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Termites are social cockroaches distributed throughout warm temperate and tropical ecosystems. The ancestor of modern termites roamed the earth during the early Cretaceous, suggesting that both vicariance and overseas dispersal may have shaped the distribution of early diverging termites. We investigate the historical biogeography of three early diverging termite families –Stolotermitidae, Hodotermitidae and Archotermopsidae (clade Teletisoptera) – using the nuclear rRNA genes and mitochondrial genomes of 27 samples. Our analyses confirm the monophyly of Teletisoptera, with Stolotermitidae diverging from Hodotermitidae + Archotermopsidae approximately 100 Ma. Although Hodotermitidae are monophyletic, our results demonstrate the paraphyly of Archotermopsidae. Phylogenetic analyses indicate that the timing of divergence among the main lineages of Hodotermitidae + Archotermopsidae are compatible with vicariance. In the Stolotermitidae, however, the common ancestors of modern Porotermes Hagen and Stolotermes Hagen are roughly as old as 20 and 35 Ma, respectively, indicating that the presence of these genera in South America, Africa and Australia involved over‐water dispersals. Overall, our results suggest that early diverging termite lineages acquired their current distribution through a combination of over‐water dispersals and dispersal via land bridges. We clarify the classification by resolving the paraphyly of Archotermopsidae, restricting the family to Archotermopsis Desneux and Zootermopsis Emerson and elevating Hodotermopsinae (Hodotermopsis Holmgren) as Hodotermopsidae (status novum). [ABSTRACT FROM AUTHOR]

Urban ecosystems are characterized by 'urban exploiters': species that thrive in the modified environment of cities. Few insects have been categorized as such, in part because they are usually considered as pests first, in part because many studies do not identify to species, and in part because many insects can survive in small vegetated areas within the urban matrix. Some termites may be prime examples of urban exploiters; Coptotermes species are rare in natural forests, but are abundant and major pests in urban areas. We investigated the genetic structure of the South East Asian species Coptotermes gestroi in the urban nation of Singapore. There was a panmictic population across the city, yet all 29 colonies were genetically distinct, and many had expanded from recent bottlenecks. There were no significant differences between colonies in vegetated areas (forests and parks), and those in urban habitats. The genetic pattern is similar to some other urban exploiter species in comparable environments, thus confirming C. gestroi is a native species that has become an urban exploiter, the first termite to be considered as such. [ABSTRACT FROM AUTHOR]

Eavesdropping has evolved in many predator-prey relationships. Communication signals of social species may be particularly vulnerable to eavesdropping, such as pheromones produced by ants, which are predators of termites. Termites communicate mostly by way of substrate-borne vibrations, which suggest they may be able to eavesdrop, using two possible mechanisms: ant chemicals or ant vibrations. We observed termites foraging within millimetres of ants in the field, suggesting the evolution of specialised detection behaviours. We found the termite Coptotermes acinaciformis detected their major predator, the ant Iridomyrmex purpureus, through thin wood using only vibrational cues from walking, and not chemical signals. Comparison of 16 termite and ant species found the ants-walking signals were up to 100 times higher than those of termites. Eavesdropping on passive walking signals explains the predator detection and foraging behaviours in this ancient relationship, which may be applicable to many other predator-prey relationships. [ABSTRACT FROM AUTHOR]

The knowledge of the seasonal foraging activity and the numbers of foragers in a colony would be helpful for designing effective termite baiting programs. The current study presents the seasonal activity of Microtermes mycophagus Desneux in a tree plantation in Multan, Punjab, Pakistan, using silk cotton tree wood traps during 2011-2013. The population of M. mycophagus was also estimated using the constant removal method. The number of workers in the underground traps showed a seasonal trend with the highest capture rate occurring during summer and the lowest during winter. The peak in the population (1139 workers/trap) was observed in October after the rainy season. Positive and significant correlation was found between the mean air temperature and the numbers of M. mycophagus workers captured. The constant removal population estimates revealed 16 499-40 265 individuals in the colony of M. mycophagus. Our results suggest that for cost-effective management of the termite species, baiting programs should be started immediately after August when rapid increases in activity of M. mycophagus have been recorded. [ABSTRACT FROM AUTHOR]

