Termite Nests Research Articles

Incidence of epigeal nest-building termites in Brachiaria pastures in the Cerrado

This study aimed to determine the number of termite epigeal nests and estimate the soil turning capacity of termites in cultivated pasture environments and in a native vegetation area. Surveys were conducted in four areas: three pasture areas and a Cerrado area, measuring 5 ha each. For each nest, the height, the perimeter and diameter at the base were measured. The volume of each mound was calculated. Turned soil was determined by randomly sampling 30 termite mounds in a pasture area for bulk density determinations. The mean number of termite mounds per ha was 408; the highest number of termite nests (672 per ha) was found in the 10-year-old pasture. In terms of termite mound density, there was no difference between the Cerrado, 3-year-old pasture, and 3-year-old intercropped pasture treatments. The total area occupied by termite nests ranged from 0.4 to 1.0%. The mean bulk density of the nest materials was 1.05 g cm-3. The total nests volume ranged from 4 to 11 m3 ha-1. The total mass of the soil turned by the termites ranged from 3.4 to 13.4 ton. ha-1.

Xylaria coprinicola, a new species that antagonizes cultivation of Coprinus comatus in China

The species known in China as the chicken-claw fungus is described as a new species, Xylaria coprinicola. This species is known as an antagonist of cultivation of the edible mushroom Coprinus comatus. Stromata of X. coprinicola are cylindrical, terminate in a sterile apex and arise in fascicles from a relative large submerged base; perithecia are immersed and have conspicuously conical ostiolar openings; ascospores are minute. Phylogenetic analyses based on combined partial sequences of rpb2, β-tub and α-act genes showed that X. coprinicola is closely related to those Xylaria species exclusively associated with termite nests.

Rich Microbial Community Associated with the Nest Material ofReticulitermes flavipes(Isoptera: Rhinotermitidae)

ment that can contain a rich community of micro organisms and the nest material can be a site of enhanced microbial activity (Holt & Lepage 2000). By using feces and saliva as building mate rials for nest construction and gallery systems, termites can alter the qualitative and quantita tive composition of the resident soil microorgan ism community from adjacent soils (Jouquet et al. 2005). Keya et al. (1982) suggested that a signifi cant part of the altered microorganism commu nity was mostly composed of cellulose decompos ers, but function and origin of the microbial com munity associated with termite nests remains un clear. In this report we evaluate whether subterranean termites have the ability to import various microorganisms from distant soils or from their own gut microbial community into a microorganism-free soil environment. In Chouvenc et al. (2008), we investigated the survivorship of groups of 960 Reticulitermes flavi pes (Kollar) from large two-dimensional arenas filled with sterile sand (washed with 70% ethanol, rinsed with sterile deionized water and oven dried at 60°C for 24 h). At the end of the 90-d ex periment, 4 arenas from 2 different termite colo nies were dismantled to obtain 2 types of nest ma terial: (1) gallery material including sand mixed with termite fecal material from termites galler ies, and (2) non-gallery material including undis turbed sand (not tunneled by the termite) at least 3 cm away from any termite gallery (Fig. 1). A to tal of 12 soil samples per arena (10 g per sample) including 6 samples for each type of nest material were collected. In order to estimate the microbial

Bats

Bats

Do roost-excavating bats have stronger skulls?

In addition to feeding, many vertebrates use their skulls for other functions that are highly relevant to fitness. One such function is roost excavation by the bat Lophostoma silvicolum. Males of this species use their canines to create cavities inside active termite nests, which are significantly harder than the prey they eat. Here we investigate whether the skull of L. silvicolum is specialized for roost excavation relative to the ecologically similar species Tonatia saurophila and Micronycteris hirsuta, which do not excavate roosts. We conducted a finite element analysis that simulated roost excavating and feeding behaviours. These analyses were informed by our observations of feeding and roost-excavating behaviours, bite force, and dissections of the cranial musculature of the three bat species. During the simulation of roost excavation (bilateral canine biting), our data indicate that most regions of the skull of L. silvicolum exhibit less stress than those of T. saurophila and M. hirsuta; however, the latter exhibited the lowest peak stress at the zygomatic arches. During loads that simulate feeding (bilateral molar biting), the three species exhibit similar stress levels. It is not clear whether L. silvicolum has a skull shape that is stronger under the loads imposed by excavation, but it does exhibit relatively higher bilateral canine bite forces that are generated via relatively larger temporalis muscles. Based on the muscle data, our study suggests that the feeding apparatus of mammals can exhibit performance and morphological adaptations to functions other than feeding. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102, 1–10.

