated matrices or within the multi-species coalescence framework. Our classification is further supported by analyses controlling for rogue loci and taxa, and topological tests. We show that the Neoisoptera are composed of seven family-level monophyletic lineages, including the Heterotermitidae Froggatt, Psammotermitidae Holmgren, and Termitogetonidae Holmgren, raised from subfamilial rank. The species-rich Termitidae are composed of 18 subfamily-level monophyletic lineages, including the new subfamilies Crepititermitinae, Cylindrotermitinae, Forficulitermitinae, Neocapritermitinae, Protohamitermitinae, and Promirotermitinae; and the revived Amitermitinae Kemner, Microcerotermitinae Holmgren, and Mirocapritermitinae Kemner. Building an updated taxonomic classification on the foundation of unambiguously supported monophyletic lineages makes it highly resilient to potential destabilization caused by the future availability of novel phylogenetic markers and methods. The taxonomic stability is further guaranteed by the modularity of the new termite classification, designed to accommodate as-yet undescribed species with uncertain affinities to the herein delimited monophyletic lineages in the form of new families or subfamilies.

De aanwezigheid van een eerste termietensoort in Nederland is nog maar net gemeld, of we kunnen al een tweede soort bijschrijven. In Rotterdam is in 2021 een kolonie van de Pacifische nathouttermiet ontdekt. Onderzoek heeft nu aangetoond dat het niet blijft bij een per ongeluk geïmporteerde kolonie, maar dat de soort zich heeft uitgebreid.

Voor het eerst is in Nederland een gevestigde termietenkolonie vastgesteld. De kolonie is al in 2019 vastgesteld, maar pas dit jaar onderzocht. Het betreft een soort die erg schadelijk is voor (constructie)hout: de Amerikaanse grondtermiet. Deze exoot leeft al in meerdere landen in Europa, maar komt van origine uit Noord-Amerika. Na deze ontdekking zijn nóg twee termietenkolonies aangetroffen.

De kans op vestiging van termieten in Nederland is groot. Een vestiging kan tot grote maatschappelijke kosten leiden. Geconstateerd wordt dat er in ons land geen beleidsmatig of wettelijke kader is dat betrekking heeft op termieten. Ga het gesprek aan met collega overheden om de rol te bepalen van de verschillende partijen bij signalering en bestrijding van termieten. Dit advies geeft BuRO aan de directeur van directie Natuur, ministerie van Landbouw, Natuur en Voedselkwaliteit.

Online informatieblad over termieten.

Cedrus atlantica is a tree species present in the south of France which, in the context of climate change, could become a conservation priority in the coming years. This tree species is also of considerable ecological and socio-economic interest in the Mediterranean Basin area, where it is mainly recognized for its durable timber, and also for the potentially interesting chemical properties of its essential oil. Studies of its heartwood formation process and the properties of its extractive compounds are therefore of interest, although very few have been conducted so far. The radial distribution of water/acetone extractives within the Atlas cedar tree (bark, sapwood, transition wood, outer heartwood and inner heartwood) selected for this study was screened at different tree height levels. High-performance liquid chromatography (HPLC) analyses were performed, especially to characterize flavonoid compounds in these extractive fractions. The radial variation of the extractive composition obtained highlights the phenomenon of heartwood formation. Assumptions were put forward as to the metabolic pathways involved in the heartwood formation process of cedar wood, based in particular on the occurrence and radial evolution of (-)-catechin, (+)-taxifolin and flavan compounds. The fungicidal and termite-repellent activities of the extracts were then tested. The water/acetone extractives from the Cedrus atlantica individual studied showed strong termite repellent activity and moderate antifungal activity against crop and fruit pathogens. Even though the sampling in this study was limited to a single tree, the results point to a potential for commercial use of Atlas cedar extractives as wood preservatives and/or as biocontrol products against pathogens of ligneous agricultural crops. Additional tests and chemical analyses will be carried out to confirm these interesting preliminary results.

In termites with a true worker caste, the development pattern splits up from early developmental stages: primary reproductives develop through the nymphal line, whereas workers and soldiers follow the apterous developmental line. In some species, such as Cavitermes tuberosus Emerson (Isoptera: Termitidae, Termitinae), secondary reproductives (or neotenics) may also develop through the nymphal line from a transitional stage called aspirant. Aspirants originate mostly from automictic parthenogenetic reproduction. Therefore, C. tuberosus queens originate from sexual (primary queens) or parthenogenetic (neotenic queens) reproduction. A comparison of these two queen castes offers the possibility to better understand core molecular underpinnings of caste development and plasticity in termites. We investigated these molecular mechanisms by using high-throughput Illumina RNA sequencing of pooled individuals. We first assembled the de novo reference transcriptome of C. tuberosus, and then identified the transcripts consistently co-expressed across castes, sexes, and two alternative routes to female reproduction. Cavitermes tuberosus final transcriptome had 130 874 transcripts, N50 of 3398, and total length of 213 549 184 bp. We found that female reproductive maturation was characterized by gene expression down-regulation: primary queens expressed fewer transcripts overall and had the greatest number of down-regulated transcripts when compared to all other castes. In both secondary and primary queens, biological processes involved in muscle development and contraction, flight, and olfactory learning were enriched in the down-regulated gene cluster. In contrast, processes related to reproductive development, insulin receptor signaling pathway, isoprenoid biosynthesis, and multiple metabolic processes were enriched among up-regulated genes in primary queens. Finally, we found that 17% of all transcripts (21852) were differently co-expressed when females from sexual and partheno, SCOPUS: ar.j, info:eu-repo/semantics/published

Zo nu en dan krijgt het KAD kleine, bruine kevertjes ter determinatie aangeboden die binnen zijn aangetroffen. Aangezien er enkele bruine keversoorten bekend zijn die schade kunnen aanbrengen binnenshuis (zoals voorraadaantastende en houtaantastende kevers), snappen wij dat zo’n aangetroffen kever tot ongerustheid kan leiden bij de melders. Gelukkig kunnen we de melders na determinatie vaak geruststellen dat het gaat om moerasweekschilden (Scirtidae), ook wel moerasvlokevers genoemd.

Cryptotermes brevis (Walker, 1853) (Kalotermitidae), commonly called the West Indian drywood termite, is an important structural pest in many parts of the world. Almost all records of C. brevis come from timber or furniture inside human structures. Although originally described for Jamaica, this species appears to be native to the coastal desert area of Peru and Chile, where it commonly occurs outdoors in the dead wood of both living and dead trees in riparian habitats and irrigated agricultural areas. Here, we report outdoor records of C. brevis from an agricultural habitat at the western edge of the Sahara Desert, an area climatically similar to their native range in South America. This constitutes the first outdoor report of the invasive termite in the Old World. In Dakhla, Moroccan Sahara, we found these termites living in the dead wood of a Brazilian peppertree (Schinus terebinthifolia Raddi) and the hollow stems of giant reeds (Arundo donax L.). In North Africa, C. brevis is otherwise known only from structural timbers in northern Egypt. Whether this termite become a significant pest in North Africa remains to be seen.

