Termite Nests Research Articles

Macro-symbiosis triggered by a defence-reproduction tradeoff in a social insect

Symbiotic associations underlie hierarchical evolutionary transitions being crucial to understanding biological complexity. But which proximate triggers promote the first successful contact between guests and their hosts? We tackle this problem, studying the macro-symbiotic model system comprised by two termite species (Blattodea: Isoptera) cohabiting termitaria as a host and its obligatory inquiline. We tested the hypothesis that ergonomic adjustments in resource allocation force termite colonies to trade current defence for future reproduction, thence easing inquiline infiltration. To do so, we combined mathematical modelling and field bioassays. Initially, we created a dynamic model to inspect colony’s resource allocation as a result of the competition between a physical “defence specialist” caste (soldiers) competing for resources with a reproductive caste (alates) and with a physical resource-gatherer specialist caste (workers). This model differs from Oster & Wilson’s “bang–bang” model by the explicit inclusion of solders as a physical defence specialist. Then, we sought empirical support for the end results of our model (i) censusing the population and (ii) measuring the patrolling efforts by soldiers, in 154 mature field termite colonies along a year-long reproductive season. Finally, we verified in the field whether reproducing termite colonies would be more likely to house inquilines than colonies still not at reproductive stage. Modelling and field results matched closely, supporting our hypothesis. Inquiline termites (Inquilinitermes microcerus) sneaked into nests of host termites (Constrictotermes cyphergaster) as these latter colonies undergone a defence-reproduction tradeoff. As the host colony entered reproduction, their soldier numbers and patrolling waned, enhancing the proneness of infiltration by obligatory inquilines. Our results indicate that defence-reproduction tradeoffs, more than a strategy to optimise resource use, can be important initiators of symbioses by loosening self/non-self discrimination and enhancing tolerance. We speculate that, if changes in the internal stasis of an organism or superorganism can enhance tolerance, it could be invoked to explain why symbioses are frequently enhanced by stress and disturbance.

Antioxidant Activity and Cytotoxicity against Cancer Cell Lines of the Extracts from Novel Xylaria Species Associated with Termite Nests and LC-MS Analysis.

Xylaria species associated with termite nests or soil have been considered rare species in nature and the few which have been reported upon have been found to act as a rich source of bioactive metabolites. This study evaluated 10 ethyl acetate extracts of five new Xylaria species associated with termite nests or soil for their antioxidant activity, and cytotoxicity against different cancer and normal cell lines. DPPH and ABTS radical scavenging activities of the extracts demonstrated strong capacity with low IC50 values. The highest observed activities belonged to X. vinacea SWUF18-2.3 having IC50 values of 0.194 ± 0.031 mg/mL for DPPH assay and 0.020 ± 0.004 mg/mL for ABTS assay. Total phenolic content ranged from 0.826 ± 0.123 to 3.629 ± 0.381 g GAE/g crude extract which correlated with antioxidant activities. The high total phenolic content could contribute to the high antioxidant activities. Cytotoxicity was recorded against A549, HepG2, HeLa and PNT2 and resulted in broad spectrum to specific activity depending on the cell lines. The highest activities were observed with X. subintraflava SWUF16-11.1 which resulted in 11.15 ± 0.32 to 13.17 ± 2.37% cell viability at a concentration of 100 µg/mL. Moreover, LC-MS fingerprints indicated over 61 peaks from all isolates. There were 18 identified and 43 unidentified compounds compared to mass databases. The identified compounds were from various groups of diterpenoids, diterpenes, cytochalasin, flavones, flavonoids, polyphenols, steroids and derivatives, triterpenoids and tropones. These results indicate that Xylaria spp. has abundant secondary metabolites that could be further explored for their therapeutic properties.