A comparative field study was conducted to evaluate the ability of subterranean termites to damage a set of four different plastic materials (cable sheathings) exposed below- and above-ground. Eight pest species from six countries were included, viz., Coptotermesfonnosantis (Shiraki) in China, Japan, and the United States; Coptotennes gestroi (Wasmann) in Thailand and Malaysia; Coptotennes curvignathiis (Holmgren) and Coptotennes kalshoceni (Kemner) in Malaysia; Coptotennes aeinacifonnis (Froggatt) with two forms of the species complex and Mastotennes darwiniensis (Froggatt) in Australia; and Reticulitennesflavipes (Kollar) in the United States. Termite species were separated into four tiers relative to decreasing ability to damage plastics. The first tier, most damaging, included C. acinaaformis, mound-building form, and M. darwiniensis, both from tropical Australia The second tier included C. acinaaformis, tree-nesting form, from temperate Australia and C. kalshooeni from Southeast Asia, The third tier included C. cwvignathtis and C. gestroi from Southeast Asia and C.fonnosamis from China, Japan, and the United States, whereas the fourth tier included only R. flavipes, which caused no damage. A consequence of these results is that plastics considered resistant to termite damage in some locations will not be so in others because of differences in the termite fauna, for example, resistant plastics from the United States and Japan will require further testing in Southeast Asia and Australia. However, plastics considered resistant in Australia will be resistant in all other locations. [ABSTRACT FROM AUTHOR]

The number of recognized invasive termite species has increased from 17 in 1969 to 28 today. Fourteen species have been added to the list in the past 44 years; 10 have larger distributions and 4 have no reported change in distribution, and 3 species are no longer considered invasive. Although most research has focused on invasive termites in urban areas, molecular identification methods have answered questions about certain species and found that at least six species have invaded natural forest habitats. All invasive species share three characteristics that together increase the probability of creating viable propagules: they eat wood, nest in food, and easily generate secondary reproductives. These characteristics are most common in two families, the Kalotermitidae and Rhinotermitidae (which make up 21 species on the invasive termite list), particularly in three genera, Cryptotermes, Heterotermes, and Coptotermes (which together make up 16 species). Although it is the largest termite family, the Termitidae (comprising 70% of all termite species) have only two invasive species, because relatively few species have these characteristics. Islands have double the number of invasive species that continents do, with islands in the South Pacific the most invaded geographical region. Most invasive species originate from Southeast Asia. The standard control methods normally used against native pest termites are also employed against invasive termites; only two eradication attempts, in South Africa and New Zealand, appear to have been successful, both against Coptotermes species. [ABSTRACT FROM AUTHOR]

The literature on pairing and mating behavior in termites indicates that a number of distal antennal segments in dealates of both sexes are often removed during colony foundation, with terms such as amputation, mutilation and cannibalism typically employed to report the phenomenon. Here we propose the use of the phrase 'antennal cropping' to describe the behavior, and assess naturally occurring levels of its occurrence by comparing the number of antennal segments in museum specimens of alates and dealates in 16 species of Australian termites (four families), supplemented by analyzing published data on Coptotermes gestroi. Dealates had significantly fewer antennal segments than alates in 14 of the 16 termite species, with both exceptions belonging to the family Termitidae. Levels of antennal cropping were not significantly different between the sexes but did vary by family. Dealates in the Kalotermitidae removed the most segments (41.3%) and those in the Termitidae removed the fewest (8.9%). We discuss the biological significance of this phylogenetically widespread termite behavior, and suggest that controlled antennal cropping is not only a normal part of their behavioral repertoire but also a key influence that changes the conduct and physiology of the royal pair during the initial stages of colony foundation. [ABSTRACT FROM AUTHOR]

The efficacy of bistrifiuron, a chitin synthesis inhibitor, in cellulose bait pellets was evaluated on the mound-building subterranean termite, Coptotermes acinaciformis (Froggatt). Three concentrations of the bistrifluron were used: 0 (untreated control), 0.5, and 1.0% over an 8 wk period. Both doses of bistrifiuron bait eliminated (viz, termites absent from nest or mound) termite colonies: 83% of colonies (10 of 12) were either eliminated or moribund (viz, colony had no reproductive capacity and decreased workforce) after 8 wk, compared with none of the control colonies. The remaining two treated colonies were deemed to be in decline. Early signs that bistrifiuron was affecting the colonies included: 3 wk after baiting mound temperatures showed a loss of metabolic heat, 4 wk after baiting foraging activity in feeding stations was reduced or absent, and dissection of two mounds at 4 wk showed they were moribund. Colony elimination was achieved in around half or less the time, and with less bait toxicant, than other bait products tested under similar conditions in the field, because of either the active ingredient, the high surface area of the pellets, or a combination of both. This suggests the sometimes long times reported for control using baits may be reduced significantly. The use of a mound building species demonstrated clearly colony level effects before and after termites stopped foraging in bait stations. [ABSTRACT FROM AUTHOR]