TERMITE SPECIES RICHNESS ON THE CAMPUS OF UNIVERSITAS INDONESIA, DEPOK

Termites are a group of invertebrates abundant in forested habitats. In this study, we conduct an inventory and spatial analysis of the termite fauna of the UI campus. The survey records the presence of six termite species (Coptotermes curvignathus, Schedorhinotermes javanicus, Macrotermes gilvus, Microtermes insperatus, Odontotermes grandiceps, and Odontotermes javanicus), most of which had been reported by previous studies. The spatial analysis of termite nest distribution suggests a random scattering of termite nests in the UI campus. Keywords : faunal inventory, termites, spatial distribution, UI campus

Genetic diversity of termite-egg mimicking fungi “termite balls” within the nests of termites

Antagonistic or mutualistic interactions between insects and fungi are well-known, and the mutualistic interactions of fungus-growing ants, fungus-growing termites, and fungus-gardening beetles with their respective fungal mutualists are model examples of coevolution. However, our understanding of coevolutionary interactions between insects and fungi has been based on a few model systems. Fungal mimicry of termite eggs is one of the most striking evolutionary consequences of insect–fungus associations. This novel termite–fungus interaction is a good model system to compare with the relatively well-studied systems of fungus-growing ants and termites because termite egg-mimicking fungi are protected in the nests of social insects, as are fungi cultivated by fungus-growing ants and termites. Recently, among systems of fungus-growing ants and termites, much attention has been focused on common factors including monoculture system for the ultimate evolutionary stability of mutualism. We examined the genetic diversity of termite egg-mimicking fungi within host termite nests. RFLP analysis demonstrated that termite nests were often infected by multiple strains of termite egg-mimicking fungi, in contrast to single-strain monocultures in fungus combs of fungus-growing ants and termites. Additionally, phylogenetic analyses indicated the existence of a free-living stage of the termite egg-mimicking fungus as well as frequent long-distance gene flow by spores and subsequent horizontal transmission. Comparisons of these results with previous studies of fungus-growing ants and termites suggest that the level of genetic diversity of fungal symbionts within social insect nests may be important in shaping the outcome of the coevolutionary interaction, despite the fact that the mechanism for achieving genetic diversity varies with the evolutionary histories of the component species.

Apparent Synergy Among Defense Mechanisms in Subterranean Termites (Rhinotermitidae) Against Epizootic Events: Limits and Potential for Biological Control

The use of entomopathogens for biological control of subterranean termites (Rhinotermitidae) has attracted attention in the past four decades, and several laboratory studies have shown promising results with fungal agents. This approach was based on the concept of classical biological control with the use of a virulent agent that can self-replicate in a termite nest and be transmitted among individuals, resulting in an epizootic to kill the entire colony. However, the absence of positive results in field studies challenged the potential of fungal pathogens as a realistic approach for subterranean termite control, and the relationship between fungi and subterranean termites remains poorly understood. A multimodal approach of the currently identified defense mechanisms allowed us to show that subterranean termites have the ability to prevent an epizootic from occurring. The defense mechanisms involved in such resistance are reviewed and documented. Finally, the interactions among three major defense mechanisms (grooming, cellular encapsulation, and gut antifungal activity) were analyzed, and it is suggested that these mechanisms act synergistically to produce an efficient defense against the infection of the fungus at the individual and group level so as to protect the colony from epizootics.

Parallel evolution of termite-egg mimicry by sclerotium-forming fungi in distant termite groups

Among the great diversity of insect–fungus associations, fungal mimicry of termite eggs is a particularly fascinating consequence of evolution. Along with their eggs, Reticulitermes termites often harbour sclerotia of the fungus Fibularhizoctonia sp., called ‘termite balls’, giving the fungus competitor-free habitat within termite nests. The fungus has evolved sophisticated morphological and chemical camouflage to mimic termite eggs. To date, this striking insect–fungus association has been found in eight temperate termite species, but is restricted to the lower termite genera Reticulitermes and Coptotermes. Here, we report the discovery of a novel type of termite ball (‘Z-type’) in the subtropical termite, Nasutitermes takasagoensis. Phylogenetic analysis indicated that the Z-type termite ball is an undescribed Trechisporoid fungus, Trechispora sp., that is phylogenetically distant from Fibularhizoctonia, indicating two independent origins of termite-egg mimicry in sclerotium-forming fungi. Egg protection bioassays using dummy eggs revealed that Reticulitermes speratus and N. takasagoensis differ in egg-size preference. A comparative study of termite ball size and egg-size preference of host termites showed that both fungi evolved a termite ball size that optimized the acceptance of termite balls as a unit investment. Termite-egg mimicry by these fungi offers a model case of parallel evolution. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 531–537.