Bioprospecting of insect nest associated actinobacteria with special reference to antimicrobial and anti HIV activity

The present study attempted to explore actinobacteria from different insect nest samples for antimicrobial activity. Totally, 43 actinobacterial colonies were recovered from ant nest, termite nest, wasp nest and blanket worm nest samples by adopting standard spread plate method. Screening of antimicrobial properties of actinobacterial strains was determined by agar plug method. Two actinobacterial strains AN1 and AN5 showed promising activity (14-18 mm inhibition) against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, carbapenem resistant Klebsiella pneumoniae and Mycobacterium smegmatis. Both the strains produced antimicrobial compound earlier on ISP2 agar when compared to ISP2 broth. Crude extracts from the strains AN1 and AN5 were produced by adopting agar surface fermentation and extracted using ethyl acetate. Based on the studied phenotypic characteristics, actinobacterial strains AN1 and AN5 isolated from ant nest were identified as Streptomyces sp. In addition to antimicrobial activity, extracts also showed anti-HIV activity. This study concluded that insect nest is a promising source for bioactive actinobacteria. Two potential Streptomyces sp. AN1 and AN5 isolated from ant nest will be promising sources for antimicrobial metabolites against drug resistant bacteria, retrovirus and mycobacterial pathogens.

Twelve New Taxa of Xylaria Associated with Termite Nests and Soil from Northeast Thailand

Simple SummaryXylaria species are known for their medicinal value and production of a variety of bioactive compounds. They usually grow on rotten wood, fallen leaves, seeds, and fruits. Some species can be found growing on soil or associated with termite nests, which belong to subgenus Pseudoxylaria. They share with other Xylaria species a suite of morphological characteristics, including conspicuous or massive upright stromata with a light-coloured interior, a longer than wide ascal apical ring, bluing in an iodine reagent, and brown unicellular ascospores possessing a germ slit. In Thailand, there are only limited reports on Xylaria diversity and taxonomy, especially on species associated with termite nests. In the present study, we describe 12 new Xylaria taxa and report two species closely resembling known species from termite nests or soil. Their morphological and cultural characteristics are described and illustrated, and their nucleotide sequences of ITS rDNA, alpha-actin, and beta-tubulin genes were obtained. Phylogenetic inference based on these sequences confirmed that all taxa analyzed belong to subgenus Pseudoxylaria and differ from all other species with sequences available in public databases. Our study is the first to report on the novel Xylaria species associated with termite nests or growing on soil in Thailand. Subgenus Pseudoxylaria is likely highly diverse in the country.The diversity of Xylaria species associated with termite nests in northeast Thailand was investigated. Among the 14 taxa included in this study, 11 species and one variety were described as new, and another two species resemble the existing taxa, X. escharoidea and X. nigripes. The newly described taxa are X. chaiyaphumensis, X. conica, X. fulvescens, X. ischnostroma, X. margaretae, X. minima, X. reinkingii var. microspora, X. siamensis, X. sihanonthii, X. subintraflava, X. thienhirunae, and X. vinacea. Their morphological and cultural characteristics are described and illustrated, and their ITS, α-actin and β-tubulin sequences were analysed. A dichotomous key to the 17 species of Xylaria occurring in Thailand is provided.

A review of micromorphological studies of ant and termite's epigean nests located in neotropical soils of Argentina