Knowledge of the wood properties of tropi- cal tree species is still relatively limited, so timber extraction focuses on a few abun- dant, large-diameter species. Very little is known about small-diameter trees, although they could be used directly as roundwood for construction. The aim of this study was to determine the natural durability of 8 candi- date species for use as structural roundwood in French Guiana: Goupia glabra, Licania alba, Hymenopus heteromorphus, Lecythis per- sistens, Oxandra asbeckii, Pouteria bangii, Simarouba amara, Tachigali melinonii and Virola surinamensis. Samples of their wood were exposed to white rot (European and tro- pical), brown rot (European), and European subterranean termites (using non-choice and multi-choice tests) in laboratory conditions and subjected to screening tests adapted from European standards. Only two species were classified as durable against both fungi and termites: L. alba and P. bangii, which means they can be used without treatment as buil- ding material in tropical or temperate climates. The other species tested were classified (1) as durable but with notable differences observed in their resistance to fungi and termites res- pectively (G. glabra, L. persistens, O. asbeckii), (2) moderately durable (H. heteromorphus), (3) low durability to sensitive (T. melinonii, S. amara, V. surinamensis), meaning actual European standards would not let use these last species in outdoor structures without pro- tection, despite their use by local population in traditional building. However, they could be used for building purposes with appropriate protection systems (including wood protec- tion). The results we obtained for resistance to wood decay provide essential information to assess the potential of these eight tree species in French Guiana's construction sector.

Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing >6.8 times per 10°C increase in temperature)-even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth's surface.

Soil-feeding termites are abundant in tropical regions and play an important role in soil bioturbation and in the organic matter cycle. The Apicotermitinae are arguably the most diverse lineage of soil-feeding termites, but they are also the most understudied, probably because many species are soldierless, which makes identification difficult. Although the backbone of the termite phylogenetic tree is now well-resolved, the relationships among representatives of Apicotermitinae are still largely unknown. Here, we present phylogenetic trees inferred from 113 mitochondrial genomes of Apicotermitinae representative of the group diversity. Our analyses confirm the monophyly of the Apicotermitinae and the basal position of soldiered taxa, within which two lineages of soldierless species are nested. We describe two new monotypic genera, whose phylogenetic position appeared of special interest: Koutabatermes gen. n., lies on a long branch among soldiered taxa, and Apolemotermes gen. n., is sister to Adaiphrotermes. We resolved, with high support, the position of Asian genera as sister group of a clade comprising the monophyletic neotropical Anoplotermes-group and the small African clade including Adaiphrotermes and Apolemotermes gen. n.. Our trees cast light on the intergeneric and interspecific relationships within Apicotermitinae and reveal the polyphyly of several genera, including Ruptitermes, Astalotermes and Anoplotermes. Biogeographic reconstructions revealed two dispersal events out of Africa, one to the Oriental realm and one to the Neotropical realm. Overall, the timing of Apicotermitinae diversification and dispersal, following the Eocene–Oligocene boundary, matches that found for other groups of Neoisoptera. Nomenclatural acts are registered in ZooBank: http://zoobank.org/urn:lsid:zoobank.org:pub:CA1A21B6-573E-4855-8C88-372453C922F7., source:https://resjournals.onlinelibrary.wiley.com/doi/10.1111/syen.12486

BackgroundTermites primarily feed on lignocellulose or soil in association with specific gut microbes. The functioning of the termite gut microbiota is partly understood in a handful of wood-feeding pest species but remains largely unknown in other taxa. We intend to fill this gap and provide a global understanding of the functional evolution of termite gut microbiota.ResultsWe sequenced the gut metagenomes of 145 samples representative of the termite diversity. We show that the prokaryotic fraction of the gut microbiota of all termites possesses similar genes for carbohydrate and nitrogen metabolisms, in proportions varying with termite phylogenetic position and diet. The presence of a conserved set of gut prokaryotic genes implies that essential nutritional functions were present in the ancestor of modern termites. Furthermore, the abundance of these genes largely correlated with the host phylogeny. Finally, we found that the adaptation to a diet of soil by some termite lineages was accompanied by a change in the stoichiometry of genes involved in important nutritional functions rather than by the acquisition of new genes and pathways.ConclusionsOur results reveal that the composition and function of termite gut prokaryotic communities have been remarkably conserved since termites first appeared ~ 150 million years ago. Therefore, the “world’s smallest bioreactor” has been operating as a multipartite symbiosis composed of termites, archaea, bacteria, and cellulolytic flagellates since its inception., source:https://microbiomejournal.biomedcentral.com/articles/10.1186/s40168-022-01258-3

The phylogenetic history of termites has been investigated using mitochondrial genomes and transcriptomes. However, both sets of markers have specific limitations. Mitochondrial genomes represent a single genetic marker likely to yield phylogenetic trees presenting incongruences with species trees, and transcriptomes can only be obtained from well-preserved samples. In contrast, ultraconserved elements (UCEs) include a great many independent markers that can be retrieved from poorly preserved samples. Here, we designed termite-specific baits targeting 50,616 UCE loci. We tested our UCE bait set on 42 samples of termites and three samples of Cryptocercus, for which we generated low-coverage highly-fragmented genome assemblies and successfully extracted in silico between 3,426 to 42,860 non-duplicated UCEs per sample. Our maximum likelihood phylogenetic tree, reconstructed using the 5,934 UCE loci retrieved from upward of 75% of samples, was congruent with transcriptome-based phylogenies, demonstrating that our UCE bait set is reliable and phylogenetically informative. Combined with non-destructive DNA extraction protocols, our UCE bait set provides the tool needed to carry out a global taxonomic revision of termites based on poorly preserved specimens such as old museum samples. The Termite UCE database is maintained at: https://github.com/oist/TER-UCE-DB/., source:https://www.sciencedirect.com/science/article/pii/S1055790322001336

Fungus-farming termites have a mutualist association with fungi of the genus Termitomyces and gut microbiota to support the nearly complete decomposition of lignocellulose to gain access to nutrients. This elaborate strategy of plant biomass digestion makes them ecologically successful dominant decomposers in (sub)tropical Old World ecosystems.Fungus-growing termites are efficient in degrading and digesting plant substrates, achieved through the engagement of symbiotic gut microbiota and lignocellulolytic Termitomyces fungi cultivated for protein-rich food. Insights into where specific plant biomass components are targeted during the decomposition process are sparse. In this study, we performed several analytical approaches on the fate of plant biomass components and did amplicon sequencing of the 16S rRNA gene to investigate the lignocellulose digestion in the symbiotic system of the fungus-growing termite Odontotermes formosanus (Shiraki) and to compare bacterial communities across the different stages in the degradation process. We observed a gradual reduction of lignocellulose components throughout the process. Our findings support that the digestive tract of young workers initiates the degradation of lignocellulose but leaves most of the lignin, hemicellulose, and cellulose, which enters the fresh fungus comb, where decomposition primarily occurs. We found a high diversity and quantity of monomeric sugars in older parts of the fungus comb, indicating that the decomposition of lignocellulose enriches the old comb with sugars that can be utilized by Termitomyces and termite workers. Amplicon sequencing of the 16S rRNA gene showed clear differences in community composition associated with the different stages of plant biomass decomposition which could work synergistically with Termitomyces to shape the digestion process. IMPORTANCE Fungus-farming termites have a mutualist association with fungi of the genus Termitomyces and gut microbiota to support the

