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Intrinsic dinitrogen (N2) fixation by diazotrophic bacteria in termite hindguts has been considered an important pathway for nitrogen acquisition in termites. However, studies that supported this claim focused on measuring instant N2 fixation rates and failed to address their relationship with termite colony growth and reproduction over time. We here argue that not all wood-feeding termites rely on symbiotic diazotrophic bacteria for colony growth. The present study looks at dietary nitrogen acquisition in a subterranean termite (Rhinotermitidae, Coptotermes). Young termite colonies reared with wood and nitrogen-rich organic soil developed faster, compared to those reared on wood and inorganic sand. More critically, further colony development was arrested if access to organic soil was removed. In addition, no difference of relative nitrogenase expression rates was found when comparing the hindguts of termites reared between the two conditions. We therefore propose that subterranean termite (Rhinotermitidae) colony growth is no longer restricted to metabolically expensive intrinsic N2 fixation, as the relationship between diazotrophic bacteria and subterranean termites may primarily be trophic rather than symbiotic. Such reliance of Rhinotermitidae on soil microbial decomposition activity for optimal colony growth may also have had a critical mechanistic role in the initial emergence of Termitidae.

Several species of drywood termites, subterranean termites, and fungus-growing termites cause extensive economic losses annually worldwide. Because no universal method is available for controlling all termites, correct species identification is crucial for termite management. Despite deep neural network technologies’ promising performance in pest recognition, a method for automatic termite recognition remains lacking. To develop an automated deep learning classifier for termite image recognition suitable for mobile applications, we used smartphones to acquire 18,000 original images each of four termite pest species: Kalotermitidae: Cryptotermes domesticus (Haviland); Rhinotermitidae: Coptotermes formosanus Shiraki and Reticulitermes flaviceps (Oshima); and Termitidae: Odontotermes formosanus (Shiraki). Each original image included multiple individuals, and we applied five image segmentation techniques for capturing individual termites. We used 24,000 individual-termite images (4 species × 2 castes × 3 groups × 1,000 images) for model development and testing. We implemented a termite classification system by using a deep learning–based model, MobileNetV2. Our models achieved high accuracy scores of 0.947, 0.946, and 0.929 for identifying soldiers, workers, and both castes, respectively, which is not significantly different from human expert performance. We further applied image augmentation techniques, including geometrical transformations and intensity transformations, to individual-termite images. The results revealed that the same classification accuracy can be achieved by using 1,000 augmented images derived from only 200 individual-termite images, thus facilitating further model development on the basis of many fewer original images. Our image-based identification system can enable the selection of termite control tools for pest management professionals or homeowners.

A total of 10 bacterial isolates have been isolated from the gut of termites (Isoptera: Rhinotermitidae and Termitidae) and are known to have the ability to produce lignocellulolytic enzymes consisting of cellulase, laccase, and lignin peroxidase. The enzymatic ability allows these bacteria to be used as a source of new enzymes in the industrial world. However, further research on the character of bacteria to support identification has not been carried out. This study aims to characterize lignocellulolytic bacteria in the gut of termites morphologically and biochemically. Morphological observations were carried out including colony shape, colony edge, colony color, growth type, bacterial cell shape, and gram staining. Meanwhile, the biochemical characterization carried out included glucose fermentation test, indole formation, starch hydrolysis, catalase test, and nitrate reduction. The results showed that ten isolates of lignocellulolytic bacteria from the gut of termites (Isoptera: Rhinotermitidae and Termitidae) grew facultatively anaerobic, had almost similar morphological characters, with colony shapes including irregular and filamentous, colony edges in the form of lobate, undulate, and filamentous, and coloration. Colonies are white to yellowish white. The result of gram staining showed that most of the bacteria were gram positive bacteria with coccus and bacillus shaped bacterial cells. Biochemical analysis showed that these bacteria have the ability to ferment glucose, hydrolyze starch, reduce hydrogen peroxide (Hâ‚‚Oâ‚‚ 30%) and reduce nitrate.ÂÂ

The subterranean termite Reticulitermes chinensis Snyder is an important pest in China. We determined the inhibition of six selected insecticides to acetylcholinesterase (AChE) extracted from R. chinensis. Our results yielded half maximal inhibitory concentrations (I50) for each of the insecticides to be 3.49 × 10–3 M for methomyl, 3.87 × 10–2 M for phoxim, 2.18 × 10–3 M for triazophos, 1.89 × 10–3 M for profenosos, 1.10 × 10–3 M for malathion, and 4.39 × 10–2 M for omethoate. Furthermore, the inhibitory activity of AChE by the six insecticides was increased with the increase of insecticide concentration from 3.3 × 10–7 to 5 × 10–3 M. These results provide a theoretical basis for the management of R. chinensis.

Rhinotermitidae (Isoptera) is an economically important termite family globally. The family is not monophyletic, and the relationships among some of its taxa remain confusing. The taxonomic status of some subfamilies is likely questionable because of various morphological characters of the soldiers and imagoes. Twenty species in 10 genera, representing all six subfamilies of Rhinotermitidae were studied herein. Morphological phylogenetic trees based on 65 characters and molecular phylogenetic trees based on mitochondrial COII and 16SrRNA genes were reconstructed. The sequence composition and genetic distance were analyzed. Based on these results, Rhinotermitidae is polyphyletic. In the morphological trees, the family was divided into five clades. Heterotermitinae and Coptotermitinae were grouped into the most apical one of them and constituted the sister group to Termitidae in the Bayesian inference (BI) tree. In the combined molecular tree, Rhinotermitidae was divided into three clades. The position of the clade composing Heterotermitinae and Coptotermitinae was the same as in the morphological BI tree. The nucleotide sequence analyses also showed that the genetic distances between Heterotermitinae or Coptotermitinae with Termitidae might be closer than those between Heterotermitinae or Coptotermitinae with other subfamilies in Rhinotermitidae. It is postulated that the relationship of Heterotermitinae and Coptotermitinae with other subfamilies of Rhinotermitidae is not as close as that indicated in the current taxonomic system. They might be the real representative of the intermediate lineage from lower to higher termites. These findings further suggest that Heterotermitinae and Coptotermitinae should be separated from Rhinotermitidae and be upgraded as a whole to family rank.

Deciphering the timing and tempo of lineage diversification of organisms has greatly benefited from advances in Bayesian phylogenetic analyses using morphological data. Those advances, however, have not been used for termites despite a rich fossil record. Here, we estimate divergence times for living and fossil termites using the fossilized birth–death (FBD) process on a previously published morphological matrix expanded with two new fossils that we describe (see Appendices 1 & 2). Those fossils, based on soldier specimens, are the ‘mid’-Cretaceous mastotermitid Milesitermesengeligen. et sp. nov., and the Middle Eocene Reticulitermesgrimaldiisp. nov. The latter is the oldest occurrence of a Rhinotermitidae soldier and the first termite soldier described from Baltic amber. Our dating estimates provide new stem- and crown-ages for termites, suggesting older ages than previously thought for several lineages. Importantly, crown-Isoptera—and therefore eusociality—may have arisen ~200 Ma. We conclude with further directions to keep improving our understanding of the timing of differentiation in termites.Page 2 of 77Systematic Entomology

In the eastern United States, there are nine species of subterranean termites in three genera: Reticulitermes (six species), Coptotermes (two species), and Prorhinotermes (one species). These species serve as important ecological players by decomposing cellulose material, and some are important structural pests. Many of these species are difficult to discriminate morphologically and require examining the reproductive or soldier castes, which can be difficult to collect. While some genetic tools have been developed for species identification, they are often expensive and time-consuming. To help facilitate identification, we developed a more cost-effective and rapid genetic method to identify Reticulitermes species by screening 10 PCR primers that amplified inter-simple sequence repeats (ISSRs) in other termite species. From these, one primer was amplified in all five focal Reticulitermes species and contained conserved, species-specific fragments. We further screened this identification method on samples of each species covering a diversity of mitochondrial DNA haplotypes and localities. This identification method utilizing ISSRs can be used to quickly identify five species of Reticulitermes subterranean termites in the eastern United States in a matter of hours, providing a useful technique for pest management as well as future ecological research.

