This study describes a new subspecies of Cicindela limbata Say, C. l. nogahabarensis, from the Nogahabara Sand Dunes of the Koyukuk National Wildlife Refuge, Alaska, on the basis of its distinct maculation pattern and results of mitochondrial DNA (mtDNA) analysis. The maculation pattern of this new subspecies is most similar to and overlaps slightly with that of C. l. labradorensis Johnson from Newfoundland, the subspecies from which it is most distant geographically. Results of the analysis of 1,181 bp of mtDNA (partial cob and nad1-rrnL regions) revealed unique haplotypes supporting C. l. nogahabarensis as a distinct taxon. Geographic clade analysis revealed significant patterns of nonrandom haplotype distribution consistent with postglacial geographic isolation between C. l. nogahabarensis and all other C. limbata. Strong support for the monophyly of C. l. nogahabarensis was retrieved using various tree construction methods. Parsimony analysis and Bayesian methods recovered topologies that placed C. l. nogahabarensis and C. l. labradorensis within a group including all other C. limbata and two other species of the martima group. Under the phylogenetic species concept, unique haplotypes diagnose C. l. nogahabarensis as a separate taxon from topotypical C. limbata. Likewise, the population of C. l. labradorensis that was once thought to be an accidental introduction also was recovered as diagnosably distinct from C. l. limbata. This is the first description of a tiger beetle endemic to Alaska, and both groups demonstrate the occurrence of clearly divergent groups of beetles even in recently glaciated areas.

Two new species Dromiciocoptes marmosops sp. n. and Dromiciocoptes caenolestes sp. n., of the subfamily Dromiciocoptinae (Acari: Myocoptidae), are described from Marmosops parvidens Tate (Didelphimorphia: Didelphidae) from Peru and Caenolestes fuliginosus (Tomes) (Pauctituberculata: Caenolestidae) from Ecuador, respectively. Dromiciocoptes has been included in a monobasic subfamily in the Myocoptidae on the basis of female and nymph legs III and IV of being modified for clasping the hair of the host. Observations on the actual structure of these appendages, however, indicate that the mode of hair clasping is fundamentally different than in other myocoptids. The structure of the male legs IV of Dromiciocoptinae and Myocoptinae are also different. Additional diagnostic characters of the subfamily Dromiciocoptinae in both sexes are the enlarged propodonotal and hysteronotal shields; indistinct openings of the opisthonotal glands; reduced pretarsi II; retrorse spurs on coxal fields I–IV; absence of setae vi, c3, famulus e, and one pair of genital papillae; presence of setae sIII; and a pair of antiaxial projections on femora I and II. Synapomorphies uniting these two subfamilies include body shape, separate apodemes I, apical position of tarsus I solenidia ω1 and ω3, scales on the ventral surface of the female opisthosoma (in only some myocoptines), and bilobed male opisthosoma. None of these states are unique among the parasitic Psoroptidia, indicating that the monophyly of the family is weakly supported.

The gall midge Obolodiplosis robiniae (Haldeman) (Diptera Cecidomyiidae), originating from North America and damaging to black locust (Robinia pseudoacacia L.), was detected for the first time in Europe (northern Italy) in 2003. In the subsequent years, the distribution of this O. robiniae in Europe has rapidly expanded and severe symptoms on plants were observed in a number of geographic areas. In Italy, O. robiniae populations are affected by various natural enemies, in particular by a parasitoid in the family Platygastridae. The species involved in parasitism, Platygaster robiniae, is described in this article.

A new genus Dimocarpomyia belonging to the subtribe Asphondyliina (Diptera: Cecidomyiidae: Asphondyliini) is erected for Dimocarpomyia folicola Tokuda & Yukawa, a new species to science. Morphological features of the male, female, full-grown larva, and pupa are described. The gall midge induces obovoid galls on the lower surface of leaves of longan, Dimocarpus longan (Sapindaceae), in Thailand.

The genus Xestocoris Van Duzee is reported from Mexico for the first time, and three new species, X. adustus (Guerrero, Morelos, Nayarit, and Puebla), X. clavatus (Chiapas, Guerrero, Michoacan, and Oaxaca), and X. punctatus (Chiapas), are described. Two species, X. collinus described from Guatemala and Panama, and X. tibialis from the United States, are newly recorded for Mexico. Habitus, illustrations, and drawings of the male genitalia are provided, and a key to the known Xestocoris species is presented.