Fungus-farming termites have a mutualist association with fungi of the genus Termitomyces and gut microbiota to support the nearly complete decomposition of lignocellulose to gain access to nutrients. This elaborate strategy of plant biomass digestion makes them ecologically successful dominant decomposers in (sub)tropical Old World ecosystems.Fungus-growing termites are efficient in degrading and digesting plant substrates, achieved through the engagement of symbiotic gut microbiota and lignocellulolytic Termitomyces fungi cultivated for protein-rich food. Insights into where specific plant biomass components are targeted during the decomposition process are sparse. In this study, we performed several analytical approaches on the fate of plant biomass components and did amplicon sequencing of the 16S rRNA gene to investigate the lignocellulose digestion in the symbiotic system of the fungus-growing termite Odontotermes formosanus (Shiraki) and to compare bacterial communities across the different stages in the degradation process. We observed a gradual reduction of lignocellulose components throughout the process. Our findings support that the digestive tract of young workers initiates the degradation of lignocellulose but leaves most of the lignin, hemicellulose, and cellulose, which enters the fresh fungus comb, where decomposition primarily occurs. We found a high diversity and quantity of monomeric sugars in older parts of the fungus comb, indicating that the decomposition of lignocellulose enriches the old comb with sugars that can be utilized by Termitomyces and termite workers. Amplicon sequencing of the 16S rRNA gene showed clear differences in community composition associated with the different stages of plant biomass decomposition which could work synergistically with Termitomyces to shape the digestion process. IMPORTANCE Fungus-farming termites have a mutualist association with fungi of the genus Termitomyces and gut microbiota to support the

Background: Termites primarily feed on lignocellulose or soil in association with specific gut microbes. The functioning of the termite gut microbiota is partly understood in a handful of wood-feeding pest species but remains largely unknown in other taxa. We intend to fill this gap and provide a global understanding of the functional evolution of termite gut microbiota. Results: We sequenced the gut metagenomes of 145 samples representative of the termite diversity. We show that the prokaryotic fraction of the gut microbiota of all termites possesses similar genes for carbohydrate and nitrogen metabolisms, in proportions varying with termite phylogenetic position and diet. The presence of a conserved set of gut prokaryotic genes implies that essential nutritional functions were present in the ancestor of modern termites. Furthermore, the abundance of these genes largely correlated with the host phylogeny. Finally, we found that the adaptation to a diet of soil by some termite lineages was accompanied by a change in the stoichiometry of genes involved in important nutritional functions rather than by the acquisition of new genes and pathways. Conclusions: Our results reveal that the composition and function of termite gut prokaryotic communities have been remarkably conserved since termites first appeared ~ 150 million years ago. Therefore, the “world’s smallest bioreactor” has been operating as a multipartite symbiosis composed of termites, archaea, bacteria, and cellulolytic flagellates since its inception. [MediaObject not available: see fulltext.]., SCOPUS: ar.j, info:eu-repo/semantics/published

Kings and queens of eusocial termites can live for decades, while queens sustain a nearly maximal fertility. To investigate the molecular mechanisms underlying their long lifespan, we carried out transcriptomics, lipidomics and metabolomics in Macrotermes natalensis on sterile short-lived workers, long-lived kings and five stages spanning twenty years of adult queen maturation. Reproductives share gene expression differences from workers in agreement with a reduction of several aging-related processes, involving upregulation of DNA damage repair and mitochondrial functions. Anti-oxidant gene expression is downregulated, while peroxidability of membranes in queens decreases. Against expectations, we observed an upregulated gene expression in fat bodies of reproductives of several components of the IIS pathway, including an insulin-like peptide, Ilp9. This pattern does not lead to deleterious fat storage in physogastric queens, while simple sugars dominate in their hemolymph and large amounts of resources are allocated towards oogenesis. Our findings support the notion that all processes causing aging need to be addressed simultaneously in order to prevent it.

Macrotermitine termites have domesticated fungi in the genus Termitomyces as their primary food source using predigested plant biomass. To access the full nutritional value of lignin-enriched plant biomass, the termite-fungus symbiosis requires the depolymerization of this complex phenolic polymer. While most previous work suggests that lignocellulose degradation is accomplished predominantly by the fungal cultivar, our current understanding of the underlying biomolecular mechanisms remains rudimentary. Here, we provide conclusive omics and activity-based evidence that Termitomyces employs not only a broad array of carbohydrate-active enzymes (CAZymes) but also a restricted set of oxidizing enzymes (manganese peroxidase, dye decolorization peroxidase, an unspecific peroxygenase, laccases, and aryl-alcohol oxidases) and Fenton chemistry for biomass degradation. We propose for the first time that Termitomyces induces hydroquinone-mediated Fenton chemistry (Fe2+ + H2O2 + H+ → Fe3+ + •OH + H2O) using a herein newly described 2-methoxy-1,4-dihydroxybenzene (2-MH2Q, compound 19)-based electron shuttle system to complement the enzymatic degradation pathways. This study provides a comprehensive depiction of how efficient biomass degradation by means of this ancient insects agricultural symbiosis is accomplished. IMPORTANCE Fungus-growing termites have optimized the decomposition of recalcitrant plant biomass to access valuable nutrients by engaging in a tripartite symbiosis with complementary contributions from a fungal mutualist and a codiversified gut microbiome. This complex symbiotic interplay makes them one of the most successful and important decomposers for carbon cycling in Old World ecosystems. To date, most research has focused on the enzymatic contributions of microbial partners to carbohydrate decomposition. Here, we provide genomic, transcriptomic, and enzymatic evidence that Termitomyces also employs redox mechanisms, including diverse ligninolytic enzymes and

Termites are important ecosystem engineers in tropical habitats, with different feeding groups able to decompose wood, grass, litter, and soil organic matter. In most tropical regions, termite abundance and species diversity are assumed to increase with rainfall, with highest levels found in rainforests. However, in the Australian tropics, this pattern is thought to be reversed, with lower species richness and termite abundance found in rainforest than drier habitats. The potential mechanisms underlying this pattern remain unclear. We compared termite assemblages (abundance, activity, diversity, and feeding group composition) across five sites along a precipitation gradient (ranging from ∼800 to 4,000 mm annual rainfall), spanning dry and wet savanna habitats, wet sclerophyll, and lowland and upland rainforests in tropical North Queensland. Moving from dry to wet habitats, we observed dramatic decreases in termite abundance in both mounds and dead wood occupancy, with greater abundance and activity at savanna sites (low precipitation) compared with rainforest or sclerophyll sites (high precipitation). We also observed a turnover in termite species and feeding group diversity across sites that were close together, but in different habitats. Termite species and feeding group richness were highest in savanna sites, with 13 termite species from wood-, litter-, grass-, dung-, and soil-feeding groups, while only five termite species were encountered in rainforest and wet sclerophyll sites—all wood feeders. These results suggest that the Australian termite diversity anomaly may be partly driven by how specific feeding groups colonized habitats across Australia. Consequently, termites in Australian rainforests may be less important in ecosystem processes, such as carbon and nutrient cycling during decomposition, compared with termites in other tropical rainforests.