The subterranean termite Reticulitermes aculabialis was firstly described from the soldier caste in 1977 and diagnose from the imago has been difficult due to the lack of description of alate. In this paper, a detailed description of alate for R. aculabialis is presented, including additional data to soldiers. The data are chiefly based on the external morphology of R. aculabialis imago, which has never been described before. All the samples of alates and soldiers were collected in Xi’an, Shaanxi province, China. All of the essential specific characteristics are illustrated for identification purposes.

Termites are intimately tied to the microbial world, as they utilize their gut microbiome for the conversion of plant cellulose into necessary nutrients. Subterranean termites must also protect themselves from the vast diversity of harmful microbes found in soil. However, not all soil microbes are harmful, such as Streptomyces and methanotrophic bacteria that some species of termites harbor in complex nest structures made of fecal material. The eastern subterranean termite, Reticulitermes flavipes, has a simple nest structure consisting of fecal lined galleries. We tested the hypothesis that R. flavipes maintains a select microbial community in its nests to limit the penetration of harmful soilborne pathogens and favor the growth of beneficial microbes. Using Illumina sequencing, we characterized the bacterial and fungal communities in the surrounding soil, in the nest galleries, and on the cuticle of workers. We found that the galleries provide a more beneficial microbial community than the surrounding soil. Bacterial and fungal diversity was highest in the soil, lower in the galleries, and least on the cuticle. Bacterial communities clustered together according to the substrate from which they were sampled, but this clustering was less clear in fungal communities. Most of the identified bacterial and fungal taxa were unique to one substrate, but the soil and gallery communities had very similar phylum-level taxonomic profiles. Notably, the galleries of R. flavipes also harbored both the potentially beneficial Streptomyces and the methanotrophic Methylacidiphilales, indicating that these microbial associations in fecal material pre-date the emergence of complex fecal nest structures. Surprisingly, several pathogenic groups were relatively abundant in the galleries and on the cuticle, suggesting that pathogens may accumulate within termite nests over time while putatively remaining at enzootic level during the lifetime of the colony.

Termites are a significant pest of buildings, agriculture, and trees, and are mainly controlled by baiting. However, baiting systems are available for only lower termites (Rhinotermitidae) not for higher termites (Termitidae). Termite foraging behavior associated with baiting systems varies among species and families, and plays a significant role in baiting success. Here, foraging behavior ofOdontotermes obesus(Blattodea: Termitidae: Macrotermitinae), a fungus-growing higher termite, was investigated relative to three bait-station sizes (small, medium, and large) containing different quantities of food. Significantly more workers recruited to large stations (470/station) compared to medium (246/station) and small (124/station) stations. Abundance ofO. obesusin large and medium stations significantly positively correlated with relative humidity whereas negative but non-significant correlations were observed with temperature in large and medium stations. Total and continuous contacts with the stations increased with time and were greater in large stations. Station abandonment due to disturbance was significantly less in large stations (3%) followed by medium (9%) and small stations (20%). Our results suggest that large stations (≈8 litres volume) work best for population management ofO. obesusand other related fungus-growing higher termites.

Made available in DSpace on 2021-06-25T11:08:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-04-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Termites are well recognized by their complex development trajectories, involving dynamic differentiation process between non-reproductive castes, workers and soldiers. These insects are associated with endosymbiotic microorganisms, which help in lignocellulose digestion and nitrogen metabolism. Aiming to identify genes harbouring biotechnological potential, we analyzed workers and soldiers RNA-Seq data of three neotropical termites: Heterotermes tenuis (Isoptera: Rhinotermitidae), Velocitermes heteropterus (Isoptera: Termitidae) and Cornitermes cumulans (Isoptera: Termitidae). We observed differences in the microbiota associated with each termite family, and found protists' genes in both Termitidae species. We found an opposite pattern of caste-biased gene expression between H. tenuis and the termitids studied. Moreover, the two termitids are considerably different concerning the number of differentially expressed genes (DEGs). Functional annotation indicated considerable differences in caste-biased gene content between V. heteropterus and C. cumulans, even though they share similar diet and biological niche. Among the most DEGs, we highlighted those involved in caste differentiation and cellulose digestion, which are attractive targets for studying more efficient technologies for termite control, biomass digestion and other biotechnological applications. Departamento de Genética e Evolução Centro de Ciências Biológicas e da Saúde Universidade Federal de São Carlos Departamento de Genética Evolução Microbiologia e Imunologia Instituto de Biologia Universidade Estadual de Campinas Laboratório de Cupins Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) campus de Rio Claro Laboratório de Cupins Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP) campus de Rio Claro CNPq: CNPq: 139192/2015-8 CAPES: DS-CAPES 88882.426720/2019-01 CAPES: DS-CAPES 88882.426727/2019-01 CAPES: Finance Code 001 CNPq: PIBIC: 2743

Several termite species are significant economic pests, causing damage to wood in both man-made structures and also in forest ecosystem. The species belongs to genus Coptotermes (Rhinotermitidae: Isoptera: Blattodea) are widespread and few of them are among the world’s most dangerous wood pests. Two species of Coptotermes were collected, identified and described from yemene, mora and tali logs imported from Columbia, Suriname and Equitorial Guinea. These two intercepted species are non-native to India which are Coptotermes testaceus (Linnaeus) and Coptotermes sjostedti Holmgren. Identification was initially made with morphological characters and then with molecular DNA barcoding for a 348 bp fragment of 16S rRNA gene. Maximum likelihood Phylogenetic analysis results showed that data recovered as monophyletic which confirms the species identity. Coptotermes testaceus and C. sjostedti are in single clade. Coptotermes testaceus is neotropical in origin and C. sjostedti is native to Africa. Both the species are known to be serious pests in human habitats and forest ecosystem in the regions of their distributions. This first interception suggests possible chances of entry and establishment in India and provides an important alert for authorities concerned to take the necessary steps in monitoring and preventing its possible introduction. The importance of quarantine and potential infliction of damage they may cause if unnoticed and future measures to be taken are discussed.

The Neotropical family Serritermitidae is a monophyletic group of termites including two genera, Serritermes and Glossotermes, with different way-of-life, the former being the sole obligatory inquiline among “lower” termites, while the latter is a single-site nester feeding on dry rotten red wood. Like the most advanced termite’s family, the Termitidae, the Serritermitidae is an inner group of the paraphyletic family “Rhinotermitidae”, but unlike the Termitidae, it has been poorly studied so far. In this study, we bring new insights into the chemical ecology of this key taxon. We studied the trail-following pheromone of Serritermes serrifer and we identified (10Z,13Z)-nonadeca-10,13-dien-2-one as the only component of the trail-following pheromone of this termite species, as it is the case in Glossotermes, the other genus belonging to Serritermitidae. This result makes the family Serritermitidae clearly distinct from other Rhinotermitidae, such as the termites Psammotermes and Prorhinotermes, that use (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol and/or neocembrene as trail-following pheromones.