A year-long field experiment showed that Reticulitermes flavipes attacked and used single stakes and wooden stake bundles differently in two habitats that varied in alternative forage. In both habitats, the number of termites present in single stakes and stake-bundles increased with stake resource size, and the number of larvae recorded from feeding sites was a close reflection of the number of workers attracted to a given food source. Over 12 mo, more single stakes and stake bundles were heavily attacked and abandoned in the pine woods compared with grassy clearings, Paradoxically, the number of termites present in single stakes and stake bundles was greater in the food-poor habitat (grassy clearings), yet the wood was less consumed compared with the food-rich habitat (pine woods). Use of stake bundles as nests and the slower rate of wood consumption in grassy clearings indicated that termites seemed to value food resources in relative terms, i.e., those termites with abundant alternative food resources consumed quickly and departed, whereas those lacking extra resources ate slowly and settled in. These field results confirm earlier laboratory results that showed that termites modified wood consumption rates dependent on the amount of food available to the colony as a whole. The appearance of mature (physogastric) reproductives (⪢ 1 yr old) in stake bunches in both habitats further indicated that termites track resources and opportunistically shift colony activities and possibly territory boundaries depending on the nature of the resources and other environmental factors. Implications for managing termites with a baiting strategy are discussed. [ABSTRACT FROM AUTHOR]

Presents a study which observed changes in the size of termite colonies. Materials and methods; Results of the study; Discussion of findings.

1. Forager population size of two species of mound-building, subterranean termite (Coptotermes lacteus, Rhinotermitidae and Nasutitermes exitiosus, Termitidae) was estimated using three mark–recapture protocols. These estimates varied widely within and between colonies (≈ 0.3–200 million for C. lacteus and 0.2–3 million for N. exitiosus). The variation in the estimates is explained in part by violation of the assumptions of the protocols. 2. The fat-stain markers, although persistent in the laboratory, faded rapidly in the field, and were transferable from marked individuals to unmarked individuals by cannibalism. 3. Marked individuals did not mix randomly or evenly with unmarked foraging individuals in space or time, as marked individuals were recaptured in widely varying numbers at different feeding sites sampled simultaneously. Importantly, foragers displayed feeding site fidelity and avoided disturbed feeding sites. 4. The likelihood of recapture differed between castes and instars; there was a higher recapture rate of large workers and soldiers relative to smaller workers. 5. The mark–recapture protocols provided inaccurate and unreliable forager population estimates, up to two orders of magnitude larger than direct counts of entire mound colonies. Thus the weighted mean estimates from more complex triple-mark–recapture protocols were not necessarily better than Lincoln index estimates from simpler single-mark–recapture protocols. 6. Mark–recapture studies may provide useful information about forager behaviour and foraging territories. [ABSTRACT FROM AUTHOR]

Competition is a fundamental process in ecology and helps to determine dominance hierarchies. Competition and dominance hierarchies have been little investigated in wood-eating termites, despite the necessary traits of similar resources, and showing spatial and temporal overlap. Competition and dominance between five species of wood-eating termites found in Huangzhou, China, was investigated in three laboratory experiments of aggression and detection, plus a year-long field survey of termite foraging activity. Dominance depended on body size, with largest species winning overwhelmingly in paired contests with equal numbers of individuals, although the advantage was reduced in paired competitions with equal biomass. The termites could detect different species from used filter papers, as larger species searched through paper used by smaller species, and smaller species avoided papers used by larger species. The largest species maintained activity all year, but in low abundance, whereas the second largest species increased activity in summer, and the smallest species increased their activity in winter. The termite species displayed a dominance hierarchy based on fighting ability, with a temporal change in foraging to avoid larger, more dominant species. The low abundance of the largest species, here Macrotermes barneyi, may be a function of human disturbance, which allows subordinate species to increase. Thus, competitive release may explain the increase in abundance of pest species, such as Coptotermes formosanus, in highly modified areas, such as urban systems. [ABSTRACT FROM AUTHOR]