Termites play a major role in a variety of ecological processes in tropical and subtropical biomes worldwide, such as decomposition, soil formation and aeration, and nutrient cycling. These important ecosystem services were achieved through their highly complex societies and remarkable adaptations, including the evolution of reproductive division of labour, the acquisition of endosymbionts and the capacity for extensive environmental engineering, yet the causes and consequences of their ecological success are still poorly understood. The goals of our study were (a) to provide the first complete, species-level phylogeny of all currently recognized termite species by integrating the available genetic and taxonomic data, as well as methods of phylogenetic imputation and divergence time estimation; and (b) to explore variation in speciation rates among termite lineages. We provide the inferred relationships as a set of 1,000 pseudo-posterior trees, which can be used in future comparative analyses. We demonstrate that speciation rates have been relatively constant throughout the history of termites, with two positive shifts in speciation rates: one at their origin of Euisoptera and the other concordant with evolution of Termitidae. On the other hand, there was no obvious trend towards deceleration in speciation rates for termites as a whole, nor within the most species-rich families. The provided trees might represent a valuable resource for termite comparative studies by summarizing the available phylogenetic information, while accounting for uncertainty in the inferred topologies.

Termites are important ecosystem engineers in tropical habitats, with different feeding groups able to decompose wood, grass, litter, and soil organic matter. In most tropical regions, termite abundance and species diversity are assumed to increase with rainfall, with highest levels found in rainforests. However, in the Australian tropics, this pattern is thought to be reversed, with lower species richness and termite abundance found in rainforest than drier habitats. The potential mechanisms underlying this pattern remain unclear. We compared termite assemblages (abundance, activity, diversity, and feeding group composition) across five sites along a precipitation gradient (ranging from ∼800 to 4,000 mm annual rainfall), spanning dry and wet savanna habitats, wet sclerophyll, and lowland and upland rainforests in tropical North Queensland. Moving from dry to wet habitats, we observed dramatic decreases in termite abundance in both mounds and dead wood occupancy, with greater abundance and activity at savanna sites (low precipitation) compared with rainforest or sclerophyll sites (high precipitation). We also observed a turnover in termite species and feeding group diversity across sites that were close together, but in different habitats. Termite species and feeding group richness were highest in savanna sites, with 13 termite species from wood-, litter-, grass-, dung-, and soil-feeding groups, while only five termite species were encountered in rainforest and wet sclerophyll sites—all wood feeders. These results suggest that the Australian termite diversity anomaly may be partly driven by how specific feeding groups colonized habitats across Australia. Consequently, termites in Australian rainforests may be less important in ecosystem processes, such as carbon and nutrient cycling during decomposition, compared with termites in other tropical rainforests.

Stable isotope analysis is an increasingly used molecular tool to reconstruct the diet and ecology of elusive primates such as unhabituated chimpanzees. The consumption of C4 plant feeding termites by chimpanzees may partly explain the relatively high carbon isotope values reported for some chimpanzee communities. However, the modest availability of termite isotope data as well as the diversity and cryptic ecology of termites potentially consumed by chimpanzees obscures our ability to assess the plausibility of these termites as a C4 resource. Here we report the carbon and nitrogen isotope values from 79 Macrotermes termite samples from six savanna woodland chimpanzee research sites across equatorial Africa. Using mixing models, we estimated the proportion of Macrotermes C4 plant consumption across savanna woodland sites. Additionally, we tested for isotopic differences between termite colonies in different vegetation types and between the social castes within the same colony in a subset of 47 samples from 12 mounds. We found that Macrotermes carbon isotope values were indistinguishable from those of C3 plants. Only 5 to 15% of Macrotermes diets were comprised of C4 plants across sites, suggesting that they cannot be considered a C4 food resource substantially influencing the isotope signatures of consumers. In the Macrotermes subsample, vegetation type and caste were significantly correlated with termite carbon values, but not with nitrogen isotope values. Large Macrotermes soldiers, preferentially consumed by chimpanzees, had comparably low carbon isotope values relative to other termite castes. We conclude that Macrotermes consumption is unlikely to result in high carbon isotope values in either extant chimpanzees or fossil hominins.

Termites play a major role in a variety of ecological processes in tropical and subtropical biomes worldwide, such as decomposition, soil formation and aeration, and nutrient cycling. These important ecosystem services were achieved through their highly complex societies and remarkable adaptations, including the evolution of reproductive division of labour, the acquisition of endosymbionts and the capacity for extensive environmental engineering, yet the causes and consequences of their ecological success are still poorly understood. The goals of our study were (a) to provide the first complete, species-level phylogeny of all currently recognized termite species by integrating the available genetic and taxonomic data, as well as methods of phylogenetic imputation and divergence time estimation; and (b) to explore variation in speciation rates among termite lineages. We provide the inferred relationships as a set of 1,000 pseudo-posterior trees, which can be used in future comparative analyses. We demonstrate that speciation rates have been relatively constant throughout the history of termites, with two positive shifts in speciation rates: one at their origin of Euisoptera and the other concordant with evolution of Termitidae. On the other hand, there was no obvious trend towards deceleration in speciation rates for termites as a whole, nor within the most species-rich families. The provided trees might represent a valuable resource for termite comparative studies by summarizing the available phylogenetic information, while accounting for uncertainty in the inferred topologies.

Lignocellulose comprises a significant portion of municipal solid waste (MSW) - 40-70% in developed countries, including paper, wood, and yard waste. Cellulose and hemicellulose are often shielded by lignin, posing a barrier to waste decomposition and landfill gas generation. Unfortunately, lignin is resistant to microbial degradation under low-oxygen conditions that normally occur in MSW landfills. The bacterium strain TAV5, microaerophilic and member of phylum Verrucomicrobia, isolated from the hindgut of the Reticulitermes flavipes termite, the most widely distributed subterranean termite in North America. Its genome contains genes associated with methylotrophic competency which code for enzymes that structurally modify lignin. The overall goal of this research was to use TAV5 to modify lignin and boost methane production from MSW. Batch-scale reactors (125 mL) were filled with paper, yard, or wood waste, and four ratios of mixed of waste. Reactors were seeded with different ratios of TAV5 to anaerobic digester (AD) microorganisms (representing landfill anaerobic microorganisms). Based on batch tests, optimal ratios of TAV5 to AD microorganisms were used to seed wastes (mixed, yard, and wood) in 6-gallon reactors. Addition of TAV5 increased methane production from mixed waste, yard waste, and wood, by 49%, 34%, and 297%, respectively. TAV5 decreased acid soluble lignin by 7-39%, depending on waste type. TAV5 grown under aerobic conditions and room temperature (not requiring a heated anaerobic chamber) was found to remain viable and increase methane production under low-level oxygen conditions (1-2%). This finding will potentially lessen costs for growing large volumes of it for seeding landfills.