In social insects, the reproductive division of labor is often regulated through communication using cuticular hydrocarbons (CHCs) that indicate caste identity and reproductive status. In many termites, workers retain reproductive potential and can differentiate into ergatoid reproductives, and this process is mediated by the presence of reproductives in sex- and age-specific patterns. However, little is known about the variation of CHCs profiles during this transition. In this study, we analyzed the CHC profiles of workers in comparison with ergatoids of different age, sex, and mating status in the eastern subterranean termite, Reticulitermes flavipes (Kollar) (Blattodea: Rhinotermitidae), one of the most widely distributed termite species in the world. Both female and male ergatoids were characterized by the presence of tricosane and a group of long-chain and methyl-branched hydrocarbons (chain length ≥ 33), which were found in significantly lower quantities from workers. In addition, CHC profiles differed between newly differentiated (3–4 d) and old (20–25 d) ergatoids, but no difference in CHC signatures was found between females and males based on identified compounds. Heneicosane, a previously reported royal recognition pheromone in R. flavipes, was not detected in ergatoids examined in this study. The results of caste- and age-dependent variations suggest that CHCs may act as releaser pheromones that mediate caste recognition and age-related interactions between reproductives, but analytical results of identified compounds in this study do not support CHCs as sex-specific primer pheromones that regulate nestmate fertility. Royal pheromones in termites may involve complex hydrocarbon blends and non-hydrocarbon substances that await further investigation.

RESUMEN El termes subterraneo, Coptotermes havilandi Holmgren, se registra de un sitio previamente no documentado localizado en Manzanillo, Colima, Mexico. Es el primer registro de esta especie exotica en la costa oeste de America del Norte. Esta especie fue encontrada danando tablas nuevas de pino almacenadas en una bodega fiscal del puerto de Manzanillo. Su proximidad al puerto, asi como la falta de infestaciones en los alrededores, sugiere que muy probablemente fue introducida por via maritima. Tambien se incluyen nuevos registros de distribucion en la Ciudad de Mexico, D.F. (Mexico) y para el estado de Para (Brasil). Este trabajo muestra que la especie continua siendo introducida por el hombre a muchos paises a pesar de las cuarentenas establecidas. Palabras Clave: Coptotermes havilandi, distribucion geografica, primer registro, Mexico.

Oceanic rafting through driftwood has been hypothesized to be a mechanism underlying the transoceanic distribution of termites (Order: Blattodea). To test this hypothesis, we examined the salinity tolerance of 12 termite species from eight genera and three families, namely Archotermopsidae, Kalotermitidae, and Rhinotermitidae. Our results revealed that the survival rates of Incisitermes inamurai (Oshima), Cryptotermes domesticus (Haviland), Prorhinotermes flavus (Bugnion and Popoff), P. simplex (Hagen), and Heterotermes sp. are not affected by treatment with 3.5% saline water, strongly supported that oceanic rafting may be a mechanism underlying the insects' transoceanic distribution. By contrast, Hodotermopsis sjostedti Holmgren, Glyptotermes satsumensis (Matsumura), Coptotermes formosanus Shiraki, Co. gestroi (Wasmann), Reticulitermes virginicus (Banks), R. leptomandibularis Hsia and Fan, and R. kanmonensis Takematsu treated with saline water showed dehydration symptoms, and their mortality rates increased significantly within 12 days after treatment. These results indicate that these species are less likely to be dispersed through oceanic driftwood and that their transoceanic dispersal is rather more likely to occur through human transportation or land bridges. Phylogenetic positions and habitats of salinity‐tolerant termites implied that the acquisition of salinity tolerance may relate to both phylogeny and coastal living.

The subterranean termite, Psammotermes hypostoma Desneux (Isoptera: Rhinotermitidae)is considered one of the most dangerous termites in urban, rural and agricultural areas in the desert belt of Assiut governorate, Egypt. Organophosphate insecticides such as chlorpyrifos have been recommended to control subterranean termites in Egypt. The present research was conducted to evaluate the toxicity, persistency and effectiveness of chlorpyrifos (chlorzan 48% EC), imidacloprid (imidammex 70% WG), chlorantraniliprole (coragen 20% SC), indoxacarb (avaunt 15% EC) and spinosad (tracer 24% SC) against subterranean termites. The toxicity of these insecticides was tested against field strain of the subterranean termites using the cardboard dip-bioassay technique under laboratory conditions. The toxicity index after 12 and 24 hr exposure showed that chlorpyrifos has the highest termiticidal activity, with LC50s 1.19 and 0.13 ppm, followed by imidacloprid with LC50s 3.24 and 0.61 ppm, while spinosad was the least toxic one with LC50s.9.96 and 4.95 ppm. Furthermore, chlorpyrifos, imidacloprid and chlorantraniliprole registered significantly high percent reduction of the infested rural homes by subterranean termite, P. hypostoma, while indoxacarb and spinosad recorded the lowest reduction percentage after 30, 60, 90 and 120 days of treatment. In addition, the efficiency and residual effects of chlorpyrifos persisted up to 120 days followed by imidacloprid and chlorantraniliprole after treatment. Results of this study indicated that, chlorpyrifos exhibited the most powerful pesticide among all the insecticides tested, and imidacloprid and chlorantraniliprole were highly effective and it is given as unique and hopeful trends against subterranean termites under field conditions.

Social insects produce complex nest structures as a result of the repetition of simple behaviors by many individuals. Individual actions are often consistent across different socio-environmental conditions, which enables colonies to build a variety of structures with minimal change in behavior. In this study, we show that the individual building behavior of termites can be a species-specific trait shared even between distinct morphological castes. Subterranean termites engage in soil excavation in two different contexts in their life history: foraging for resources by workers and initial nest excavation by colony foundation pairs. Our comparison of tunneling behaviors by colony founders of three different species revealed distinct transporting mechanisms; Heterotermes aureus (Snyder) (Isoptera: Rhinotermitidae) and Gnathamitermes perplexus (Banks) (Isoptera: Termitidae) carry sand particles using only their mandibles, while Paraneotermes simplicicornis (Banks) (Isoptera: Kalotermitidae) use their legs to kick sand particles backward. The observed behaviors are consistent with those of workers in each species, despite a substantial dimorphism of body size, especially in G. perplexus. Furthermore, the behavioral difference is associated with distinct tunnel development and task allocation patterns among species. Our study suggests that the nest building behavior of termites varies little with context or function within a species but can change among species, emphasizing the fruitfulness of comparative studies in future research.

African termites are classified into five distinct families, Termitidae, Rhinotermitidae, Hodotermitidae, Termopsidae and Kalotermitidae. Termites are undoubtedly one of the key ecosystem engineers...

Congeneric species that live in sympatry may have evolved various mechanisms that maintain reproductive isolation among species. However, with the spread of invasive organisms owing to increased global human activity, some species that evolved in allopatry can now be found outside their native range and may have the opportunity to interact, in the absence of mechanisms for reproductive isolation. In South Florida, where the Asian subterranean termite, Coptotermes gestroi (Wamann), and the Formosan subterranean termite, Coptotermes formosanus Shiraki (Blattodea: Rhinotermitidae) are invasive, the two species can engage in heterospecific mating behavior as their distribution range and their dispersal flight season both overlap. Termites rely on semiochemicals for many of their activities, including finding a mate after a dispersal flight. In this study, we showed that females of both species produce (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol (DTE) from their tergal glands as a shared sex pheromone. We suggest that both species primarily rely on an inundative dispersal flight strategy to find a mate, and that DTE is used as a short distance pheromone or contact pheromone to initiate and maintain the tandem between males and females. The preference of C. gestroi males for C. formosanus females during tandem resulted from the relatively high amount of DTE produced by tergal glands of C. formosanus females, when compared with those of C. gestroi females. This results in confusion of mating in the field during simultaneous dispersal flights, with a potential for hybridization. Such observations imply that no prezygotic barriers emerged while the two species evolved in allopatry for ~18 Ma.