Abstract: Cables sheathed with medium density polyethylene or polyamide were exposed together with highly palatable bait wood to termite faunas in south-eastern and northern Australia, Thailand and southern USA using three methods: below-ground exposure, samples buried horizontally at a depth of 15–30 cm; graveyard method, samples inserted vertically 25 cm deep into the ground; ground contact method, samples placed horizontally on the ground surface, covered with soil and a plastic sheet. Samples were inspected for damage and bait wood replaced annually for six years. No polyamide sample was attacked. Damage to polyethylene was most severe at the Australian sites (across all methods) and in the graveyard method (across all sites), although in Australia in the below-ground method samples experienced greatest damage. Exposing samples together with bait wood within containers for one year, and replenishing bait wood up to three times, i.e. an ‘accelerated’ test method, compared to the standard procedure of providing new bait wood only once a year, resulted in only very limited damage to cables at Asian sites (Macrotermitinae, Coptotermes spp., Malaysia; Coptotermes formosanus, Japan), matching the earlier results for Thailand. But 73% of samples were destroyed by Coptotermes acinaciformis in northern Australia. The Australian termite fauna responds more aggressively to plastic samples than major pest species of termite elsewhere. [Copyright &y& Elsevier]

Abstract: In contrast to the majority of the Order, the dampwood termites of the family Termopsidae found in colder regions can experience frost and snow, either in cool temperate areas at high latitudes (45°), or alpine areas at high elevations (>1000m). This suggests that dampwood termites are adapted to cold climates. We investigated this hypothesis in two dampwood termites, Porotermes adamsoni Froggatt and Stolotermes victoriensis Hill. We measured nest temperatures and atmospheric temperatures of their alpine habitat during winter, and measured survival and recovery at subzero temperatures. We also determined the minimum temperature at which these species remain active and the LT50 values. We used a novel gas chromatographic strategy to examine eight metabolites from individuals of both species collected in winter and summer to identify possible cryoprotectants. Both P. adamsoni and S. victoriensis had significantly higher levels of trehalose, a known cryoprotectant, in winter than in summer; in addition S. victoriensis also had higher levels of unsaturated fatty acid ligands in winter than in summer, consistent with patterns observed for cold adaptation in other organisms. These results are the first to reveal that dampwood termites are adapted to cold climates and use trehalose and unsaturated lipids as cryoprotectants. [Copyright &y& Elsevier]

Graphical abstract Mitochondrial genome phylogenetic tree of the termite subfamily Rhinotermitinae showing divergence time among the main geographic clades. The map depicts the biogeographic realms in which Rhinotermitinae occur, and the arrows show the most likely scenario of dispersal. Highlights • Mitochondrial genome phylogenetic supports the monophyly of Rhinotermitinae and all genera of Rhinotermitinae. • Rhinotermitinae arose about 50 million years ago, after the final phase of the Pangaea breakup. • Rhinotermitinae dispersed worldwide through at least four dispersal events. • Dispersals were both transoceanic dispersals, and dispersals across land bridges. Abstract 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. [ABSTRACT FROM AUTHOR]

Termites sense tiny substrate-borne vibrations through subgenual organs (SGOs) located within their legs' tibiae. Little is known about the SGOs' structure and physical properties. We applied high-resolution (voxel size 0.45 μm) micro-computed tomography (μCT) to Australian termites, Coptotermes lacteus and Nasutitermes exitiosus (Hill) to test two staining techniques. We compared the effectiveness of a single stain of Lugol's iodine solution (LS) to LS followed by Phosphotungstic acid (PTA) solutions (1% and 2%). We then present results of a soldier of Nasutitermes exitiosus combining μCT with LS + 2%PTS stains and scanning electron microscopy to exemplify the visualisation of their SGOs. The termite's SGO due to its approximately oval shape was shown to have a maximum diameter of 60 μm and a minimum of 48 μm, covering 60 ± 4% of the leg's cross-section and 90.4 ± 5% of the residual haemolymph channel. Additionally, the leg and residual haemolymph channel cross-sectional area decreased around the SGO by 33% and 73%, respectively. We hypothesise that this change in cross-sectional area amplifies the vibrations for the SGO. Since SGOs are directly connected to the cuticle, their mechanical properties and the geometric details identified here may enable new approaches to determine how termites sense micro-vibrations. [ABSTRACT FROM AUTHOR]