This publication brings an integral revision about the micromorphology of ant and termite's nests located in neotropical soils. The building materials, wall microstructures, wall coatings, and building techniques are comparatively addressed, and illustrated with new photographic material. The soil nests were assigned to termites Termes saltans, Cortaritermes fulviceps, Cornitermes cumulans, and ants Atta vollenweideri, Camponotus punctulatus, Solenopsis sp, and Acromyrmex fracticornis. These species construct epigean structures, such as mounds and turrets in frequently flooded Mollisols, Ultisols, Alfisols and Entisols of the northern east region of Argentina. The building materials, i.e. soil components, plant fragments, and feces, were distributed and assembled in the nest walls forming characteristics micromorphological features, showing distinct differences with the adjacent soil micromorphology. Termites constructed very hard mounds with compact microstructures composed of soil pellets and grains closely assembled and cemented with feces, showing only thin fissures and very small vughs in their external walls. Interiorly, the walls of growing termite mounds displayed porous microstructures and a distinct parallel arrangement of organic laminae in the hive. Mounds and turrets of ants were constructed with humid soil pellets, firmly adhered without any kind of cement, forming spongy microstructures with mamillated and star-shaped vughs. This porous structure alternated with massive and crack structures, resulting from the breakdown of the wall aggregation by the percolated rain. Many species of ants and termites lined the mound and turret's galleries with feces or fine soil material. An active reorganization of the building materials over time was demonstrated in growing colonies of C. cumulans by means micromorphological analysis of young and mature nests. Likewise, removal of building materials and microstructures was also recorded in turrets of A. vollenweideri constructed in the laboratory with different building materials that were offered consecutively. In addition, the effect of rains on the removal of the pelletal aggregation was experimentally demonstrated. The building technique of turrets of A. fracticornis was revealed in field experiments, recording over time the intermeshing of plant fragments around the nest opening, and its simultaneous cementation with soil pellets.

Diagnóstico da relação de degradação de solo e planta em área de cultivo de Eucalyptus urophylla com a presença de térmitas e formigas

Térmitas e formigas são agentes bióticos com alto nível de diversificação, indicando degradação do solo e deficiência nutricional do mesmo. Com os danos causados por eles, no solo e em plantas de eucalipto, faz-se necessário o controle dessas pragas, de maneira que, para o sucesso da aplicação do manejo integrado de pragas, a avaliação populacional desses indivíduos é fundamental, sendo imprescindível saber como eles se distribuem no campo. Dessa forma, objetivou-se investigar a dinâmica de distribuição espacial de ninhos de formigas e termitas em uma área de floresta plantada de eucalipto, bem como estudar o impacto causado por essas pragas no solo e na planta. Na avaliação dos atributos no plantio de Eucalyptus urophylla foram cinco: (1) o número de árvores mortas, (2) número de formigueiro e (3) número de ninhos de térmitas, (4) área dos formigueiros e (5) área dos ninhos de térmitas. Para os atributos de área de ninhos de formiga e térmitas foi coletado de 3 a 5 amostras das áreas, em seguida realizou a média, a fim de corresponder a cada ponto georreferenciado. Houve uma distribuição irregular dos ninhos de formigas e de térmitas pela área de estudo, atenuando a invasão do capim, principalmente em locais com maior número de ninhos de formigas, recomendando a manutenção deste povoamento em função destes agentes bióticos na área.

Production of extracellular enzymes by a termite‐nest‐related Bacillus siamensisYC‐9 in solid‐state fermentation on agricultural by‐products

AbstractA Bacillus siamensis YC‐9 strain was isolated from termite nest. The strain was used to produce several important industrial enzymes by utilizing different agricultural by‐products with solid‐state fermentation (SSF). It was observed that most of the substrates that were studied were strongly positively affected by alkaline treatment for the production of enzymes. The highest yields for protease, α‐amylase, and cellulase were 82.87, 42.81, and 1.54 IU g−1, achieved on alkaline‐treated corn pericarp, rice bran, and wheat bran respectively. However, untreated soybean meal was the best choice for the secretion of pectinases (66.65 IU g−1). In general, ultrasonic pretreatment was more effective than microwave treatment and it promoted the production of proteases on soybean meal, sunflower meal, and wheat bran. The findings of the present study will provide some theoretical basis for enzyme production in the future. © 2021 Society of Industrial Chemistry and John Wiley & Sons Ltd.