The adult and third instar of a new genus and new species of leucochrysine green lacewings, Santocellus atlanticis gen. et sp. nov., are described from Brazil’s Atlantic Forest. The first instar of Santocellus riodoce (Tauber) comb. nov. (formerly Leucochrysa riodoce) also is described. These two species share a distinguishing suite of adult and larval features: wings with dark (sometimes pustulate) markings; male with an elongate, cylindrical mediuncus and stiff membrane below; female with round, doughnut-shaped spermatheca having a shallow invagination and a sail-shaped velum that extends anteriorly; larvae with discrete, longitudinal head markings, short mandibles, broad labial palpi, and short, stubby, ventrally projecting terminal palpomeres. With this new genus (Santocellus gen. nov.), the number of genera in the tribe Leucochrysini increases to seven; Santocellus gen. nov. includes three described species: S. atlanticis sp. nov. and S. riodoce comb. nov., both from Brazil, and Santocellus bullata (Tauber) comb. nov., from Peru.

RESUMO O adulto e a larva de terceiro instar de novo gênero e nova espécie de crisopídeo leucocrisíneo da Mata Atlântica do Brasil, Santocellus atlanticis gen. et sp. nov., são descritos. O primeiro instar de Santocellus riodoce (Tauber) comb. nov. (anteriormente Leucochrysa riodoce) também é descrito. Estas duas espécies compartilham um conjunto distintivo de características tanto do adulto como da larva: asas com manchas escuras (algumas vezes pustulosas); macho com mediuncus cilíndrico, alongado, com membrana rígida ventralmente; fêmea com espermateca arredondada, em forma de rosca, com uma invaginação rasa e com o velum grande, em forma de vela, estendendo-se anteriormente; larvas com manchas cefálicas separadas, alongadas longitudinalmente mandíbulas curtas, palpos labiais largos com palpômeros terminais curtos, grossos, projetando-se ventralmente. Com este novo gênero (Santocellus gen. nov.), o número de gêneros da tribo Leucochrysini aumenta para sete; Santocellus gen. nov. inclui três espécies descritas: S. atlanticis sp. nov. e S. riodoce comb. nov., ambas do Brasil, e Santocellus bullata (Tauber) comb. nov., do Peru.

Clusia Haliday, 1839 (Clusiidae: Clusiinae) is redefined, with Amuroclusia Mamaev, 1987 syn. nov. and Paraclusia Czerny, 1903 syn. nov. included as junior synonyms. Melanoclusia gen. nov. is described for the new Malaysian species M. bivibrissa spec. nov. and treated as the sister group to Clusia.

Bactrocera invadens Drew, Tsuruta & White (Diptera: Tephritidae), an invasive fruit fly species of Asian origin, was detected in Kenya in 2003, and is now well established in several parts of the country. We assessed the host range of this major quarantine pest in Kenya by collecting a wide range of cultivated and wild host plants from December 2004 to April 2006. Fruit were collected from 90 plant species representing 40 families from the Coast, Eastern, and Rift Valley provinces of the country where the fly population had been observed to occur in large numbers and where fruit and vegetable production is predominant. Fourteen plant species, among them cultivated and wild fruiting species, were found to be hosts of B. invadens. Fruit of mango, Mangifera indica L. (Anacardiaceae); banana Musa sp. AAA (Musaceae); and citrus [Citrus limon (L.) Burm.f. (lemon), Citrus reticulata Blanco (tangerine), and Citrus sinensis (sweet orange) (all Rutaceae)], were among the cultivated species heavily infested by B. invadens. Marula Sclerocarya birrea (A.Rich) Hochst. (Anacardiaceae) and Terminalia catappa L. (Combretaceae) were found to be the most infested noncultivated plants. These wild plants evidently ensure that sufficient reproductive bases exist for B. invadens during the off-season when the cultivated hosts are not in fruiting. In laboratory host preference studies, mango and banana were found to be the most preferred host plants among the nine cultivated plant species tested.

