Publications by authors named "Thomas Chouvenc"

The Formosan subterranean termite, Coptotermes formosanus Shiraki, is both an economically impactful pest and a successful invader. One method of subterranean termite control is baiting. According to the label, baits are installed surrounding the structure at a uniform interval distance of ≈3 m.

View Article and Find Full Text PDF

In 1995, the launch of the first commercial chitin synthesis inhibitor (CSI) bait led to the transformation of the subterranean termite control industry around the world. Their slow mode of action, which relies on both their ability to be transferred among nestmates and termite molting biology, has made them cost-effective solutions for subterranean termite colony elimination while minimizing the introduction of pesticides into the soil toward an environmentally sustainable strategy. However, despite successful commercial implementations, the acceptance of their use varies within the pest control industry around the world.

View Article and Find Full Text PDF
Article Synopsis
  • - The classification of termites, particularly the diverse Neoisoptera group, needs significant updates due to many incorrectly grouped taxa; researchers propose a new classification based on genomic analyses.
  • - The study identifies seven monophyletic family lineages within Neoisoptera and 18 subfamily lineages in the species-rich Termitidae, including several new subfamilies and the revival of some older ones.
  • - The new classification method is built on clear monophyletic lineages, which enhances its stability and adaptability for future studies, allowing it to incorporate yet-to-be-discovered species easily.
View Article and Find Full Text PDF

The use of nonrepellent liquid termiticides against subterranean termites has long relied on the assumption that foraging termites in soils could transfer toxicants to nestmates to achieve population control. However, their dose-dependent lethal time can lead to rapid termite mortality in proximity of the treatment, triggering secondary repellency. The current study characterizes the dynamic nature of the "death zone," i.

View Article and Find Full Text PDF

Hybridization between invasive pest species may lead to significant genetic and economic impacts that require close monitoring. The two most invasive and destructive termite species worldwide, Coptotermes formosanus Shiraki and Coptotermes gestroi (Wasmann), have the potential for hybridization in the field. A three-year field survey conducted during the dispersal flight season of Coptotermes in Taiwan identified alates with atypical morphology, which were confirmed as hybrids of the two Coptotermes species using microsatellite and mitochondrial analyses.

View Article and Find Full Text PDF

With recent evidence of hybridization events in the field, the phenotypic traits of F1 hybrid colonies of 2 destructive subterranean termite species, Coptotermes formosanus Shiraki and Coptotermes gestroi (Wasmann) remain to be investigated. In this study, laboratory colonies of 2 conspecific pairings and 2 heterospecific pairings (hybrid F = ♀C. formosanus × ♂C.

View Article and Find Full Text PDF

Background: To control subterranean termite pests, chitin synthesis inhibitor (CSI) baits have been widely applied. Despite CSI baits having low impacts on the environment, they require a lengthy time period to eliminate colonies. 20-hydroxyecdysone (20E) was proposed to speed up the baiting process as it showed faster mortality than CSI baits.

View Article and Find Full Text PDF

The traditional stake survey and in-ground (IG) monitoring stations have been ineffective in aggregating the Asian subterranean termite, Coptotermes gestroi (Wasmann) in southeastern Florida. In this study, we used both IG and above-ground (AG) Sentricon stations to monitor and bait C. gestroi, and as expected, none of the 83 IG stations was intercepted.

View Article and Find Full Text PDF

Perfume making in male orchid bees is a unique behavior that has given rise to an entire pollination syndrome in the neotropics. Male orchid bees concoct and store species-specific perfume mixtures in specialized hind-leg pockets using volatiles acquired from multiple environmental sources, including orchid flowers. However, the function and the ultimate causes of this behavior have remained elusive.

View Article and Find Full Text PDF

Nitrogen, a limiting growth factor in wood-feeding insects, was hypothesized to play a role in the recently discovered behavior of subterranean termites returning to the nest to molt. Coptotermes gestroi (Wasmann) exuviae is approximately 11% N by dry weight, and therefore a potentially rich source of recyclable nitrogen. Exuviae from a C.

View Article and Find Full Text PDF
Article Synopsis
  • Wood-feeding termites have developed strategies to conserve nitrogen due to their nitrogen-poor diet and produce nitrogen-rich exuviae during molting, which can be recycled within the colony.
  • In the study of Coptotermes gestroi, adding exuviae to nitrogen-poor colonies resulted in significant biomass gains, highlighting the importance of these resources for growth.
  • Conversely, the absence of exuviae negatively impacted egg-laying by queens, showing that the recycling of these nitrogen sources supports reproductive success and colony development in environments with limited nitrogen availability.
View Article and Find Full Text PDF

Coptotermes formosanus Shiraki and C. gestroi (Wasmann) are economically important structural pests in urban areas. Due to anthropogenic activity, both species have been introduced into the United States, with their respective invasive ranges now overlapping in Florida, and the two species have the capability to hybridize.