Сравнительное исследование проницаемости грунтовых прослоек из смеси глины и материала термитников Macrotermes gilvus Hagen и бентонита

The liner has a role as a sealing or waterproof layer that was made to prevent water to be absorbed by the soil. A good liner is made within the minimum hydraulic conductivity (k) within the requirements of 1.0E-07 cm/s. This study was conducted to determine the extent of the difference between hydraulic conductivity (k) bentonite and termite nest (Macrotermes gilvus Hagen) as one of the materials that have the potential to obtain the small value of hydraulic conductivity (k). This research was conducted by examining the effect of hydraulic conductivity (k) value on the percentage of additives, such as bentonite and termite nest material (M. gilvus Hagen), and then compared the hydraulic conductivity (k) values of those two materials. The variations in the additive content percentage are 5%, 15%, and 30% with laterite as a base material. Based on the results of the falling head test at a minimum density of 95% γdmax, the smallest hydraulic conductivity (k) value was obtained by bentonite with 30% mixed percentage level of 6.9390E-08 cm/s and the smallest hydraulic conductivity (k) value of termite nests was 1.2646E-07 cm/s with the content percentage of 5% mixture.

DIFFUSE TERMITINAE NESTS SHED LIGHT ON THE AFFINITIES OF LAETOLICHNUS KWEKAI (KRAUSICHNIDAE)

ABSTRACT The insect trace fossil Laetolichnus kwekai, which is composed of a small chamber extending to slender cylinders at each end, was tentatively included in the ichnofamily Krausichnidae as termite nests. New evidence presented here provides information to validate these inferences. A more complex structure formed by interconnected Laetolichnus was recently found in the same Pliocene deposits (Laetoli, Tanzania) as the isolated specimens reported previously. Our study confirms inclusion of Laetolichnus in Krausichnidae and supports the inference that it represents a nest of a social insect. Neoichnological field studies in the coastal dunes of Buenos Aires Province, Argentina, were undertaken to refine further the nature of these affinities. Survey of the dune surface revealed abundant loose fragments of termite nests of a size and shape comparable to that of L. kwekai. The fragile nests constructed by Onkotermes brevicorniger, which are described here in detail for the first time, enable us to interpret the fossil structures. They consist of connected chambers similar to the interconnected Laetolichnus. These were frequently exposed and broken by wind action resulting in loose fragments similar to the isolated Laetolichnus. The Celliforma ichnofacies represented at Laetoli, which contains L. kwekai, indicates arid or semiarid shrublands and woodlands. The distribution of O. brevicorniger also corresponds to arid and semiarid shrublands and dry woodlands of Argentina. Although the African termite producer of L. kwekai and the South American Onkotermes would be phylogenetically unrelated, the analogous structures probably reflect convergent nesting behaviors as an adaptation to similar arid to semiarid environmental conditions.

New faunistic and taxonomic data on oribatid mites (Acari, Oribatida) inhabiting soil and termite nests in the Golden Gate Highlands National Park (eastern South Africa)

ABSTRACT The present study is based on oribatid mite material collected from soil and nests of the termite, Trinervitermes trinervoides of the Golden Gate Highlands National Park in South Africa. A list of identified taxa, including 49 species, belonging to 41 genera and 24 families, is presented; of these, 13 species, eight genera and two families are found in South Africa for the first time. The faunistic comparison of mites from soil and termite nests showed higher abundance and species richness in soil than in the nests. Soil samples contain dominant species Oppiella nova, Tectocepheus velatus sarekensis, Africoribates pilosus, Afroleius lucidus and Scheloribates elsi versus Ausoribula bloemfonteinensis and Coetzeella navalensis in termite nests. One new species, Urubambates ueckermanni sp. nov. (Scheloribatidae) is described as differing from all known species of the genus by the presence of monodactylous legs. http://www.zoobank.org/urn:lsid:zoobank.org:pub:48FD196B-5FED-43AC-AB1E-1F3A3E0C2C78

Inventory of fungi from termite nests at Gunung Leuser National Park, northern Sumatra