There is increasing evidence that Aphis glycines Matsumara (Hemiptera: Aphididae) populations are negatively impacted by endemic natural enemies within North America. In Iowa, surveys of natural enemies in soybean, Glycine max (L.) Merr., conducted before the arrival of A. glycines revealed a number of species that may contribute to their mortality. We used several sampling methods to determine the diversity of the natural enemy community in Iowa soybean since the arrival of A. glycines. Natural enemies were collected using field-counts (in situ sampling), destructive counts, sweep-net sampling, and yellow-sticky cards. When predaceous arthropods were combined across all sampling methods, six orders were identified, including nine families and 13 genera. In comparison with a similar study conducted 26 yr ago, we observed fewer native coccinellids with the most abundant being the exotics Harmonia axyridis (Pallas) and Coccinella septempunctata L. (Coleoptera: Coccinellidae). Combining all foliar-based sampling methods reveals a community of four aphidophagous taxa that account for >94% of the total captured: Toxomerus spp., H. axyridis, Orius insidiosus (Say), and Chrysoperla spp. In both years, destructive counts collected fewer species with more found using field-counts, sweep-net, and yellow-sticky cards. Sweep-net and yellow-sticky cards collected more agile life-stages and species as expected from sampling methods that rely on the insects’ activity/density to be effective. Our data suggest absolute methods such as destructive and field-counts may underestimate the contribution of mobile predators on A. glycines mortality.

We applied 14 insect development models, both deterministic and distributed, to describe Russian wheat aphid, Diuraphis noxia (Mordvilko) (Hemiptera: Aphididae), development and phenology. The Russian wheat aphid developmental data were from a laboratory experiment of 25 combinatorial treatments of five temperatures and five spring barley, Hordeum vulgare L., plant growth stages. The developmental times of 1,800 individual Russian wheat aphids at various stages were recorded in the experiment. We first compared 11 deterministic development models and discussed some problems associated with the fitting of these models. Not all nonlinear models could be fitted to every Russian wheat aphid stage. The results show that Stinner’s model overall best fit Russian wheat aphid developmental rate data, as judged by mean square error (MSE) and successful convergence. However, we observed a seemingly inescapable dilemma: when one introduces more complex nonlinear models to increase the descriptive power of models (with the hope that model parameters have some biological meanings), the more difficult it is to successfully fit the model. Even if the model is fitted successfully, the values of the model parameters may well be beyond biologically meaningful ranges. Furthermore, we believe that a potentially more serious trap associated with complex nonlinear model is the extreme low tolerance of model parameters. Our results show that the extreme low tolerance associated with the parameter estimate may occur even if the MSE of model fitting is very small. The second part of our results presented same-shape distribution models for Russian wheat aphid development. Stinner’s model performed well and successfully fitted all 22 data sets, whereas the Weibull distribution and logistic model only succeeded in 17 and six of 22 data sets, respectively. Finally, Population Model Design System software was used to simulate Russian wheat aphid phenology based on the integration of deterministic nonlinear developmental rate models and same-shape distributions models.

Many species of Tachinidae are important parasitoids of herbivorous insects in natural and managed systems; yet, little is known about tachinid diversity and how this diversity is distributed across space and time. Here, pan trap sampling was used to analyze the richness, microhabitat specificity, and seasonal diversity of a tachinid parasitoid community in an oak–mesquite savanna of Southeastern Arizona. Twenty-four traps were set out monthly during the growing season in three different microhabitats (open grassland, woodland understory, and woodland canopy). In total, 79 tachinid species were sampled with an estimated total diversity of 122 species. Most individual traps sampled few species; yet, variation in species composition (β diversity) among sampling dates and microhabitats was high, accounting for 40–70% of the total diversity. Significant intraspecific aggregation was not observed across traps or microhabitats, but it was observed across dates, suggesting that the activity of tachinid species may be associated with host phenology and seasonal periods of precipitation. The β diversity associated with microhabitat and sampling date was significantly greater than expected. Tachinid species diversity was highest in the canopy traps, whereas the open-exposed traps exhibited high abundances of relatively few species, and understory traps sampled few individuals of few species. Most species tended to be sampled where their hosts would be expected to be found, although males were also frequently sampled in microhabitats associated with mate finding. These patterns of diversity and abundance may aid in understanding parasitoid–host associations and variation in rates of parasitism by tachinid flies.