Subterranean termites are an ancient group of social insects, broadly spread, known primarily as economically important pests for the destruction of wooden structures and also as agricultural pests. Many of the banned chlorinated hydrocarbon insecticides used to be recommended for the control of termites. Hence, it has become necessary to find alternative measures for termite control in the natural diverse habitats as well as in the cultivated soil to diminish use of these chemicals. Therefore, in the present study, 4 strains of entomopathogenic nematodes (EPN) belong to the genus Steinernema were assessed against Coptotermes heimi (Wasmann). These EPN included Steinernema pakistanense NNRC-AS.04, S. siamkayai NNRC-As.12, S. bifurcatum NNRC-As.65, and S. maqbooli NNRC-As.88. Virulence of all strains was determined at 3 different EPN inocula in plastic containers layered with sand. A significant nematode inoculum effect was detected for all the tested EPN species. NNRC-AS.04 and NNRC-As.65 showed the highest virulence effects of 95 and 100%, respectively at 150 IJs/ml.

Termite colony size can influence its foraging activity, reproductive maturity, and, for pest species, potential for structural damage. Estimating colony size of subterranean termite species in field conditions has been challenging owing to their extensive foraging territory and their cryptic nesting habit and has primarily relied on mark–recapture methods. With laboratory-reared colonies in individual containers, determining colony size can be achieved by processing all termites from the nest material, which can be labor intensive and partially destructive. However, with the recent rise in the need of large laboratory colonies for use in colony-wide experimental protocols, there was an imperative to develop a procedure to estimate initial colony sizes without imposing a major stress on colonies before an experiment. In this study, the average daily wood consumption of whole colonies was used to infer the colony size of two Coptotermes, Wasmann (Blattodea: Rhinotermitidae) species and their hybrids in laboratory-rearing conditions. Correlations between the daily wood consumption and several demographic variables within colonies were established. Linear models varied across all species mating types with R2 values greater than 0.8 for all demographic variables. For colonies from all mating combinations, Pearson’s correlation coefficient values were greater than 0.94 between their daily wood consumption and both the number of workers and total number of termites, and greater than 0.91 between daily wood consumption and colony mass. Therefore, in colonies with fixed laboratory conditions, their average daily wood consumption determination, which is nondestructive on colonies, can be used to infer colony size of subterranean termites.

This study evaluated the effect of wood extracts from Tectona grandis, Dalbergia sissoo, Cedrus deodara, and Pinus roxburghii combined with linseed oil as protectants of two non-durable wood species against the termite, Heterotermes indicola. Heartwood blocks (19 × 19 × 19 mm) and wood shavings were extracted using an ethanol/toluene (2:1) solvent system. Results of choice and no-choice tests with solvent-extracted and non-extracted heartwood blocks showed greater wood mass loss from termite feeding on solvent-extracted blocks compared with non-extracted blocks for all wood species. Significantly higher termite mortality was observed after termite exposure to non-extracted blocks compared with extracted blocks for all durable species. Sapwood blocks of two non-durable wood species (southern pine and cottonwood) were vacuum/pressure impregnated separately with each of the four types of extract at a concentration of 7.5 mg ml−1, linseed oil (20%) and a mixture of oil (20%) and extracts (4.25 mg ml−1) for the laboratory and field tests. Results showed that extract-oil mixture imparted significantly higher termite resistance compared with linseed or extracts alone under laboratory conditions. This apparent synergistic effect was clearly noted when linseed oil was combined with extracts from T. grandis or D. sissoo followed by an extract-oil mixture using C. deodara. These extract oil mixtures showed significantly less weight loss for the treated non-durable wood species and higher termite mortality (83–100%) compared with the control treatments and other extract-linseed oil mixtures tested. Treatment of both non-durable wood species with T. grandis + oil and D. sissoo + oil prevented termite damage compared with other treatments when blocks and stakes were exposed in the field for a period of 2 years. Results of the current study indicated that a mixture of a particular heartwood extract with linseed oil has potential to be used as environmentally friendly wood protectants.

This study evaluated the effects of three different land use types: mango orchards, maize fields and communal grazing lands on termite species distribution in the Vhembe District, Limpopo Province, South Africa. The main objective was to identify the termite species found in the area and investigate the effect of land use on termite species. Termites were collected from six study sites using a standardized transect sampling protocol and baiting methods in a transect of 2 × 100 m during the dry and wet seasons. A total of 18 termite species from 2 families (Termitidae and Rhinotermitidae), 5 subfamilies (Macrotermitinae, Amitermitinae, Apicotermitinae, Nasutitermitinae and Cubitermitinae) and 11 genera (Allodontotermes, Ancistrotermes, Macrotermes, Microtermes, Odontotermes, Microcerotermes, Rhadinotermes, Trinervitermes, Psammotermes, Schedorhinotermes and Cubitermes) were recorded. A higher species diversity index was observed for the wet season. Communal grazing resulted in a higher Shannon diversity index (H′) of 2.23 and Simpson diversity index (1-D) of 0.84 followed by mango orchard (H′ = 1.41, 1-D = 0.68), while maize field recorded the lowest (H′ = 1.07, 1-D = 0.48). Macrotermitinae constituted 77% of the total number of species recorded across all the land use types. Edible termite species recorded are important in rural communities to supplement human protein requirements and they provide ecosystem services thus, there is a need for studies that quantify the trade-off between costs (crop damage) and benefits of maintaining termites in agricultural landscapes.

Concerns on efficacies of termiticides used for soil treatment to prevent Formosan subterranean termite (Coptotermes formosanus Shiraki) infestations have prompted pest control companies to suggest that retreatments are necessary after flooding of homes. Therefore, to address concerns about the efficacy of termiticides after flooding, we designed a flooding simulation experiment in the laboratory. We used four formulated termiticides containing fipronil, imidacloprid, chlorantraniliprole, or bifenthrin as active ingredients (a.i.) and two colonies of field-collected C. formosanus for this study. Evaluations of each chemical at concentrations of 1, 10, and 25 ppm in both sand and soil were conducted in the laboratory by comparing termite mortalities in no-choice bioassays after exposure to flooded (for 1 wk) and unflooded substrates. Toxicity from bifenthrin and fipronil were not affected by flooding regardless of substrate type except at the lowest concentration tested. Toxicity from chlorantraniliprole was lower in flooded sand at 1 ppm but otherwise similar among flooding treatments. In flooded soil, toxicity from chlorantraniliprole was low at 1 ppm, but unexpectedly high in flooded conditions at 10 and 25 ppm. For all concentrations of imidacloprid-treated sand, mortality of C. formosanus was reduced after a flood. However, like chlorantraniliprole, 10 and 25 ppm of imidacloprid-treated soil in flooded conditions resulted in an increased toxicity on C. formosanus. Our study supports the idea that chemicals with a higher water solubility like imidacloprid may require a home to be retreated with less water-soluble termiticides or baits after a flood.