Thermal modification of wood is a promising alternative to chemical and biocidal modification processes, increasing the biological durability and dimensional stability of wood. However, the wood-decay resistance properties of heat-treated wood are still not well known. The main objective of this study was to determine the biological resistance of heat-treated ash wood, and assess the antifungal and anti-termite activity of extractive compounds from heat-treated ash woods, depending on the intensity of the modification process (2 hours at 170, 200, 215, 228 (°C) - steam pressure). Untreated and heat-treated wood samples were extracted with water or acetone. The extracts were then used to determine inhibition effectiveness against white-rot (Trametes versicolor) and brown-rot (Rhodonia placenta) fungi. Whatman papers impregnated with extractives were used to evaluate the inhibition of termite feeding. Lastly, the extractives were analyzed by Gas Chromatography - Mass Spectrometry (GC-MS) and compared for their level of anti-termite and antifungal activity. The results showed that the degree of antifungal activity of these extracts depended on the solvent used during the extraction process and varied depending on heat treatment intensity. The extracts were more effective against brown-rot than white-rot fungi. However, the anti-termite activity of heat-treated ash wood extracts was not really significant. A GC-MS analysis showed that the main share of the extractives in untreated wood was removed. In addition, new chemical elements were generated by the thermal degradation of wood polymers (lignin and hemicelluloses), including aliphatic acids, monosaccharides and other products resulting from their dehydration reaction. The most abundant element was syringaldehyde, from lignin derived compounds, which might explain the antifungal activities of thermally treated ash wood extracts.

Lignocellulose comprises a significant portion of municipal solid waste (MSW) - 40-70% in developed countries, including paper, wood, and yard waste. Cellulose and hemicellulose are often shielded by lignin, posing a barrier to waste decomposition and landfill gas generation. Unfortunately, lignin is resistant to microbial degradation under low-oxygen conditions that normally occur in MSW landfills. The bacterium strain TAV5, microaerophilic and member of phylum Verrucomicrobia, isolated from the hindgut of the Reticulitermes flavipes termite, the most widely distributed subterranean termite in North America. Its genome contains genes associated with methylotrophic competency which code for enzymes that structurally modify lignin. The overall goal of this research was to use TAV5 to modify lignin and boost methane production from MSW. Batch-scale reactors (125 mL) were filled with paper, yard, or wood waste, and four ratios of mixed of waste. Reactors were seeded with different ratios of TAV5 to anaerobic digester (AD) microorganisms (representing landfill anaerobic microorganisms). Based on batch tests, optimal ratios of TAV5 to AD microorganisms were used to seed wastes (mixed, yard, and wood) in 6-gallon reactors. Addition of TAV5 increased methane production from mixed waste, yard waste, and wood, by 49%, 34%, and 297%, respectively. TAV5 decreased acid soluble lignin by 7-39%, depending on waste type. TAV5 grown under aerobic conditions and room temperature (not requiring a heated anaerobic chamber) was found to remain viable and increase methane production under low-level oxygen conditions (1-2%). This finding will potentially lessen costs for growing large volumes of it for seeding landfills.

Thermal modification of wood is a promising alternative to chemical and biocidal modification processes, increasing the biological durability and dimensional stability of wood. However, the wood-decay resistance properties of heat-treated wood are still not well known. The main objective of this study was to determine the biological resistance of heat-treated ash wood, and assess the antifungal and anti-termite activity of extractive compounds from heat-treated ash woods, depending on the intensity of the modification process (2 hours at 170, 200, 215, 228 (°C) - steam pressure). Untreated and heat-treated wood samples were extracted with water or acetone. The extracts were then used to determine inhibition effectiveness against white-rot (Trametes versicolor) and brown-rot (Rhodonia placenta) fungi. Whatman papers impregnated with extractives were used to evaluate the inhibition of termite feeding. Lastly, the extractives were analyzed by Gas Chromatography - Mass Spectrometry (GC-MS) and compared for their level of anti-termite and antifungal activity. The results showed that the degree of antifungal activity of these extracts depended on the solvent used during the extraction process and varied depending on heat treatment intensity. The extracts were more effective against brown-rot than white-rot fungi. However, the anti-termite activity of heat-treated ash wood extracts was not really significant. A GC-MS analysis showed that the main share of the extractives in untreated wood was removed. In addition, new chemical elements were generated by the thermal degradation of wood polymers (lignin and hemicelluloses), including aliphatic acids, monosaccharides and other products resulting from their dehydration reaction. The most abundant element was syringaldehyde, from lignin derived compounds, which might explain the antifungal activities of thermally treated ash wood extracts.

Background: Termites are among the most successful insect lineages on the globe and are responsible for providing numerous ecosystem services. They mainly feed on wood and other plant material at different stages of humification. Lignocellulose is often a principal component of such plant diet, and termites largely rely on their symbiotic microbiota and associated enzymes to decompose their food efficiently. While lower termites and their gut flagellates were given larger scientific attention in the past, the gut lignocellulolytic bacteria of higher termites remain less explored. Therefore, in this study, we investigated the structure and function of gut prokaryotic microbiomes from 11 higher termite genera representative of Syntermitinae, Apicotermitinae, Termitidae and Nasutitermitinae subfamilies, broadly grouped into plant fibre- and soil-feeding termite categories. Results: Despite the different compositional structures of the studied termite gut microbiomes, reflecting well the diet and host lineage, we observed a surprisingly high functional congruency between gut metatranscriptomes from both feeding groups. The abundance of transcripts encoding for carbohydrate active enzymes as well as expression and diversity profiles of assigned glycoside hydrolase families were also similar between plant fibre- and soil-feeding termites. Yet, dietary imprints highlighted subtle metabolic differences specific to each feeding category. Roughly, 0.18% of de novo re-constructed gene transcripts were shared between the different termite gut microbiomes, making each termite gut a unique reservoir of genes encoding for potentially industrially applicable enzymes, e.g. relevant to biomass degradation. Taken together, we demonstrated the functional equivalence in microbial populations across different termite hosts. Conclusions: Our results provide valuable insight into the bacterial component of the termite gut system and significantly expand the inventory of termite prokaryotic, SCOPUS: ar.j, info:eu-repo/semantics/published