Resistance to insecticides is often linked with fitness costs. Although costs affecting lifetime reproduction in females will have the greatest effect on resistance evolution, fertilization costs in males, through less vigorous mating behavior or less effective sperm in resistant individuals, will slow the spread of resistance. We used a sterile male technique to measure the relative mating competitiveness of Colorado potato beetles, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), resistant or susceptible to imidacloprid. We showed that 5,000 Krad from a cesium-137 source was sufficient to sterilize male beetles. We tested mating competitiveness by placing a single resistant and a single susceptible male beetle with a virgin susceptible female in circular acetate enclosures surrounding potted potato plants, and we observed frequency of mating or mounting with each male and subsequent fertilization success. Resistant males mate just as often as susceptible males during 24-h competitive interactions. Hatch rate was correlated with the proportion of matings or mounts observed with the nonirradiated male, but no effect of the first or last male, nor of resistance on fertilization success was observed, and resistance does not seem to incur a behavioral or sperm-competitive fertilization cost.

Delphastus catalinae (Horn) (Coleoptera: Coccinellidae) is a predator of whiteflies. It is tropical in origin. Whiteflies cause problems in agriculture in both humid and arid environments. A study was conducted to determine any effects of relative humidity on oviposition, hatching, and survival of immature D. catalinae. Comparative tests were conducted among relative humidities of 25, 35, 50, and 85% and between 10 and 85% RH. All tests were conducted at 26°C; hence, vapor pressure deficits ranged from 5.04 to 30.25 mb. The study was conducted using the B-biotype sweetpotato whitefly, Bemisia tabaci (Gennadius), as the host insect, which was reared on collard, Brassica oleracea ssp. acephala de Condolle. Egg hatch and survival to the adult stage were reduced at the lower relative humidities. At 85% RH, 99% of the eggs hatched and ≈90% of the beginning cohort survived to the adult stage. Conversely, ≈85% hatched and ≈60% survived to the adult stage at 25% RH, whereas 50% survived to the adult stage at 10% RH. Eggs required more time to develop at 10% RH (5.3 d) compared with 85% RH (4.1 d); a test was not set up to compare the developmental times for the larval and pupal stages. Weights of male and female D. catalinae were significantly reduced with a reduction in humidity. The results also suggest that density of immature D. catalinae, limited food supply, or both may affect survival and size of the ensuing adults. These results help in the understanding of the ecology of D. catalinae, and they indicate that extremes in ambient moisture can have an impact on the population of this predator.

The species composition and the population dynamics of aphidophagous syrphids (Diptera: Syrphidae) in polyethylene-covered greenhouses of sweet pepper (Capsicum spp.) were studied over a 3-yr period in southeastern Spain. Modified Malaise traps were used to sample the adult flies within the greenhouses, accompanied by direct sampling of syrphid larvae on the sweet pepper plants. Over a 2-yr period, modified Malaise traps also were used to record the movement of syrphids into the greenhouses from the surrounding environment. Additionally, the effect of opening or closing the side walls of the greenhouse (ventilation management) on syrphids was assessed by census techniques. In total, nine species of aphidophagous syrphids were found as larvae, preying on aphids on sweet pepper plants. Three of these species, Eupeodes corollae (F.), Episyrphus balteatus (De Geer), and Sphaerophoria rueppellii (Wiedemann), made up 98% of the larvae collected. There was a temporal succession during the season, attributed to temperature, and variability among years related to drought. S. rueppellii seems to be the most adapted to survival in the high temperatures and dry conditions. Modified Malaise traps proved effective for monitoring adult syrphids in greenhouses, but they also captured species whose larvae are not associated with the aphid colonies in sweet pepper. This indicates that when studying aphidophagous syrphids, sampling of adults by Malaise trap should be accompanied by sampling of larvae. Larger numbers of syrphids were captured outside of the greenhouse than inside. Opening the side walls of greenhouses increased syrphid numbers within it, and this should be considered in pest management regimes.

Using host plant quality as a diapause-inducing stimulus may be adaptive for herbivorous insects that use host plants whose phenology is unpredictable based on photoperiod or temperature. We examined the effects of leaf toughness of the woody vine Aristolochia kaempferi Willd. on larval performance and pupal diapause induction of the swallowtail butterfly Byasa alcinous Klug (Lepidoptera: Papilionidae). We also conducted field observations to assess whether human disturbance affects leaf phenology of A. kaempferi. Laboratory experiments showed that tough leaves decreased the survival rate of young larvae and lengthened the larval period, although pupal weight was not affected by leaf toughness. The incidence of pupal diapause was greater with tough leaves than with soft leaves and increased with larval duration. In the field, leaf age composition in A. kaempferi was greatly influenced by human mowing, which led to changes in leaf quality. These results suggest that B. alcinous has a plastic diapause strategy using host plant quality as a diapause-inducing stimulus, which may have evolved in frequently disturbed environments.