Termites feed on a carbon-rich but nitrogen-poor diet and evolved efficient nitrogen conservation strategies. It was previously suggested that during time of low access to resources (i.e., starvation), subterranean termites (Rhinotermitidae) colonies would adopt an energy conservation strategy by cannibalizing soldiers, a dependent caste. However, such hypothesis was tested with relatively small groups of foragers, which may not have reflected how resources are reallocated in whole colonies when food (carbon) is scarce. The current study subjected 2-year-old colonies (≈ 3000 termites with all castes and instars) to starvation, in order to reexamine if cannibalism is part of an active energy conservation strategy. Within 12 days of starvation, eggs and larvae were all cannibalized, followed by young workers. Soldiers then died marginally faster than old workers. By 22 days, cannibalism was no longer observed, and the king and queen were among the last individuals to die. Termites that engaged in the process of ecdysis with no energetic resources, failed to molt, died in the process, and the subsequent cannibalism was a passive mortality-driven process. Therefore, cannibalism was primarily the result of the inherent termite behavior for recycling nitrogen resources. The hemimetabolous developmental pathway, the difference of timing in the molting cycle of termite instars and the relatively rapid exhaustion of soldiers, indirectly determined the sequence of starvation-induced mortality and subsequent cannibalism. Although termites have evolved efficient nitrogen conservation strategies, they have not evolved an efficient carbon conservation strategy, which is essentially limited to keeping the primary reproductives alive as long as possible.

Metagenomics and transcriptomics have had some success analyzing community and functional ecology of the termite gut, but carbon utilization ecology and the effect of diet on the gut community are not well understood. This study was done to determine the effect of three hardwood tree types, oak (Quercus spp.), red maple (Acer rubrum), and tupelo (Nyssa aquatica) on the termite species, Reticulitermes flavipes in the family Rhinotermitidae. Termite abdomen homogenates were incubated on agar plates containing three common carbon sources in the termite gut, namely, acetate, cellobiose, and phenol under aerobic and anaerobic conditions. Bacterial growth was higher on cellobiose than any other carbon source. Higher bacterial growth on cellobiose was observed from termite colonies feeding on oak than on phenol from the other two wood types. The difference between aerobic and anaerobic conditions was not significant. A bacterium, Acinetobacter tandoii isolated and identified from our previous study was subjected to high concentrations of phenol as the sole carbon source and this bacterium was able to degrade phenol concentration up to 600 mg/L.

As a social insect, termites have different castes and division of labor in a colony. Investigating the social behavior of subterranean termites is a challenge due to the cryptic nature and large colony size. Planar arenas are commonly used to study these termites under laboratory conditions, and have provided several advantages. However, there is no means to designate areas such as a royal chamber or central nest from foraging sites because reproductives can move freely across arenas. In this study, we examined the minimum passing size of different castes of Coptotermes formosanus Shiraki (Blattodea: Rhinotermitidae), in order to develop a reproductive excluder and correlated minimum passing size with head widths and heights. We found that workers and soldiers of C. formosanus were able to pass through a gap greater than or equal to 0.7 mm. Our results showed that there are significant differences in the head width and height based on castes and head height was more critical than head width to determine passing size. We further confirmed feasibilities of the reproductive excluders using incipient colonies of C. formosanus. Confining reproductives using the excluder in laboratory experiments will provide more chances to study the royal chamber and central nest independently of foraging sites.

Species identification in the genus Reticulitermes is often difficult because of ambiguous morphological characters. Challenges in Reticulitermes spp. recognition have also been encountered in East Asia, including Taiwan. Because of unknown Reticulitermes taxa in Taiwan and the possible origin of alien Reticulitermes kanmonensis Takematsu in Japan and Korea, reexamining Reticulitermes fauna in Taiwan is imperative. To clarify the Reticulitermes fauna in Taiwan, this study applied two mitochondrial genes (cytochrome oxidase subunit II [COII] and 16S rDNA) and morphological characters for species delimitation. Reticulitermes specimens collected from 63 localities across the main and adjacent islands of Taiwan were analyzed. Phylogenetic analyses, morphological comparisons, and ecological traits suggested the existence of three species in Taiwan: Reticulitermes flaviceps (Oshima), R. kanmonensis, and Reticulitermes leptomandibularis Hsia and Fan. Altitudinal distributions among the three Reticulitermes termites tended to differ: R. flaviceps adapted to low hills, but R. kanmonensis and R. leptomandibularis occurred in medium mountainous areas. The combined data, including haplotype diversities and distribution range, suggest that 1) R. flaviceps is an endemic species and only found in Taiwan; 2) R. kanmonensis and R. leptomandibularis are both native species in Taiwan and China; 3) Japanese R. kanmonensis populations originated from southern China and/or Taiwan and that Korean populations were possibly introduced from Japan.

Laboratory studies of Coptotermes formosanus Shiraki (Blattodea: Rhinotermitidae) often employ the use of field-collected foraging populations of individuals as defined colonies. The biological relevance of this practice is often called into question, because these colonies lack a full composition of reproductive castes and brood, which may have physiological and behavioral consequences. Rearing intact laboratory colonies can be done; however, it is time-consuming and labor-intensive. The artificial fusion of field-collected foraging populations with a young, laboratory-reared incipient colony may provide whole, intact colonies for laboratory research. The current study measures survivorship of fused colonies using laboratory-reared complete incipient colonies ranging in age from 0 to 5 mo, fused with 100 workers and 10 soldiers from field-collected populations of different colonial origin. Results indicate that 60% of colony fusion was successful when the incipient colony introduced is 5 mo of age. This method of colony fusion will provide researchers with intact colonies using minimal resources.

BackgroundA decade ago, the mixed reproductive strategy Asexual Queen Succession (AQS) was first described in termites. In AQS species, the workers, soldiers and dispersing reproductives are produced through sexual reproduction, while non-dispersing (neotenic) queens arise through automictic thelytokous parthenogenesis, replace the founding queen and mate with the founding king. As yet, AQS has been documented in six species from three lineages of lower (Rhinotermitidae) and higher (Termitinae: Termes group and Syntermitinae) termites. Independent evolution of the capacity of thelytoky as a preadaptation to AQS is supported by different mechanisms of automixis in each of the three clades. These pioneering discoveries prompt the question on the extent of thelytoky and AQS in the diversified family of higher termites.ResultsHere, we investigated the capacity of thelytoky and occurrence of AQS in three species from the phylogenetic proximity of the neotropical AQS species Cavitermes tuberosus (Termitinae: Termes group): Palmitermes impostor, Spinitermes trispinosus, and Inquilinitermes inquilinus. We show that queens of all three species are able to lay unfertilized eggs, which undergo thelytokous parthenogenesis (via gamete duplication as in C. tuberosus) and develop through the transitional stage of aspirants into replacement neotenic queens.ConclusionsThe breeding system in P. impostor is very reminiscent of that described in C. tuberosus and can be characterized as AQS. In the remaining two species, our limited data do not allow classifying the breeding system as AQS; yet, also in these species the thelytokous production of neotenic females appears to be a systematic element of reproductive strategies. It appears likely that the capacity of thelytokous parthenogenesis evolved once in the Termes group, and may ultimately be found more widely, well beyond these Neotropical species., info:eu-repo/semantics/published

Of eight termite species found in Egypt, the subterranean termite Psammotermes hypostoma Desneux is considered as the most important serious pest, which destroy the wooden structures in buildings and other wood products or any material containing cellulose. Therefore, cellulases enzymes are considered the main enzymes in the digestive system of termite. The termite digestive system is considered a target for best control. This report discusses the descriptive variations of alimentary canals for the worker and the soldier, also, the detection of three digestive enzymes; two of them belonging to cellulases enzymes (endo-β-1,4-glucanase, and cellobiase (β -glucosidase) and the third is amylase in guts extracts from the termite workers and soldiers. The workers had higher endo-β-1,4-glucanase and amylase activities, while soldiers had higher cellobiase (β-gl`ucosidase) activity. It is clear that the presence of α-amylase in the digestive system of P. hypostoma workers and soldiers means that this species of termite is able to decompose starch, which explains why termites attack grain silos. Effect of temperature and PH on enzyme activity showed that the optimum temperature /PH for workers were 70 °C/ PH6 for endo-β-1,4-glucanase, 50 °C/PH6 for cellobiase (β -glucosidase) and 70 °C/pH 7 for amylase, while, in case of soldiers, optimum temperature/pH were 70 °C/PH6 for endo-β-1,4-glucanase, 40 °C/PH6 for cellobiase (β-glucosidase) and 60 °C/PH 7 for amylase. This work is the first in Egypt concerning the study of the enzymes activities of the digestive system of termite and may be considered an initial step to contribute to control this species of termite by the development of new termiticides.