Fungi and termite coexisted each other and have diverse symbiotic relationship in tropical forest. This research aims to determine the fungus found on termite nests in Suaq Balimbing Research Station so it can be used that as initial information in developing environmentally friendly termite control. The method used for collecting samples of fungus is a Standarized Sampling Protocol and for identification used slide culture method. The results showed that 5 of 12 termites nest are invaded by fungi. Based on macroscopic and microscopic observation, fungus species that obtained from termite nests are 2 species, namely: Penicillium sp.1, Trichoderma sp. 1

Isolation and Characterization of Poly-(<i>R</i>)-3-hydroxybutyrate Produced by <i>Bacillus thuringiensis</i> TH-01

Poly-(R)-3-hydroxybutyrate (PHB) is a biopolymer that can be synthesized by several microorganisms such as bacteria, yeast, and fungi as secondary metabolites. PHB is produced by bacteria in a medium containing a limited amount of key nutrients such as nitrogen, phosphorus, and magnesium but rich in carbon sources. PHB is a biodegradable plastic that has many applications in the medical and industrial fields. This study aimed to isolate and characterize a biopolymer produced by a bacterium strain isolated from a termite nest in India that was identified by 16S rRNA method as Bacillus thuringiensis TH-01. The biopolymer was produced by growing the bacteria in a high medium overnight at 37 °C in a shaking incubator at 150 rpm, and the resulting biopolymer was extracted with a mixture of chloroform–NaOCl (1:1). The efficiency of biopolymer production was about 10.545% ± 26.125%. Fourier transform infrared analysis gave prominent absorption peaks at 3400 cm−1 (stretching of O–H), 2900 cm−1 (stretching of C–H), 1700 cm−1 (stretching of C=O), 1280 cm−1 (symmetric deformation of C–H), and 1050 cm−1 (stretching of C−O), confirming that the biopolymer is PHB. The thermal stability of PHB granules as was determined by thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC) showed that the decomposition temperature and of the polymer were 271.6–310.0 °C and 7.48 J/g respectively, and its crystallinity was about 5.12%.

Self-organized biotectonics of termite nests

The termite nest is one of the architectural wonders of the living world, built by the collective action of workers in a colony. Each nest has several characteristic structural motifs that allow for efficient ventilation, cooling, and traversal. We use tomography to quantify the nest architecture of the African termite Apicotermes lamani, consisting of regularly spaced floors connected by scattered linear and helicoidal ramps. To understand how these elaborate structures are built and arranged, we formulate a minimal model for the spatiotemporal evolution of three hydrodynamic fields-mud, termites, and pheromones-linking environmental physics to collective building behavior using simple local rules based on experimental observations. We find that floors and ramps emerge as solutions of the governing equations, with statistics consistent with observations of A. lamani nests. Our study demonstrates how a local self-reinforcing biotectonic scheme is capable of generating an architecture that is simultaneously adaptable and functional, and likely to be relevant for a range of other animal-built structures.

Reduced Environmental Microbial Diversity on the Cuticle and in the Galleries of a Subterranean Termite Compared to Surrounding Soil.

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.

Do arboreal termite nests increase mortality in Mauritia flexuosa L. f. (Arecaceae) during wildfires?

ABSTRACT Moriche palm (Mauritia flexuosa Linn f. [Arecaceae]) is a dominant species in the savanna margins of the Caribbean island of Trinidad. The savanna margins are frequently subjected to fires and the moriche palm, like many palm species, is adapted to cope with a degree of fire damage. These palms also frequently host large termite nests that tend to burn during fires, which causes further damage to the palm stems. This paper explores the possibility that the combination of termite nests and frequent fires can increase tree mortality. Two post-fire surveys were conducted to record, evidence of fire exposure, fire damage to termite nests and fire damage to palm stems. In both surveys, the majority of palms with termite nests suffered fire damage to their stems, while none of the termite-free palms showed damage. Furthermore, a comparison of nest size and damage to the bark showed stems with larger nests had significantly more damage than those with smaller or no nests. The results suggest that the presence of termite nests increases the extent of fire damage to palm trunks by providing a point of combustion that focuses flames on the already compromised stem tissue. Long-term studies are warranted to investigate the impact of repeated fires on wild arborescent palm populations.