The Asian cockroach, Blattella asahinai Mizukubo (Dictyoptera: Blattellidae), was discovered in large numbers in southeastern Alabama in 2003. We surveyed southern Alabama and Georgia to determine the distribution of this species. In total, 67 of the 159 counties in Georgia and 33 counties of the 67 counties in Alabama were sampled. We found that B. asahinai was established in seven counties in Georgia and eight counties in Alabama. The area that B. asahinai has colonized in Alabama is double that of Georgia. The distribution of B. asahinai closely follows major highways and interstates, and it has likely expanded its range by using human transportation. Cold temperatures and suitable habitats are probably the only factors limiting the range of B. asahinai.

Lack of taxonomic and distributional information on the majority of taxonomic groups (i.e., invertebrates) in many cases leads to the greatest part of biodiversity being overlooked, and it may vitiate conservation efforts. We stress the need for, and feasibility of, overcoming this drawback in a case study analysis of total local diversity of Coleoptera in a Spanish relict forest (Natural Park of Fragas del Eume). We assessed the reliability of estimates derived from a generalist sampling inventory of the actual scores of richness and abundance of the various beetle families. We found that ≈1,000 species are estimated to live in such a small area (≈90 km²). Because efficiency of the generalist sampling protocol of beetle families was uneven, their inventory completeness varies with population size and heterogeneity of niche occupied. Comparison of the performance of several sampling-effort surrogates indicates that individuals seem to underestimate richness, compared with database records or sampling days, probably because conspecific individuals are spatially aggregated and thus the collection of several specimens does not imply a greater sampling effort than collecting only one specimen. The relationship between richness and abundance is dissimilar among families. Cerambycidae, found to have smaller populations than other families, but representing a large portion of beetle richness, should be considered a conservation priority in the prevention of biodiversity loss, because local extinction of small populations is more probable. Regional or broader scale patterns of beetle biodiversity cannot be addressed due to the lack of comparable inventories. Thus, fieldwork and taxonomic effort on hyperdiverse invertebrate groups should be encouraged and extensively funded to obtain reliable biodiversity information to enhance the effectiveness of conservation policies.

Scarab diversity in the Algodones Dunes (Imperial Co., CA) was assessed using a series of light-bucket transects to ascertain the impact of off-road vehicle (ORV) use. We compared dune endemic scarab species on the dunes south of Hwy. 78 that receive intense ORV use and the populations on the protected dunes north of Hwy. 78. We also compared the total numbers of Coleoptera collected. Our data indicate that unprotected dunes experienced a significant decline in Coleoptera populations, diversity, and species evenness. These results demonstrate that ORV use has a severe negative impact on Coleoptera that inhabit sand dunes.

We examined the consumption and oral toxicity of malathion bait to Anastrepha suspensa (Loew) (Diptera: Tephritidae) in a laboratory setting. Based on the malathion concentration in the bait and quantity of bait consumed, the malathion dose increased as bait malathion content increased. Mortality was about the same comparing 100 and 200,000 ppm malathion, but percentage of feeding was up to 7 times less for 200,000 ppm malathion. Approximately 10% of males and females survived in these tests, suggesting that the laboratory population of A. suspensa contains individuals resistant to malathion and malathion manufacture by-products. Solid phase microextraction collection and gas chromatography-mass spectrometry of volatile compounds suggest that malathion formulation contaminants were responsible for the mortality of flies that had no demonstrable contact with the malathion bait.