The subterranean termite Heterotermes indicola (Blattodea: Rhinotermitidae) is a serious pest to wood in service causing significant annual economic loss in Southeast Asia. In the present study, silver oak (Grevillea robusta A. Cunn.) (Proteaceae) leaf extract was investigated for its termiticidal properties against the termite H. indicola in laboratory tests. An ethanol-solvent system was used to remove the extract from dry leaf powder via Soxhlet apparatus. A dose-dependent foraging response and mortality was observed after continuous exposure to a dose range of 1–20 mg/mL of extract based on dry extract weight. Results indicated that maximum (>90%) termite mortality occurred at 20 mg/mL along with a significant reduction in termite tunneling activity. An LC50 was calculated at 5.47 mg/mL using the concentration series data. In filter paper antifeeding and repellency bioassays, a significant reduction in the total population of gut protozoa compared to untreated and negative controls (solvent) was observed. After 2 weeks of no-choice continuous feeding on filter paper treated at 20 mg/mL, hindgut protozoan population was reduced by 62.90%. The extract conveyed resistance to the non-durable cotton wood and chir pine after vacuum pressure treatment. At the highest concentration tested, 100% mortality was recorded after exposing termites to cotton wood and chir pine treated with silver oak leaf extract. HPLC-DAD-ESI-MS results of the extract showed high level of phenolic compound, alkyl-resorcinol. Results indicated that silver oak leaf extract has termiticidal properties and could be of value in the development of botanical insecticides for termite control in wood products.

SummaryTermites are model social organisms characterized by a polyphenic caste system. Subterranean termites (Rhinotermitidae) are ecologically and economically important species, including acting as destructive pests. Rhinotermitidae occupies an important evolutionary position within the clade representing an intermediate taxon between the higher (Termitidae) and lower (other families) termites. Here, we report the genome, transcriptome and methylome of the Japanese subterranean termite Reticulitermes speratus. The analyses highlight the significance of gene duplication in social evolution in this termite. Gene duplication associated with caste-biased gene expression is prevalent in the R. speratus genome. Such duplicated genes encompass diverse categories related to social functions, including lipocalins (chemical communication), cellulases (wood digestion and social interaction), lysozymes (social immunity), geranylgeranyl diphosphate synthase (social defense) and a novel class of termite lineage-specific genes with unknown functions. Paralogous genes were often observed in tandem in the genome, but the expression patterns were highly variable, exhibiting caste biases. Some duplicated genes assayed were expressed in caste-specific organs, such as the accessory glands of the queen ovary and frontal glands in soldier heads. We propose that gene duplication facilitates social evolution through regulatory diversification leading to caste-biased expression and subfunctionalization and/or neofunctionalization that confers caste-specialized functions.Significance StatementTermites are model social organisms characterized by a sophisticated caste system, where distinct castes arise from the same genome. Our genomics data of Japanese subterranean termite provides insights into the evolution of the social system, highlighting the significance of gene duplication. Gene duplication associated with caste-biased gene expression is prevalent in the termite genome. Many of the duplicated genes were related to social functions, such as chemical communication, social immunity and defense, and they often expressed in caste-specific organs. We propose that gene duplication facilitates social evolution through regulatory diversification leading to caste-biased expression and functional specialization. In addition, since subterranean termites are ecologically and economically important species including destructive pests in the world, our genomics data serves as a foundation for these studies.

Linear and geometric morphometrics approaches were conducted to analyze the head capsule (HC) shape of collected soldier caste specimens of Coptotermes from various locations in Indonesia. The soldiers’ morphology was observed and measured. The results of the principal component analysis of the group of all species showed two important groups of variables, i.e., the body size and setae characteristics of the pronotum and head. The multicollinearity of the morphometric variables showed the importance of body measurements as well as important alternative characteristics such as the pronotum setae (PrS) and HC setae. Four trends of HC shape were observed across the species. Interestingly, three extreme shapes were depicted by geometric morphometrics of the C. gestroi HC. The phylogenetic tree inferred from 12S and 16S mitochondrial gene fragments showed high confidence for C. gestroi populations. The lateral expansion of the posterior part of the HC across the species was in accordance with the increasing of the number of hairlike setae on the pronotum and HC. These differences among species might be associated with mandible-force-related defensive labor and sensitivity to environmental stressors.

Coptotermes gestroi (Wasmann) (Blattodea: Rhinotermitidae) is a subterranean termite species from Southeast Asia which has been unintentionally introduced to many parts of the world through commerce and modern transportation. Known for causing extensive damage to timber used in the built environment, the termite also has a habit of nesting in carton nests in wood and wooden structures in buildings. As so little is known of its breeding system, colony, and genetic structure, we initiated work to sequence its genome with an Illumina HiSeq™ 2000 sequencer. In this publication, we announce our paired-end sequencing data and report the isolation of 119,190 microsatellite markers from our DNA assembly. The microsatellite marker reported in this publication can be used to elucidate the mating system and genetic structure of this highly invasive termite species. Additionally, in this announcement the study authors make the Bio Project sequence accession number SRR13105492 accessible from the Sequence Read Archive database.

Subterranean termites are hemimetabolous social insects where most of the individuals in a colony molt on a regular basis until they die. Nitrogen is a limiting growth factor in wood-feeding insects, such as termites. Because the exuviae of molting termites are consumed by nestmates, it is possible that exuviae represent a potential source of nitrogen that could be recycled and be part of the overall nitrogen conservation strategy of the colony. Although it was documented that cockroach exuviae can contain relatively high levels of nitrogen, the nitrogen content of subterranean termite exuviae has not been examined. This study determines the nitrogen content of Coptotermes gestroi (Wasmann) exuviae collected from four-year-old laboratory colonies using a carbon/nitrogen analyzer. Coptotermes gestroi exuviae contained 11.24 ± 0.64% N (Mean ± SD). The exuviae had a higher proportion of nitrogen than whole bodies of termites (~10.46%), wood (~0.12%), and organic soil (~2.49%). These results support the importance of exuviae consumption by nestmates during the ecdysis process as an aspect of nitrogen conservation strategies in Coptotermes colonies., Exoskeleton; Nitrogen conservation; Molting