With its unique consortium of microorganisms from all domains of life, termite gut is considered one of the most efficient lignocellulose degrading systems in nature. Recently, host diet and taxonomy as well as gut microenvironmental conditions have emerged as main factors shaping microbial communities in termite guts. The aim of this thesis was to investigate this highly efficient lignocellulolytic system at holobiont level, with a particular focus on gut microbiome function and composition in relation to the host diet. As a starting point, we optimised a complete framework for an accurate termite gut prokaryote-oriented metatranscriptomics, which was at the basis of all subsequent sequencing assay designs and analyses performed in the course of the work. Afterwards, we characterised the compositions and functions of biomass-degrading bacterial communities in guts of plant fibre- and soil-feeding higher termites, proving the existence of functional equivalence across microbial populations from different termite hosts. We also showed that each termite is a reservoir of unique microorganisms and their accompanying genes. We further extended above approach to metagenomics and bacterial genomes reconstruction and we applied it to explore the process of biomass digestion in the different sections of the highly compartmented gut of soil feeding Labiotermes labralis. We showed that primarily cellulolytic activity of the termite host was restricted to foregut and midgut, while bacterial contribution was most pronounced in P1 and P3 hindgut compartments and included activities targeting broad range of lignocellulose components. Finally, we investigated the adaptation of a laboratory-maintained grass-feeding higher termite colony of Cortaritermes spp. to Miscanthus diet at host and symbiont levels. A natural system of a termite gut was shown to progressively change in composition to yield a consortium of microbes specialised in degradation of a specific biomass. Overall, the, Doctorat en Sciences, info:eu-repo/semantics/nonPublished

The anatomy of the workers' digestive tube is essential in taxonomical studies of soil-feeding Apicotermitinae termites, especially in soldierless lineages. Two structures, the mesenteric-proctodeal junction and the enteric valve, have long been important to distinguish genera and species. By contrast, the gizzard (proventriculus) has been almost ignored by taxonomists because of its generally regressed state in soil-feeding termites. In this study, we document in detail for the first time the sclerotized structures and ornamentations in the gizzard in the Apicotermitinae subfamily. We identified two main clusters of species: those without ornamentations and those exhibiting a sclerotized pulvillar armature, which may include spicules or spines of diverse sizes, numbers and dispositions. The latter group comprises the majority of African soldierless species, a widely diverse and dominant group in tropical forests and savannas. We outline the potential role of the anatomy of the gizzard in the taxonomy of Apicotermitinae based on the interspecific anatomical variation of the pulvillar armatures. We suggest that sclerotized ornamentations regulate the flow of food particles and break or lacerate aggregates to facilitate the access of enzymes in the midgut., SCOPUS: ar.j, info:eu-repo/semantics/published

Phylogenetic relationships among subgroups of cockroaches and termites are still matters of debate. Their divergence times and major phenotypic transitions during evolution are also not yet settled. We addressed these points by combining the first nuclear phylogenomic study of termites and cockroaches with a thorough approach to divergence time analysis, identification of endosymbionts, and reconstruction of ancestral morphological traits and behaviour. Analyses of the phylogenetic relationships within Blattodea robustly confirm previously uncertain hypotheses such as the sister-group relationship between Blaberoidea and remaining Blattodea, and Lamproblatta being the closest relative to the social and wood-feeding Cryptocercus and termites. Consequently, we propose new names for various clades in Blattodea: Cryptocercus þ termites ¼ Tutricablattae; Lamproblattidae þ Tutricablattae ¼ Kittrickea; and Blattoidea þ Corydioidea ¼ Solumblattodea. Our inferred divergence times contradict previous studies by showing that most subgroups of Blattodea evolved in the Cretaceous, reducing the gap between molecular estimates of divergence times and the fossil record. On a phenotypic level, the blatto-dean ground-plan is for egg packages to be laid directly in a hole while other forms of oviposition, including ovovivipary and vivipary, arose later. Finally, other changes in egg care strategy may have allowed for the adaptation of nest building and other novelties.

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., SCOPUS: ar.j, info:eu-repo/semantics/published

Termites are important ecosystem engineers. Yet they are often difficult to identify due to the lack of reliable species-specific morphological traits for many species, which hampers ecological research. Recently, termitologists working with West African termites (West African Termite Taxonomy Initiative) convened for a workshop with the aim of beginning to address this problem. Repeated determination of the same termite samples by the most renowned taxonomists for West African termites identified the huge scale of the problem, as less than 10% of all species could be unambiguously determined to the species level. Intensive discussions and comparisons increased the identification success to around 25% at the end of the workshop. Yet many groups remained problematic and molecular markers and barcoding techniques combined with species delimitation approaches will be needed to help resolve these existing taxonomic problems. Based on the outcome of this workshop, we propose concerted initiatives to address termite taxonomy on a global scale. We are convinced that dedicated workshops on regional taxonomy that follow a similar structured approach, with repeated determination of the same sample, will help overcome the difficulties that termite taxonomy faces. This initiative can also serve as a blueprint for other taxonomical groups that are difficult to identify., SCOPUS: re.j, info:eu-repo/semantics/published

The traditional view of a lifelong monogamy between a king and a queen has recently been challenged in termites. In several species, multiple parthenogenetically-produced secondary queens replace the primary queen and mate with the primary king; this strategy is referred to as “Asexual Queen Succession” (AQS). The aim of my thesis was to investigate the modalities of reproduction and the ecology of neotropical soil-feeding termites from the Termitinae, with a focus on the inquiline termite Cavitermes tuberosus in the Termes group.In the first axis, we investigated the modalities of reproduction of C. tuberosus. (i) AQS is the main reproductive strategy of this species. (ii) The evolution of AQS requires the propensity of parthenogens to develop into neotenic queens. In C. tuberosus, secondary queens develop from a developmental stage of “aspirants” which participate to the social tasks usually undertaken by workers, as long as the primary queen is alive. (iii) In AQS species, a female-biased sex ratio is expected in the dispersing reproductives. In C. tuberosus, sex ratio varies among years and according to the type of reproductives, and the population sex ratio is balanced. These results raise hints on queen-king conflict over the sex ratio.In the second axis, we described the ecology and symbioses of C. tuberosus. (iv) Wolbachia, an endosymbiotic bacterium mainly known for manipulating the reproduction of arthropods in order to enhance its own transmission, infects all individuals in societies. This bacterium, particularly abundant in a gut-associated bacteriome, may play a role in the nutrition of C. tuberosus; both partners would have evolved a mutualistic symbiosis. (v) Inquiline termites live in a nest built by other termite species and do not forage outside. Physico-chemical measures and microbiota sequencing revealed that C. tuberosus is a generalist nest-feeder.Finally, we expanded our study of the breeding systems in the phylogenetic proximity of C. tubero, Doctorat en Sciences, info:eu-repo/semantics/nonPublished