Conjugated linoleic acid (CLA) is an unusual fatty acid produced by fermentative bacteria in the rumen of ruminant mammals. Positive biological effects, including anticarcinogenic, antiatherogenic, and immune enhancing effects, have been observed in mammals fed CLA-enriched diets. Little is known of the biological effects of dietary CLA on insects, and nothing is known of the dietary CLA effects on the fatty acid profile of an insect. In this study, we examined the effects of a CLA or safflower oil-enriched meridic diet at several concentrations on European corn borer, Ostrinia nubilalis (Hübner), survival, development, fatty acid profiles, and fecundity. The fatty acid profiles of pupal and adult tissues as well as eggs from adults fed CLA-enriched diets as larvae were studied. Control insects were fed the meridic diet with the solvent carrier added. We hypothesized a CLA-enriched diet, but not a safflower oil-enriched diet, would decrease survival, alter fatty acid profiles, and decrease fecundity. Larvae fed the CLA-enriched diet developed more slowly than did larvae fed the safflower oil-enriched diet or the control diet. Pupal mass was not affected by any of the treatments. Survival was decreased greatly in larvae fed the CLA-enriched diet. Saturated fatty acids increased proportionately, whereas polyunsaturated and monounsaturated fatty acids decreased proportionately in both pupal and adult tissues. Fecundity was not affected by any of the treatments.

A thorough understanding of diapause development in insects is needed for prediction of population responses to climate change, for realistic simulation models, and for effective pest management. In Melanoplus sanguinipes F. and Melanoplus borealis (Fieber) (Orthoptera: Acrididae), diapause typically occurs in embryos at a late stage of development. Experiments were conducted to compare diapause traits in two populations of M. sanguinipes, one from Alaska and one from Idaho, and also in a population of M. borealis from Alaska. Respiration was measured at different stages of embryonic development. As the embryos entered diapause, respiration rates declined over a period of 4–8 d to levels ≈70% lower than peak rates of prediapause, late stage embryos, in all populations. In the Idaho population, subjecting prediapause embryos to a cold treatment (5°C) caused the embryo to avert diapause: respiration in these embryos continued to increase after chilling as the embryo developed directly to hatching. In M. borealis and M. sanguinipes from Alaska, chilling of prediapause embryos did not affect subsequent diapause development: respiration rates in these embryos increased until they entered diapause and then declined. About the same amount of time at 5°C was necessary to avert diapause in early stage embryos of the Idaho population as was required to terminate diapause in late stage embryos. Respiration rates of diapausing embryos increased with increasing time spent at 5°C. Respiration continued to increase after transfer to warm temperatures in those that had completed diapause, but in those that had not, respiration soon declined back to diapause levels. In general, there was less flexibility in the diapause program among grasshoppers from Alaska.

Larvae of Callosobruchus maculatus (F.) can coexist in a bean and exhibit scramble-type competition although the larvae can kill each other. Mechanisms to prevent or neutralize interference should be necessary for scramble-type competition. Previous studies reported that C. maculatus larvae can make walls to fill in their intersections after they encounter each other in a bean. To examine whether the wall-making is related to a mechanism behind scramble-type competition of C. maculatus, we examined larval wall-making behavior in a geographically isolated strain, in which the larvae exhibit scramble-type competition but retain interference ability. We conducted longitudinal dissection of beans with two hatched eggs to examine the pattern of wall-formation against larval development and the relationship between wall-making behavior and larval coexistence in a bean. The frequency of two individuals separated by the wall structure increased with developmental day, and eventually became higher than that of cases without encounter on the eighteenth day after oviposition. This indicates that the wall-making behavior may be associated with the coexistence of larvae in a bean. We also conducted an artificial interference experiment with pairs of larvae taken from beans with walls to examine whether larvae need to make walls for avoiding interference interaction. The pairs showed lethal fighting after the walls had been removed. This indicates that larvae made walls to avoid interfering with each other in a bean. These results support that wall-making behavior is a mechanism behind scramble-type competition in C. maculatus.

Results of previous field excavation of nest structure of Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), the Formosan subterranean termite, indicated that the total length of the gallery system ranged up to 580 m, and its total space may occupy >34,800 cm³. Because Formosan subterranean termite does not build mounds, it has been speculated that it creates tunnel space by compacting soil. The objective of this study is to test a “modified soil-compaction hypothesis” that Formosan subterranean termite removed and compacted soil to increase space during tunnel excavation. Contrary to the hypothesis, the deposited sand was less dense than the unexcavated sand in all replications; thus, we rejected the soil-compaction hypothesis. Instead, we offered wood-consumption hypothesis that termites gain the tunnel space as a result of consuming wood. When termites were placed with wood pieces for 30 d, the decreased volume of consumed wood was significantly higher than the increased volume of carton material. The net increased space is ≈50% of volume of consumed wood. We speculate that the space created by wood consumption could be transformed into tunnel space during soil displacement.