Termite nests in eolian backshore settings: An unusual record throughout the Quaternary in the Neotropical realm

Termite nests in eolian backshore settings: An unusual record throughout the Quaternary in the Neotropical realm

Multipartite symbioses in fungus-growing termites (Blattodea: Termitidae, Macrotermitinae) for the degradation of lignocellulose.

Fungus-growing termites are among the most successful herbivorous animals and improve crop productivity and soil fertility. A range of symbiotic organisms can be found inside their nests. However, interactions of termites with these symbionts are poorly understood. This review provides detailed information on the role of multipartite symbioses (between termitophiles, termites, fungi, and bacteria) in fungus-growing termites for lignocellulose degradation. The specific functions of each component in the symbiotic system are also discussed. Based on previous studies, we argue that the enzymatic contribution from the host, fungus, and bacteria greatly facilitates the decomposition of complex polysaccharide plant materials. The host-termitophile interaction protects the termite nest from natural enemies and maintains the stability of the microenvironment inside the colony.

An interesting case of polystyrene consumption by <em>Reticulitermes lucifugus</em> (Blattodea: Neoisoptera, Rhinotermitidae)

A colony of Reticulitermes lucifugus from Apulia (SE Italian Peninsula) was recently observed to have partially consumed some polystyrene panels applied on a wall, and used like seat for termite nest. Further observations could allow to better understand if this colony is just able to physically consume and chew this plastic material, releasing it chemically intact after the passage throughout the termites’ digestive system, or if their microbiome could allow the insects to at least partially metabolize and degrade the ingested polystyrene fragments, as recently observed in a few other insects.

High-Throughput Cultivation for the Selective Isolation of Acidobacteria From Termite Nests.

Microbial communities in the immediate environment of socialized invertebrates can help to suppress pathogens, in part by synthesizing bioactive natural products. Here we characterized the core microbiomes of three termite species (genus Coptotermes) and their nest material to gain more insight into the diversity of termite-associated bacteria. Sampling a healthy termite colony over time implicated a consolidated and highly stable microbiome, pointing toward the fact that beneficial bacterial phyla play a major role in termite fitness. In contrast, there was a significant shift in the composition of the core microbiome in one nest during a fungal infection, affecting the abundance of well-characterized Streptomyces species (phylum Actinobacteria) as well as less-studied bacterial phyla such as Acidobacteria. High-throughput cultivation in microplates was implemented to isolate and identify these less-studied bacterial phylogenetic group. Amplicon sequencing confirmed that our method maintained the bacterial diversity of the environmental samples, enabling the isolation of novel Acidobacteriaceae and expanding the list of cultivated species to include two strains that may define new species within the genera Terracidiphilus and Acidobacterium.

Do Termitaria Indicate the Presence of Groundwater? A Case Study of Hydrogeophysical Investigation on a Land Parcel with Termite Activity.

Termite nests have long been suggested to be good indicators of groundwater but only a few studies are available to demonstrate the relationship between the two. This study therefore aims at investigating the most favourable spots for locating groundwater structures on a small parcel of land with conspicuous termite activity. To achieve this, geophysical soundings using the renowned vertical electrical sounding (VES) technique was carried out on the gridded study area. A total of nine VESs with one at the foot of a termitarium were conducted. The VES results were interpreted and assessed via two different techniques: (1) physical evaluation as performed by drillers in the field and (2) integration of primary and secondary geoelectrical parameters in a geographic information system (GIS). The result of the physical evaluation indicated a clear case of subjectivity in the interpretation but was consistent with the choice of VES points 1 and 6 (termitarium location) as being the most prospective points to be considered for drilling. Similarly, the integration of the geoelectrical parameters led to the mapping of the most prospective groundwater portion of the study area with the termitarium chiefly in the center of the most suitable region. This shows that termitaria are valuable landscape features that can be employed as biomarkers in the search of groundwater.