Termites are the principal decomposers in tropical and subtropical ecosystems around the world. Time-calibrated molecular phylogenies show that some lineages of Neoisoptera diversified during the Oligocene and Miocene, and acquired their pantropical distribution through transoceanic dispersal events, probably by rafting in wood. In this paper, we intend to resolve the historical biogeography of one of the earliest branching lineages of Neoisoptera, the Rhinotermitinae. We used the mitochondrial genomes of 27 species of Rhinotermitinae to build two robust time-calibrated phylogenetic trees that we used to reconstruct the ancestral distribution of the group. Our analyses support the monophyly of Rhinotermitinae and all genera of Rhinotermitinae. Our molecular clock trees provided time estimations that diverged by up to 15.6 million years depending on whether or not 3rd codon positions were included. Rhinotermitinae arose 50.4–64.6 Ma (41.7–74.5 Ma 95% HPD). We detected four disjunctions among biogeographic realms, the earliest of which occurred 41.0–56.6 Ma (33.0–65.8 Ma 95% HPD), and the latest of which occurred 20.3–34.2 Ma (15.9–40.4 Ma 95% HPD). These results show that the Rhinotermitinae acquired their distribution through a combination of transoceanic dispersals and dispersals across land bridges., SCOPUS: ar.j, info:eu-repo/semantics/published

Some species of termites evolved an outstanding reproductive strategy called asexual queen succession (AQS), in which the primary queen is replaced by multiple parthenogenetically produced daughters (neotenics) that mate with the primary king. When the primary king is eventually replaced, this time by sexually produced neotenic king(s), sex-asymmetric inbreeding occurs and the queen’s genome is more transmitted than that of the king, thereby increasing the reproductive value of female dispersers, and female-biased population sex ratio is expected. Yet, the life cycle, the breeding system dynamics and AQS modalities differ between AQS species, thereby modifying the relative genetic contribution of primary reproductives in the colony and thus also the equilibrium sex ratio. We estimated colonial and population sex ratio over two consecutive dispersal periods in a French Guiana population of Cavitermes tuberosus (Termitinae) in which the founding queen may be replaced only after colony maturity, some neotenic females may be sexually produced, and some female dispersers arise through parthenogenesis. Colonial sex ratio varied among colonies: primary-headed nests with higher within-nest relatedness produced more females than neotenic-headed nests with lower relatedness among individuals. Over the two dispersal periods, the population investment sex ratio fluctuated around 1:1, thereby confirming that AQS breeding system is not necessarily linked with female-biased sex ratio. The balanced alate sex ratio, combined with the occurrence of sexually produced neotenic queens, is possibly the outcome of a queen-king conflict between the primary reproductives., SCOPUS: ar.j, info:eu-repo/semantics/published

Termitidae comprises ∼80% of all termite species [1] that play dominant decomposer roles in tropical ecosystems [2, 3]. Two major events during termite evolution were the loss of cellulolytic gut protozoans in the ancestor of Termitidae and the subsequent gain in the termitid subfamily Macrotermitinae of fungal symbionts cultivated externally in “combs” constructed within the nest [4, 5]. How these symbiotic transitions occurred remains unresolved. Phylogenetic analyses of mitochondrial data previously suggested that Macrotermitinae is the earliest branching termitid lineage, followed soon after by Sphaerotermitinae [6], which cultivates bacterial symbionts on combs inside its nests [7]. This has led to the hypothesis that comb building was an important evolutionary step in the loss of gut protozoa in ancestral termitids [8]. We sequenced genomes and transcriptomes of 55 termite species and reconstructed phylogenetic trees from up to 4,065 orthologous genes of 68 species. We found strong support for a novel sister-group relationship between the bacterial comb-building Sphaerotermitinae and fungus comb-building Macrotermitinae. This key finding indicates that comb building is a derived trait within Termitidae and that the creation of a comb-like “external rumen” involving bacteria or fungi may not have driven the loss of protozoa from ancestral termitids, as previously hypothesized. Instead, associations with gut prokaryotic symbionts, combined with dietary shifts from wood to other plant-based substrates, may have played a more important role in this symbiotic transition. Our phylogenetic tree provides a platform for future studies of comparative termite evolution and the evolution of symbiosis in this taxon., SCOPUS: ar.j, info:eu-repo/semantics/published

Dispersal of soil-dwelling organisms via the repeatedly exposed Sunda shelf through much of the Pleistocene in Southeast Asia has not been studied extensively, especially for invertebrates. Here we investigated the phylogeography of an endemic termite species, Macrotermes gilvus (Hagen), to elucidate the spatiotemporal dynamics of dispersal routes of terrestrial fauna in Pleistocene Southeast Asia. We sampled 213 termite colonies from 66 localities throughout the region. Independently inherited microsatellites and mtDNA markers were used to infer the phylogeographic framework of M. gilvus. Discrete phylogeographic analysis and molecular dating based on fossil calibration were used to infer the dynamics of M. gilvus dispersal in time and space across Southeast Asia. We found that the termite dispersal events were consistently dated within the Pleistocene time frame. The dispersal pattern was multidirectional, radiating eastwards and southwards out of Indochina, which was identified as the origin for dispersal events. We found no direct dispersal events between Sumatra and Borneo despite the presence of a terrestrial connection between them during the Pleistocene. Instead, central Java served as an important link allowing termite colonies to be established in Borneo and Sumatra. Our findings support the hypothesis of a north-south dispersal corridor in Southeast Asia and suggest the presence of alternative dispersal routes across Sundaland during the Pleistocene. For the first time, we also propose that a west-east dispersal through over-water rafting likely occurred across the Pleistocene South China Sea. We found at least two independent entry routes for terrestrial species to infiltrate Sumatra and Borneo at different times.

Clonal eucalyptus are highly valued in Morocco and in the Mediterranean basin for the production of industrial wood, but nothing is known about their ability to resist xylophagous plants. This study aims to investigate the chemical defenses response of eucalyptus trees to artificially attacks by young larvae of Phoracantha recurva by assessing changes in essential oil production and composition of leaves from Eucalyptus grandis and its clone 977. Fungicidal and termicidal essential oil activities were evaluated to value their biocidal properties. In the Northwest region of Morocco, six of vigorous eucalyptus-trees were selected for each wood species studied. In contrast to a control tree without infection, three from each species were artificially infested in three part of the trunk by hatched larvae of P. recurva. After two months, the most important cambial reaction was observed with E. grandis compared to clone 977. For both species, the primary reaction is less important compared to the reaction of deep tissues. The essential oils recovered by hydrodistillation show that the infested trees have the highest average yield. Arian parties are 1.51% and 2.36% respectively for E. grandis and its clone 977, after infestation, we can observe a decrease of the production of essential in the leaves, respectively 1% and 1.5% for E. grandis and its clone 977. The analysis of the chemical composition by GC-MS method of essential oils shows that the leaves of infested trees of E. grandis and its clone 977, have specific constituents resulting from infestation such as Endo-fenchol, trans-carveol, Nerol and Spathulenol. Equally, this analysis revealed that the attacked trees hemi-synthesized more components compared to their controls. However, the evaluation of fungicidal and termiticidal activities showed that the essentials oil of the clone 977 is more active compared to the parental species E. grandis.