Abstract: Despite their ecological significance as decomposers and their evolutionary significance as the most speciose eusocial insect group outside the Hymenoptera, termite (Blattodea: Termitoidae or Isoptera) evolutionary relationships have yet to be well resolved. Previous morphological and molecular analyses strongly conflict at the family level and are marked by poor support for backbone nodes. A mitochondrial (mt) genome phylogeny of termites was produced to test relationships between the recognised termite families, improve nodal support and test the phylogenetic utility of rare genomic changes found in the termite mt genome. Complete mt genomes were sequenced for 7 of the 9 extant termite families with additional representatives of each of the two most speciose families Rhinotermitidae (3 of 7 subfamilies) and Termitidae (3 of 8 subfamilies). The mt genome of the well supported sister-group of termites, the subsocial cockroach Cryptocercus, was also sequenced. A highly supported tree of termite relationships was produced by all analytical methods and data treatment approaches, however the relationship of the termites+ Cryptocercus clade to other cockroach lineages was highly affected by the strong nucleotide compositional bias found in termites relative to other dictyopterans. The phylogeny supports previously proposed suprafamilial termite lineages, the Euisoptera and Neoisoptera, a later derived Kalotermitidae as sister group of the Neoisoptera and a monophyletic clade of dampwood (Stolotermitidae, Archotermopsidae) and harvester termites (Hodotermitidae). In contrast to previous termite phylogenetic studies, nodal supports were very high for family-level relationships within termites. Two rare genomic changes in the mt genome control region were found to be molecular synapomorphies for major clades. An elongated stem-loop structure defined the clade Polyphagidae + (Cryptocercus +termites), and a further series of compensatory base changes in this stem-loop is synapomorphic for the Neoisoptera. The complicated repeat structures first identified in Reticulitermes, composed of short (A-type) and long (B-type repeats) defines the clade Heterotermitinae+Termitidae, while the secondary loss of A-type repeats is synapomorphic for the non-macrotermitine Termitidae. [Copyright &y& Elsevier]

Abstract: A phylogenetic hypothesis of termite relationships was inferred from DNA sequence data. Seven gene fragments (12S rDNA, 16S rDNA, 18S rDNA, 28S rDNA, cytochrome oxidase I, cytochrome oxidase II and cytochrome b) were sequenced for 40 termite exemplars, representing all termite families and 14 outgroups. Termites were found to be monophyletic with Mastotermes darwiniensis (Mastotermitidae) as sister group to the remainder of the termites. In this remainder, the family Kalotermitidae was sister group to other families. The families Kalotermitidae, Hodotermitidae and Termitidae were retrieved as monophyletic whereas the Termopsidae and Rhinotermitidae appeared paraphyletic. All of these results were very stable and supported with high bootstrap and Bremer values. The evolution of worker caste and foraging behavior were discussed according to the phylogenetic hypothesis. Our analyses suggested that both true workers and pseudergates (“false workers”) were the result of at least two different origins. Our data support a traditional hypothesis of foraging behavior, in which the evolutionary transition from a one-piece type to a separate life type occurred through an intermediate behavioral form. [Copyright &y& Elsevier]

• Tea Bag Index is originally designed to characterise microbial-driven decomposition. • Application of Tea Bag Index in termite-rich habitats greatly reduced sample size. • Using termite-exclusion barrier preserved full sample size in termite-rich habitats. • We also propose extending the Tea Bag Index to incorporate termite-driven mass loss. • Extended Tea Bag Index validated – contribute to pan-tropical decomposition data. The Tea Bag Index (TBI) is a standardised and cheap method to quantify microbial-driven decomposition by measuring the mass loss of tea within tea bags. Termites are known to damage the bags to access the content, rendering the method less suitable for termite-rich ecosystems. Extension of the TBI to accommodate and incorporate the influence of termites would broaden its applicability to include termite-rich ecosystems, such as tropical forests. We extended the original TBI by applying physical and chemical termite-exclusion methods. Tea mass loss and the proportion of tea bags detected by termites in the original TBI were also recorded to infer the role of termites in litter decomposition. TBI estimates derived from the original and extended TBI were compared, benchmarked against global estimates, and validated with time-series mass loss data. Using the original TBI, we found that termites damaged up to 80 % of tea bags and consumed the recalcitrant fraction of tea in several of them, leaving only 20 % of tea bags from which TBI estimates could be retrieved. The physical termite-exclusion treatment completely eliminated termite-infringement, thus preserving the full sample size for estimating TBI parameters. The chemical termite-exclusion treatment also successfully excluded termites, but potentially inhibited microbial decomposition and made TBI estimates unreliable. In the absence of termite-infringement, both the TBI estimates and time-series analysis revealed a low decomposition rate compared to other measurements in tropical and temperate regions. We propose an extended TBI, in which the physical termite-exclusion treatment is used to preserve the retrieval rate of TBI parameters and reliably measure microbial-driven decomposition, while the original TBI is used to incorporate the contribution of termites in driving litter mass loss. By characterising both termite- and microbial-driven decomposition, the extended TBI will provide a comprehensive understanding of decomposition and its drivers in termite-rich ecosystems, and permit global comparisons. [ABSTRACT FROM AUTHOR]