Two new species of Aleocharinae (Coleoptera, Staphylinidae) found in fungus gardens of Odontotermes termites (Isoptera, Termitidae, Macrotermitinae) in Khao Yai National Park, Thailand

Discoxenus katayamai sp. n. and Odontoxenus thailandicus sp. n. are described from Khao Yai National Park, East Th ailand. Both species were collected from nests of termite of the genus Odontotermes Holmgren, 1912. Th ese are the fi rst records of both genera from Th ailand. Discoxenus katayamai is similar to D. indicus Wasmann, 1904, and O. thailandicus is similar to O. butteri (Wasmann, 1916). Each species is easily distinguished from their congeners by the body size, the number of the setae on the pronotum, elytra and abdomen and other characters discussed below.

Fire management and the nesting of Athene cunicularia (Aves, Strigidae) in grasslands in central Cerrado, Brazil

Fire management is a common practice in several reserves in the Cerrado, but its influences on bird reproduction remain unknown. In addition, the nesting biology of the Burrowing Owl (Athene cunicularia) has been studied in numerous environments, but not in tropical grasslands managed by fire. This study examined the effects of fire management on the nesting biology of A. cunicularia in Emas National Park, State of Goias, central Brazilian Cerrado. We compared the number of breeding pairs and their burrows in October and November 2009 at 15 study sites in grasslands managed by fire (firebreaks) and unmanaged grasslands adjacent to and distant from firebreaks. We visited active burrows two-four times and described the burrow entrances and sentinel sites and counted and observed adults and young. A total of 19 burrows were found at firebreaks. One and two burrows were found in grasslands adjacent to and distant from firebreaks, respectively. For all burrows found, one to three young reached the adult size, being able to fly and/or run in early November. The 22 burrows found were in the ground, associated or not with termite and ant nests. Most (86.4%) burrows had only one entrance. Only three burrows had two or three entrances. Structures used as sentinel perches by adults were mounds in front of the burrow entrances, termite nests, shrubs and trees. Most of these sentinel sites were shorter than 2 m high and located less than 10 m from the burrow entrance. At Emas National Park, firebreaks appear to provide more attractive conditions to the nesting of A. cunicularia than unmanaged grasslands, likely because of the short herbaceous stratum due to frequent burning of firebreaks. This study suggests that fire management provides suitable conditions for the successful reproduction of A. cunicularia in firebreaks at Emas National Park.

The Ceratocanthinae of Ulu Gombak: high species richness at a single site, with descriptions of three new species and an annotated checklist of the Ceratocanthinae of Western Malaysia and Singapore (Coleoptera, Scarabaeoidea, Hybosoridae)

The remarkable species richness of Ceratocanthinae (Coleoptera: Scarabaeoidea: Hybosoridae) found at Ulu Gombak (Selangor, West Malaysia), a secondary rainforest research station, is discussed. Eighteen species have been collected, mainly in nests of termites (Isoptera) and bess beetles (Coleoptera: Passalidae). Among them at least seven are new species, three of them here described: Madrasostes hashimi sp. n., Madrasostes mirificum sp. n., and Pterorthochaetes tsurui sp. n. Four other species (Madrasostes agostii Paulian, Madrasostes clypeale Paulian, Madrasostes depressum Paulian, and Madrasostes simplex Paulian) are recorded for the first time for West Malaysia and three for new states within West Malaysia (Pterorthochaetes insularis Gestro, Madrasostes malayanum Paulian and Madrasostes sculpturatum Paulian). A checklist of the 34 Ceratocanthinae recorded so far from West Malaysia and Singapore is provided with taxonomic, distributional and morphological remarks on some species.

Phosphorus forms in Brazilian termite nests and soils: Relevance of feeding guild and ecosystems