Simple Summary Subterranean termite colonies can be eliminated using baiting systems. However, for a given bait to be effective, the active ingredient must be lethal at concentrations that are also palatable to termites. The insect molting hormone, 20-hydroxyecdysone (20E), has potential for use in termite baits, but its palatability to termites has not been examined. The purpose of this study was to determine what concentrations of 20E, if any, cause termite workers to feed less readily. To test this, paper disks were treated with various concentrations of 20E. Groups of 1000 termites of three different species; the Formosan, the Asian and the Eastern subterranean termite; were placed in arenas. The termites had the option of following a path to feed on either a paper disk containing the 20E, or an untreated disk, and the amount of paper consumed was then compared. The results showed that the Asian subterranean termite had the least tolerance for the 20E, the Formosan subterranean termite had a reduced tolerance, and the presence of the 20E had no impact on the Eastern subterranean termite. Abstract Effective active ingredients in toxicant bait formulations must be non-deterrent to insect feeding behavior at lethal concentrations. This study evaluated feeding deterrence for Coptotermes formosanus Shiraki, C. gestroi (Wasmann), and Reticulitermes flavipes (Kollar) when provided access to cellulose impregnated with various concentrations of the insect molting hormone, 20-hydroxyecdysone (20E). Termites were exposed to 20E concentrations of 200, 500, 1000 and 2000 ppm and to noviflumuron at 5000 ppm in a 24 h choice-test, and the mass of substrate consumption from treated and untreated media pads was compared for each treatment. 20E feeding deterrence was detected at 500, 1000 and 2000 ppm for C. gestroi, and at 2000 ppm for C. formosanus. No significant differences in consumption of treated and untreated substrate was detected at any concentration for R. flavipes. Potential methods for reducing deterrence are discussed.

There are 28 invasive termite species, most belong to two families, the Kalotermitidae (esp. Cryptotermes spp.) and Rhinotermitidae (esp. Coptotermes spp.). Six invasive termite species are known to have spread into natural habitats, but little direct research has been conducted into their ecological impacts. Predictions based on indirect research (natural durability of commercial wood species) suggest fast-growing, pioneer tree species with low density wood, perhaps notably legumes, are most vulnerable to invasive termites, but even slow growing climax tree species may succumb. Cryptotermes will likely have less ecological impact, due to small colonies attacking dead branch stubs in the canopy. Coptotermes will likely have greater impact, due to large colony sizes and nesting in living trees, which they hollow out and can kill. There are no studies of invasive termites on native termites, other wood-eating insects, or predators, such as ants, showing considerable scope for future research.

A new infestation of the Formosan subterranean termite, Coptotermes formosanus Shiraki (Blattodea: Rhinotermitidae), was discovered in Canyon Lake, Riverside County, California. We used three mitochondrial DNA (COI, COII, and 16S) and seven polymorphic microsatellite markers to characterize the genetic relationship of the colony with two other colonies that were collected in 1992 and 2018 in La Mesa, San Diego County. Maximum likelihood phylogeny of C. formosanus based on concatenated COI and COII sequences revealed that the two La Mesa populations (CA01 and CA02) and the Canyon Lake population (CA03) were from different maternal lineages. Based on the 14 COII haplotypes of C. formosanus found world-wide, CA01 and CA02 belonged to a haplotype widely distributed across the United States, while CA03 was grouped under a haplotype predominantly found in Asia. Microsatellite allele frequencies across all loci for both La Mesa populations were relatively similar, but significant genetic differences were found between CA02 and CA03 colonies (FST = 0.24; Dest = 0.30; G″ ST = 0.55; P < 0.01).

The development of baits for subterranean termite control over the past 25 yr has provided cost-effective alternatives to liquid termiticide treatments. Current bait products use one of the few available benzoylurea chitin synthesis inhibitors (CSIs) labeled for subterranean termites. These insecticides are used because of their nonrepellency, their slow-acting mode of action, and their dose-independent lethal time. Although many studies have provided ample evidence of the efficacy of CSI baits for subterranean termite colony elimination, most have focused on hexaflumuron and noviflumuron. However, bait products using alternative CSIs have not received the same level of scrutiny, limiting the amount of evidence proving their efficacy. One such compound is novaluron, the active ingredient currently used in the Trelona ATBS—Advance Termite Baiting System bait product. The current study independently tested the efficacy of this commercially available bait formulation against whole colonies of Coptotermes gestroi (Wamann) (~63,910 workers) in the laboratory, using an extended experimental setup to simulate a 15-m foraging distance from the central part of the nest to the bait, while having access to alternative food sources. Treated colonies progressively ceased to feed on wood items within 45 d after being provided access to the novaluron bait formulation, with a subsequent progressive collapse of the population, leading to colony elimination by 91 d. This study therefore confirms the efficacy of novaluron baits against subterranean termites, and currently remains one of the few CSIs that can be applied for the successful control of Coptotermes infestations.

The nutritional properties of subterranean termite exuviae (shed exoskeletons) are not well-known because obtaining the large quantities necessary for investigation is difficult. A method for collecting large numbers of exuviae is reported here for the Asian subterranean termite, Coptotermes gestroi (Wasmann) (Blattodea: Rhinotermitidae), an invasive and economically important tropical termite species. In this study, groups of 1,000 C. gestroi workers from 4-yr-old laboratory colonies (n = 3) were allowed to feed on a media pad dyed with Nile Blue A for 2 d. Approximately 16% of the original 1,000 workers did not uptake dye. These individuals were then placed into a Petri dish with dyed filter paper and checked hourly (10:00 A.M. to 10:00 P.M.) for 7 d. Newly molted workers and those individuals that started turning blue were removed to prevent feeding on exuviae. An average of 14 workers molted per d that yielded an average of 12 exuviae with an overall mean of 86 exuviae collected over the 7 d study period. We also found the number of individuals that acquired dye during the study significantly decreased by d. However, variables such as the number of exuviae, newly molted individuals, and cadavers were not correlated with d of collection because termites molt asynchronously. Resumen Las propiedades nutricionales de las exuviae de termitas subterraneas (exoesqueletos desprendidos) no son bien conocidas porque es dificil de obtener las grandes cantidades necesarias para su investigacion. Aqui se informa un metodo para recolectar grandes cantidades de exuvias para la termita subterranea asiatica, Coptotermes gestroi (Wasmann) (Blattodea: Rhinotermitidae), una especie de termita tropical invasora y economicamente importante. En este estudio, se permitio que grupos de 1,000 trabajadores de C. gestroi de colonias de laboratorio de 4 anos de edad (n = 3) se alimentaran de una almohadilla de medio tenida con Azul Nilo A durante 2 dias. Aproximadamente el 16% de los 1,000 trabajadores originales no tomaron tinte. A continuacion, estos individuos se colocaron en un plato Petri con papel de filtro tenido y se controlaron cada hora (10:00 A. M. a 10:00 P. M.) durante 7 dias. Los trabajadores recien mudados y los individuos que comenzaron a ponerse azules fueron retirados para evitar alimentarse de las exuvias. Un promedio de 14 trabajadores mudaron por dia, lo que produjo un promedio de 12 exuvias con una media general de 86 exuvias recolectadas durante el periodo de estudio de 7 dias. Tambien encontramos que el numero de individuos que adquirieron tinte durante el estudio disminuyo significativamente por dia. Sin embargo, las variables como el numero de exuvias, los individuos recien mudados y los cadaveres no se correlacionaron con los dias de recoleccion porque las termitas mudan asincronicamente. Key Words: Coptotermes gestroi; ecdysis; exoskeleton; molting; dye; histological stains View this article in BioOne

Climate change impacts the current and potential distribution of many insects, since temperature is often a limiting factor to where the insects can survive. The Formosan subterranean termite, Coptotermes formosanus Shiraki (Blattodea: Rhinotermitidae), has never been reported in South Korea despite its close proximity to 2 countries (China and Japan) where this economically important pest has been reported. This may be due to the average winter temperature in South Korea which is below 4 °C, the lower limit of the current distribution range of Formosan subterranean termite. However, with climate change leading to increased temperatures, South Korea may be susceptible to successful invasion by Formosan subterranean termite. The objective of this study is to estimate the future possible distribution of Formosan subterranean termite in Korea based on temperature. Climate data from Korea showed a significant increase of 2.19 °C per 100 yr in average annual temperature from 1910 to 2018. Previous and current average winter temperatures were higher than 4 °C only in Jeju, and most provinces did not exceed 4 °C, except for some southern cities such as Busan in 2000 to 2019. With the estimated rate of temperature rises, winter temperatures in Gyeongsangnam-do will exceed 4 °C starting from 2020, and Jeollanam-do will exceed 4 °C from 2060. Coupled with the statistically significant, increased annual trade between Korea and other countries (China, Japan, Taiwan, and the USA) where C. formosanus is currently distributed, we predict that Formosan subterranean termite will become established in South Korea, probably starting from a southern trade port such as Busan.