Dispersal of soil-dwelling organisms via the repeatedly exposed Sunda shelf through much of the Pleistocene in Southeast Asia has not been studied extensively, especially for invertebrates. Here we investigated the phylogeography of an endemic termite species, Macrotermes gilvus (Hagen), to elucidate the spatiotemporal dynamics of dispersal routes of terrestrial fauna in Pleistocene Southeast Asia. We sampled 213 termite colonies from 66 localities throughout the region. Independently inherited microsatellites and mtDNA markers were used to infer the phylogeographic framework of M. gilvus. Discrete phylogeographic analysis and molecular dating based on fossil calibration were used to infer the dynamics of M. gilvus dispersal in time and space across Southeast Asia. We found that the termite dispersal events were consistently dated within the Pleistocene time frame. The dispersal pattern was multidirectional, radiating eastwards and southwards out of Indochina, which was identified as the origin for dispersal events. We found no direct dispersal events between Sumatra and Borneo despite the presence of a terrestrial connection between them during the Pleistocene. Instead, central Java served as an important link allowing termite colonies to be established in Borneo and Sumatra. Our findings support the hypothesis of a north-south dispersal corridor in Southeast Asia and suggest the presence of alternative dispersal routes across Sundaland during the Pleistocene. For the first time, we also propose that a west-east dispersal through over-water rafting likely occurred across the Pleistocene South China Sea. We found at least two independent entry routes for terrestrial species to infiltrate Sumatra and Borneo at different times.

Clonal eucalyptus are highly valued in Morocco and in the Mediterranean basin for the production of industrial wood, but nothing is known about their ability to resist xylophagous plants. This study aims to investigate the chemical defenses response of eucalyptus trees to artificially attacks by young larvae of Phoracantha recurva by assessing changes in essential oil production and composition of leaves from Eucalyptus grandis and its clone 977. Fungicidal and termicidal essential oil activities were evaluated to value their biocidal properties. In the Northwest region of Morocco, six of vigorous eucalyptus-trees were selected for each wood species studied. In contrast to a control tree without infection, three from each species were artificially infested in three part of the trunk by hatched larvae of P. recurva. After two months, the most important cambial reaction was observed with E. grandis compared to clone 977. For both species, the primary reaction is less important compared to the reaction of deep tissues. The essential oils recovered by hydrodistillation show that the infested trees have the highest average yield. Arian parties are 1.51% and 2.36% respectively for E. grandis and its clone 977, after infestation, we can observe a decrease of the production of essential in the leaves, respectively 1% and 1.5% for E. grandis and its clone 977. The analysis of the chemical composition by GC-MS method of essential oils shows that the leaves of infested trees of E. grandis and its clone 977, have specific constituents resulting from infestation such as Endo-fenchol, trans-carveol, Nerol and Spathulenol. Equally, this analysis revealed that the attacked trees hemi-synthesized more components compared to their controls. However, the evaluation of fungicidal and termiticidal activities showed that the essentials oil of the clone 977 is more active compared to the parental species E. grandis.

Deadwood is an important legacy structure in managed forests, providing continuity in shelter and resource availability for many organisms and acting as a vehicle by which nutrients can be passed from one stand to the next following a harvest. Despite existing at the interface between below- and above-ground systems, however, much remains unknown about the role woody debris plays in linking these zones. Moreover, it remains untested whether the accelerative effects of wood-feeding insects on wood decomposition influence tree growth or nutritional status in forests. In this study, we added different quantities of pine logs to the bases of saplings in two-year-old loblolly pine (Pinus taeda L.) plantations in Mississippi, USA. We included a treatment in which subterranean termites (Blattodea: Rhinotermitidae: Reticulitermes) were excluded from logs to determine how these insects affect the release of nutrients from wood and, in turn, tree growth. After 51 months of decomposition, we quantified below-ground effects by measuring microbial biomass, plant-available forms of N, and ectomycorrhizal diversity associated with fine tree roots. Meanwhile, above-ground measurements focused on the elemental concentrations in decomposing wood either protected or unprotected from termites and tree metrics related to growth and nutrient status. We found additions of wood to significantly increase nitrate and potential net nitrification relative to reference treatments but detected no significant effects on tree growth, needle nitrogen concentrations, or ectomycorrhizal diversity. Soil nitrate and potential net nitrification were higher under protected vs. unprotected logs, and plant-available forms of N were mostly more abundant short distances away from both protected and unprotected logs than directly under them. The wood of logs protected from termites had significantly lower concentrations of most elements compared to that of unprotected logs, largely due to the large amounts of

Termite soldiers often combine mechanical adaptations with defensive chemicals secreted from the frontal gland. Amongst the most remarkable strategies for mechanical defence, symmetrical and asymmetrical snapping mandibles evolved in several lineages of the diversified subfamily Termitinae (Termitidae). The contribution of the frontal chemical weapon to defence in snapping soldiers has long been doubted and the subfamily Termitinae overlooked with respect to soldier-produced chemicals. We recently reported an active frontal gland secreting unique defensive chemicals in the symmetrically snapping soldiers of Cavitermes tuberosus. The aim of the present study was a larger-scale comparison of chemical defence in symmetrically snapping soldiers. We studied the anatomy of the frontal gland and the chemistry of its secretion in five additional Neotropical species and mapped our observations on a de novo constructed molecular phylogeny of the target group. We show that the soldiers of all studied species possess a functional frontal gland, housed in part in the frontal projections on their heads. Phylogenetic reconstruction groups the studied taxa into two well-defined clades, supported by fundamental differences in defensive chemicals, either arising exclusively from the lipogenic pathway or containing also the products of the isoprenoid pathway. Our results also identify a new genus of symmetrical snappers, related to the genus Cavitermes, incorrectly classified in several previous studies., SCOPUS: ar.j, info:eu-repo/semantics/published

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 R, SCOPUS: ar.j, info:eu-repo/semantics/published

Termites are major decomposers in tropical regions and play critical roles in many soil-related processes. Studies conducted in Asia and the Neotropics suggest that habitat modification can strongly affect termite assemblages, but data on termite communities from forests in Africa, especially West Africa, are scarce. Here, we measured the short-term impact of slash-and-burn agriculture on termite assemblages in an agricultural region of central Côte d'Ivoire. We assessed termite diversity and relative abundance in four habitat types: secondary forest, cleared forest, burned forest, and crop fields. The secondary forest had higher species richness compared with the other habitats, but all habitat types had similar assemblage structures. Fungus-growing termites were the most abundant feeding group in all habitats. Soil feeders were most abundant in secondary forest, intermediately abundant in cleared and burned forests, and almost entirely absent in crop fields. Wood-feeding species showed clear responses to burning; their abundances decreased after fire. We conclude that slash-and-burn agriculture does not appear to severely erode the diversity of termite assemblages. This could be due to the dominance of ecologically versatile fungus growers or to the relatively long time between clearing and burning. However, forest clearing negatively affects soil feeders, with the Apicotermitinae most affected by canopy loss., SCOPUS: ar.j, info:eu-repo/semantics/published