It is well known that termites enrich organic matter in their nests and alter its properties, but their influence on phosphorus forms is less clear. The aim of our study was to quantify and systemize phosphorus forms in different nest parts (outer wall, inner wall, and central part) of termites of varying feeding guilds and soils in seven dominant Brazilian ecosystems. Organic (P o) and inorganic P (P i) were analyzed after sequential extraction of six labile and stable P fractions in samples from the Amazon region (Terra firme, and Várzea and Igapó floodplains), the Pantanal, the Atlantic rain forest (Mata Atlântica), the Cerrado and the Caatinga. In addition, selected alkaline extracts were characterized by means of liquid-state 31P NMR spectroscopy. The central part of termite nests contained between 275 and 1871 mg kg − 1 total P, dominated by P i in nests of soil/wood interface-feeder termites, but with balanced P o and P i contents in nests of wood-feeding termites. All P o fractions, and, in most nests, also labile P i forms were enriched in termite mounds in comparison to soils. The P enrichment was most pronounced in nests of the Terra firme (enrichment factors for labile P i forms and for P o fractions were 1.7–36.5 and 1.1–16.8, respectively), and the Igapó (labile P i: 4.1–34.0; P o: 1.1–25.7) where the total P content of the soil was the lowest with 141 and 171 mg kg − 1 . Nests of wood-feeding termites mainly accumulated highly labile resin-P i (enrichment factor 10.5–36.5) and partially the stable HCl conc-P i fractions, apart from P o, which can be all attributed to the organic food source and food digestion. The soil/wood interface-feeder termites had more variations in their nests, but in general had higher portions of P bonded to minerals. Hence, we conclude that (i) termite activity results in a gross enrichment of labile P forms in the nests, (ii) the P composition in termite nests reflects the major feeding guild, and (iii) the degree of this P enrichment is partly driven by the P stock in the soil.

Coleoptera Larval Fauna Associated with Termite Nests (Isoptera) with Emphasis on the “Bioluminescent Termite Nests” from Central Brazil

Beetle larvae that inhabit termite nests present modifications that allow them to cohabitate with the termites. Some are physogastric and bear special glands and different setae all over their bodies, whereas others are not physogastric. Both kinds of larvae may be termite predators. Some species usually live in the nest cabbage pan, feeding on organic matter, mushrooms, and excrements or eating the nest walls and sometimes causing the nest to be destroyed. Other species live in superficial galleries of the nest and feed on preys that live outside. However, all interactions between these inquilines beetles and their termite hosts are very complex and still little understood. Emphasis was done to the bioluminescent termite nests from Central Brazil and for this reason general aspects of the bioluminescence related to the elaterid fireflies were also given. The adaptations to live in nest environment and functional categories of association of all beetle larvae we have studied, including those not bioluminescent, to termite nests are discussed in this work.

Ant fauna (Hymenoptera, Formicidae) associated to arboreal nests of Nasutitermes spp: (Isoptera, Termitidae) in a cacao plantation in southeastern Bahia, Brazil

Ants are among the most common arthropods that colonize termite nests. The aim of this study was to identify the ant fauna associated to termite nests found in a cacao plantation in the county of Ilhéus, Bahia, Brazil, with emphasis on the fauna that uses the nests as foraging and/or nesting environment. For this purpose, 34 active, decadent and abandoned nests of Nasutitermes corniger, N. ephratae and Nasutitermes sp., with different volumes and degrees of activity, were dissected. A total of 54 ant species, belonging to 23 genera and five subfamilies, was found in the constructions. The active, decadent and abandoned termite nests presented, respectively, six, eight and 48 ant species. Crematogaster acuta and Ectatomma tuberculatum were the most frequent species in the active and decadent nests, respectively, while the most frequent species in the abandoned nests were Solenopsis pollux, Thaumatomyrmex contumax and Thaumatomyrmex sp. Twenty-six ant species had true colonies within the termitaria. The Formicidae species richness in the nests was inversely related to the degree of termite activity in the nests. The occurrence of living, decadent or abandoned termitaria of Nasutitermes spp. in cacao plantations foments the heterogeneity of habitats available in the plantations and favors the maintenance of high diversity of organisms that use obligatory or opportunistically this substrate.

Phylogenetic status of Xylaria subgenus Pseudoxylaria among taxa of the subfamily Xylarioideae (Xylariaceae) and phylogeny of the taxa involved in the subfamily

To infer the phylogenetic relationships of Xylaria species associated with termite nests within the genus Xylaria and among genera of the subfamily Xylarioideae, beta-tubulin, RPB2, and alpha-actin sequences of 131 cultures of 114 species from Xylaria and 11 other genera of the subfamily were analyzed. These 11 genera included Astrocystis, Amphirosellinia, Discoxylaria, Entoleuca, Euepixylon, Kretzschmaria, Nemania, Podosordaria, Poronia, Rosellinia, and Stilbohypoxylon. We showed that Xylaria species were distributed among three major clades, TE, HY, and PO, with clade TE-an equivalent of the subgenus Pseudoxylaria-encompassing exclusively those species associated with termite nests and the other two clades containing those associated with substrates other than termite nests. Xylaria appears to be a paraphyletic genus, with most of the 11 genera submerged within it. Podosordaria and Poronia, which formed a distinct clade, apparently diverged from Xylaria and the other genera early. Species of Entoleuca, Euepixylon, Nemania, and Rosellinia constituted clade NR, a major clade sister to clade PO, while those of Kretzschmaria were inserted within clade HY and those of Astrocystis, Amphirosellinia, Discoxylaria, and Stilbohypoxylon were within clade PO.