Background Coptotermes sjostedti Holmgren (Isoptera:Rhinotermitidae) is one of the major termite species found infesting woods and other plant materials in Africa. Bioassays were carried out at the Arboretum of the Department of Forestry and Wildlife Resources Management, University of Calabar, Nigeria to investigate the effect of oils from the kernel of Jatropha curcas L. and Azadirachta indica oils A. Juss against the African subterranean termite (Coptotermes sjostedti Holmgren). Treatments comprised of the plant oils and Solignum (a synthetic termiticide, serving as positive control) applied at the rate of 5, 10 and 15 mL per 100 cm3 of the wood from seven plant species. Untreated woods also served as control. Seven wood species were placed in a test arena and artificially infested with 50 termites per unit. The setup was a randomized complete block design with four replicates. Data on termite mortality and wood weight loss were recorded. Results The use of 10 and 15 mL of J. curcas oil caused more than 90% mortality of C. sjostedti, after 96 h, kept wood consumption by the insect below 6.0% after 3 months, and these outcomes were similar to that of Solignum at the same concentrations. About 35.0–65.2% reduction in weight was observed among untreated woods from the tested woods, indicating their susceptibility to C. sjostedti attacks. Correlation analysis shows a significant (r > − 0.900; P Conclusion The use of J. curcas oil at 10 mL per 100 cm3 of wood could be a potent alternative to Solignum for the control of C. sjostedti.

This work assesses damage caused by Coraebus undatus (Fabricius) (Coleoptera: Buprestidae) and Reticulitermes grassei Clément (Blattodea: Rhinotermitidae) in managed cork oak forests from the southern Iberian Peninsula. Lesions were diagnosed and quantified in relation to the following features: height and orientation in the trunk, diameter at breast height, solar exposure, understory presence and orography. The distribution patterns of lesions in the study area across 12 plots and in the trunk of the trees were also analyzed. The study was performed in “Sa de Hornachuelos” Natural Park (Córdoba, Spain) and the research area encompassed 12 environmentally-restored sampling plots. Data were recorded from 2007 to 2014, with yearly sampling from late June to mid-September, corresponding to the cork extraction period, since lesions caused by these insects are well distinguishable promptly after bark removal. The results reveal that C. undatus has low population levels and a non-uniform distribution pattern in the study area as well as in the trunk of the tree. It shows preference for medium height but not by any trunk orientation. R. grassei also shows low infestation levels and a preference to affect the trunk’s base. Comparatively, C. undatus showed higher infestation levels than R. grassei. The location of damage was also different, since galleries made by C. undatus predominated at intermediate trunk heights while those of R. grassei were more frequent at lower heights. Our results further showed a low co-occurrence of both species in the same tree trunks, which could be explained in terms of overlapping in the distribution areas of both species. These results provide background information that will enable natural resources managers to detect changes and trends of these species and inform future management decisions.

Termites, being vulnerable to parasitic or pathogenic infections due to large number of individuals living together in colonies, have evolved various behavioral and physiological tactics to resist the infections by those pathogens. Locomotion can help termites collect information on parasites and accordingly exhibit hygienic behaviors. Termites inevitably encounter entomopathogenic fungi during nesting and foraging. However, how these fungal pathogens influence locomotion of termites and how hygienic behavior benefits their survival remains unknown. Here, we examined locomotion alteration of the termite Reticulitermes chinensis (Isoptera: Rhinotermitidae) after infections with different concentrations of the entomopathogenic fungus Metarhizium anisopliae (Hypocreales: Clavicipitaceae). When R. chinensis was isolated, the low concentration (5 × 103 conidia/ml) significantly increased termite locomotion after 6, 12, and 24 h compared with control. However, the high concentrations (5 × 107, 5 × 109 conidia/ml) significantly decreased termite locomotion after 48 h, and termite survival was also significantly lower at 5 × 107 and 5 × 109 conidia/ml compared with the low concentrations and the control. When R. chinensis was in group, however, the locomotion significantly increased 24 h after exposure to 5 × 103 and 5 × 109 conidia/ml but was normalized after 48 h of exposure compared with the control. Allogrooming was significantly higher at 5 × 103 and 5 × 109 conidia/ml compared with the control. The fungal infection did not result in significantly higher mortality of the group termites probably owing to their allogrooming. These findings enhance our understanding on how a termite species copes with biotic stress (i.e., fungal infections) via adaptive behaviors.

International audience; Phylogeny and classification The worldwide family Rhinotermitidae, or subterranean termites, comprises 15 genera and more than 300 species. They occupy an intermediate position between the so-called "lower" and "higher" termites and so are often referred to as "intermediate" termites (1). The Rhinotermitidae appears to be paraphyletic, with most researchers placing the clade with Coptotermes and Heterotermes as a sister group to the Termitidae. Some researchers regard the Serritermitidae as paraphyletic within the Rhinotermitidae-Termitidae clade, while others place it as a basal group of Rhinotermitidae, near other basal groups such as Rhinotermes, Prorhinotermes, and Schedorhinotermes. Other researchers feel that Serritermitidae lies at the crossroads of worker caste evolution in termites, between the lower termites and the Rhinotermitidae+Termitidae clade. The most basal rhinotermitid taxa, such as Rhinotermes, diverged from the other lower termites less than 100 MA ago. The latest literature reviews indicate that the well-known, more derived genera Reticulitermes and Coptotermes+Heterotermes consistently form two distinct clades in a monophyletic branch within the family (2). These three genera account for more than half the species in Rhinotermitidae (184 of 305) and are the best studied within the family. The native ranges of these three genera (Reticulitermes, Coptotermes and Heterotermes) are all broad but fairly distinct. Coptotermes and Heterotermes are largely pantropical, although Heterotermes does not occur in Africa. Coptotermes is absent from the Nearctic and Palearctic regions. Reticulitermes naturally occurs exclusively within temperate areas. The Coptotermes+Heterotermes clade and Reticulitermes separated about 60 MA, according to various researchers. However, based on historical biogeography, modern Reticulitermes species resulted from cladogenesis and are highly taxonomically distinct. More ancient fossils of the different genera have been found in Europe, and they geologically date back to around 38 MYA. In a recent molecular phylogeny for Coptotermes, created using the complete mitochondrial genome, the genus is composed of numerous poorly supported branches. This result is partly due to the high level of synonymy in the present nomenclature and does not help clearly differentiate the species. However, speciation patterns were relatively clear in Australia, where this clade is the best defined. Consequently, this genus should be revised to deal with the high levels of synonymy in some locations (3).