View Article and Find Full Text PDF

Termites (Blattodea: Isoptera) have evolved specialized defensive strategies for colony protection. Alarm communication enables workers to escape threats while soldiers are recruited to the source of disturbance. Here, we study the vibroacoustic and chemical alarm communication in the wood roach Cryptocercus and in 20 termite species including seven of the nine termite families, all life-types, and all feeding and nesting habits.

View Article and Find Full Text PDF

Elaborate task allocation is key to the ecological success of eusocial insects. Termite colonies are known for exhibiting age polyethism, with older instars more likely to depart the reproductive center to access food. However, it remains unknown how termites retain this spatial structure against external disturbances.

View Article and Find Full Text PDF

Background: Foraging in group living animals such as social insects, is collectively performed by individuals. However, our understanding on foraging behavior of subterranean termites is extremely limited, as the process of foraging in the field is mostly concealed. Because of this limitation, foraging behaviors of subterranean termites were indirectly investigated in the laboratory through tunnel geometry analysis and observations on tunneling behaviors.

View Article and Find Full Text PDF

Intrinsic dinitrogen (N) fixation by diazotrophic bacteria in termite hindguts has been considered an important pathway for nitrogen acquisition in termites. However, studies that supported this claim focused on measuring instant N fixation rates and failed to address their relationship with termite colony growth and reproduction over time. We here argue that not all wood-feeding termites rely on symbiotic diazotrophic bacteria for colony growth.

View Article and Find Full Text PDF

Subterranean termite control methods using chitin synthesis inhibitors (CSIs) aim at eliminating colonies that feed upon a bait formulation. Several benzoylurea active ingredient formulations are currently commercially available as alternative termite management strategies to liquid termiticides. Individual workers need to molt on a regular basis and CSIs interfere with such molting process, allowing sufficient time for the acquisition of a colony-wide lethal dose prior to widespread mortality.

View Article and Find Full Text PDF

AbstractCuticular hydrocarbons (CHCs) are waxy compounds on the surface of insects that prevent desiccation and frequently serve as chemical signals mediating social and mating behaviors. Although their function in eusocial species has been heavily investigated, little is known about the evolution of CHC-based communication in species with simpler forms of social organization lacking specialized castes. Here we investigate factors shaping CHC variation in the orchid bee , which forms casteless social groups of two to three individuals.

View Article and Find Full Text PDF

In collective animal motion, coordination is often achieved by feedback between leaders and followers. For stable coordination, a leader's signals and a follower's responses are hypothesized to be attuned to each other. However, their roles are difficult to disentangle in species with highly coordinated movements, hiding potential diversity of behavioural mechanisms for collective behaviour.

View Article and Find Full Text PDF

Subterranean termites are hemimetabolous social insects where most of the individuals in a colony molt on a regular basis until they die. Nitrogen is a limiting growth factor in wood-feeding insects, such as termites. Because the exuviae of molting termites are consumed by nestmates, it is possible that exuviae represent a potential source of nitrogen that could be recycled and be part of the overall nitrogen conservation strategy of the colony.

View Article and Find Full Text PDF

The development of baits for subterranean termite control over the past 25 yr has provided cost-effective alternatives to liquid termiticide treatments. Current bait products use one of the few available benzoylurea chitin synthesis inhibitors (CSIs) labeled for subterranean termites. These insecticides are used because of their nonrepellency, their slow-acting mode of action, and their dose-independent lethal time.

View Article and Find Full Text PDF
Article Synopsis
  • - The Formosan subterranean termite, Coptotermes formosanus, is a major invasive pest originally from eastern Asia, now found in places like Hawaii and the southeastern US.
  • - Through a study using around 22,000 SNPs, researchers mapped the termite's invasion history and discovered multiple introduction events from eastern Asia, showing a complex pattern of invasion.
  • - One introduction to Hawaii provided genetic material that later contributed to populations in the southeastern US, while another introduction from southcentral China resulted in additional genetic diversity, highlighting the importance of multiple introductions for the species' survival and distribution.
View Article and Find Full Text PDF

Termites are a clade of eusocial wood-feeding roaches with > 3000 described species. Eusociality emerged ~ 150 million years ago in the ancestor of modern termites, which, since then, have acquired and sometimes lost a series of adaptive traits defining of their evolution. Termites primarily feed on wood, and digest cellulose in association with their obligatory nutritional mutualistic gut microbes.

View Article and Find Full Text PDF

Cuticular hydrocarbons (CHCs) have, in insects, important physiological and ecological functions, such as protection against desiccation and as semiochemicals in social taxa, including termites. CHCs are, in termites, known to vary qualitatively and/or quantitatively among species, populations, castes, or seasons. Changes to hydrocarbon profile composition have been linked to varying degrees of aggression between termite colonies, although the variability of results among studies suggests that additional factors might have been involved.

View Article and Find Full Text PDF

Search theory predicts that animals evolve efficient movement patterns to enhance encounter rates with specific targets. The optimal movements vary with the surrounding environments, which may explain the observation that animals often switch their movement patterns depending on conditions. However, the effectiveness of behavioural change during search is rarely evaluated because it is difficult to examine the actual encounter dynamics.

View Article and Find Full Text PDF