GPR detection of several common subsurface voids inside dikes and dams

Ground-penetrating radar (GPR) technique has been used in detecting several common subsurface voids inside dikes and dams in south of China, and the results indicate that GPR can be successfully applied to uncovering termite nests inside dikes and dams, and the technique proves to be advantageous in real-time retrieval of detection data, precise positioning and effect of application being basically not affected by locality and climate, when it is compared to other available methods. GPR is also effective in detecting cracks in the sloping clay core, and proves to pose less impact on the normal operation of the detected hydraulic projects, be more efficient, and capable of retrieving more comprehensive detection data, when compared with the method of artificial observation through holes chiseled out from the ground. Also, GPR is capable of detecting ferralsol in tropical and subtropical regions to some depth, and shows high value of application in detecting some hidden troubles such as caves and settlements with low to moderate depths inside dams in karst regions. Moreover, GPR technique proves to be so capable of detecting carbonate rocks to certain depth and can yield precise results that it can be applied to analysis and discovery of leakage channels inside reservoirs in karst regions.

Roost Making in Bats—Adaptations for Excavating Active Termite Nests

The breadth of an animals’ ecological niche is circumscribed by its morphology, performance, and behavior, 3 factors that can ultimately affect fitness. We investigated potential behavioral and performance adaptations to roost making, a life-history trait associated with high fitness in the insectivorous bat Lophostoma silvicolum. Males of this species use their teeth to excavate roosts in active termite nests, which we found to be much harder than the hardest prey in the bats’ diet (beetles). We compared roost making and feeding behavior in L. silvicolum. We also compared the feeding behavior of L. silvicolum to that of 2 similar species that do not excavate roosts. All 3 species predominantly used bilateral bites centered on the premolar and molar teeth to eat beetles. In contrast, L. silvicolum used mainly bilateral bites involving the incisors and canines for roost excavation. All species generated similar bite forces during biting behaviors associated with feeding, but L. silvicolum generated significantly higher bite forces during biting behaviors used for roost excavation. We found no difference in canine tooth wear between the sexes, but tooth wear was significantly higher in an ecologically similar species that does not excavate roosts. We conclude that the behavior, performance, and possibly morphology of L. silvicolum represent adaptations to roost excavation.

Molecular diversity and host specificity of termite-associated Xylaria

Studies have revealed that some Xylaria species were closely associated with fungus-growing termite nests. However this relationship rarely had been investigated and the host specificity of termite-associated Xylaria was not yet clearly established. Eighteen Xylaria rDNA-ITS sequences were obtained from fungus combs belonging to 11 Macrotermitinae species from eight regions. Low diversity was found between isolates, and nine sequences were retrieved. Termite-associated Xylaria were shown to be monophyletic, with three main clades, all including strains from various termite hosts and geographical localities. This new molecular study shows no species specificity with respect to fungus-growing termites, which suggests that there might be substrate specialization.

Application of Ground Penetrating Radar in Detecting the Hazards and Risks of Termites and Ants in Soil Levees

A ground penetrating radar (GPR) technique was used to detect Formosan subterranean termite (Coptotermes formosanus) and red imported fire ant (Solenopsis invicta) hazards and risks (targets) in a soil levee at the London Avenue Canal in New Orleans, LA. To make this assessment, GPR signal scans were examined for features produced by termite or ant activities and potential sources of food and shelter such as nests, tree roots, and voids (tunnels). The total scanned length of the soil levee was 4,125 m. The average velocity and effective depth of the radar penetration was 0.080 m/ns and 0.61 m, respectively. Four hundred twenty-seven targets were identified. Tree roots (38), voids (31), fire ant nests (209), and metal objects (149) were detected, but no Formosan termite carton nests were identified. The lack of identified termite nests may be related to drowning events at the time to the flood. Based on the target density (TD), the two new floodwall and levee sections that were rebuilt or reinforced after they were destroyed by Hurricane Katrina in 2005 were determined to be at low potential risk from termites and ants. A merging target density (MTD) method indicated a high potential risk near one of the breached sections still remains. Foraging and nesting activity of Formosan subterranean termites and red imported fire ants may be a contributory factor to the levee failure at the London Avenue Canal.