The unique epicuticular chemistry of Collembola - A cross-species analysis.

Springtails (Collembola), tiny hexapod arthropods, are abundant in the soil of most ecosystems, but our knowledge of their secondary metabolites is limited, in contrast to that of insects. In insects, the outer cuticle is usually covered by mixtures of long-chain hydrocarbons serving different functions, such as water regulation or chemical communication. In contrast, the knowledge of the epicuticular chemistry of springtails is scarce. We analyzed the cuticular lipids of 23 species covering different lineages. The often complicated structures were elucidated using gas chromatography/mass spectrometry, microderivatization, and synthesis. In contrast to insects, the terpene biosynthetic pathway is used for many of these lipids, producing unprecedented higher terpenes. In addition, evidence for de novo cholesterol biosynthesis in springtails was found, which is absent in insects. Finally, diverse non-insect linear compounds originating from the fatty acid biosynthetic pathway were identified. Our comparative analysis showed clear differences compared to insects and shed light on phylogenetic relationships.

Noxious stimulation induces self-protective behavior in bumblebees.

It has been widely stated that insects do not show self-protective behavior toward noxiously-stimulated body parts, but this claim has never been empirically tested. Here, we tested whether an insect species displays a type of self-protective behavior: self-grooming a noxiously-stimulated site. We touched bumblebees (Bombus terrestris) on an antenna with a noxiously heated (65°C) probe and found that, in the first 2 min after this stimulus, bees groomed their touched antenna more than their untouched antenna, and more than bees that were touched with an unheated probe or not touched at all did. Our results present evidence that bumblebees display self-protective behavior. We discuss the potential neural mechanisms of this behavior and the implications for whether insects feel pain.

Oviposition experience affects oviposition preference in Drosophila melanogaster.

Learning, memorizing, and recalling of potential ovipositing sites can influence oviposition preference. Classical conditioning experiments have shown that vinegar flies can learn the association of olfactory, gustatory, or visual stimuli with either positive or negative unconditioned stimuli. However, less is known about whether similar associations are formed in an ecologically more relevant context like during oviposition. Our experiments reveal that Drosophila melanogaster females increase their preference for substrates they have already experienced. However, this change of preference requires that the flies not only smelled or touched the substrates but also oviposited on them. We furthermore show that such an experience results in long-term memory lasting for at least 4 days, i.e., a duration that so far was shown only for aversive conditioning. Our study thus reveals a different form of associative learning in D. melanogaster that might be highly relevant for settling novel ecological niches.

First description of immature stages and notes on the biology of the blow fly, Calliphora lopesi Mello, 1962.

Several species of the worldwide distributed genus Calliphora Robineau-Desvoidy (Insecta, Diptera, Calliphoridae) are medically important vectors and agents of myiasis. Furthermore, these flies are relevant in forensics because they are found in corpses. Information regarding the taxonomy, bionomics and distribution of Calliphora species endemic to South America, including Calliphora lopesi Mello, is scarce. To expand knowledge on C. lopesi, this study presents descriptions of eggs, larvae, puparia and developmental data at 14, 17, 20, 23 and 26 ± 1°C for the first time. Adult flies were collected from the field and kept in the laboratory to obtain samples for morphological and biological studies. Immatures were examined using light and scanning electron microscopy. To assess the growth rate, 10 specimens from each temperature group were randomly removed from the diet and weighed every 24 h from larval hatching until pupation. The minimum developmental threshold, thermal constant and linear development-rate equations were calculated for each stage. Considering weight gain records and survival rates, the optimum temperature for the development of C. lopesi ranges from 23 to 26°C. A key to third-instar larvae of known Neotropical species of Calliphora was also provided to assist in identification. The information provided in this study should be useful in expanding knowledge about Neotropical Calliphoridae species of forensic importance.

Várias espécies do gênero Calliphora Robineau­Desvoidy (Insecta, Diptera, Calliphoridae), distribuídas mundialmente, são vetores e agentes causadoras de miíases clinicamente importantes. Além disso, tais moscas são relevantes no âmbito forense porque são encontradas em cadáveres. Informações sobre a taxonomia, bionomia e distribuição de espécies de Calliphora endêmicas da América do Sul, incluindo Calliphora lopesi Mello, ainda são escassas. Para ampliar o conhecimento sobre a espécie C. lopesi, este estudo apresenta pela primeira vez as descrições de ovos, larvas e pupários, assim como dados sobre o desenvolvimento de imaturos a 14, 17, 20, 23 e 26 ± 1°C. Moscas adultas foram coletadas no campo e mantidas em laboratório para obtenção de amostras para estudos morfológicos e biológicos. Os imaturos foram examinados utilizando microscopia óptica e eletrônica de varredura. Para avaliar a taxa de crescimento, 10 espécimes de cada grupo de temperatura foram retirados aleatoriamente do substrato em que se alimentavam e pesados a cada 24 horas, desde a eclosão das larvas até a pupariação. O limiar mínimo de desenvolvimento, a constante térmica e as equações lineares da taxa de desenvolvimento foram calculados para cada estágio. Levando em consideração os registros de ganho de peso e taxas de sobrevivência, a temperatura ótima para o desenvolvimento de C. lopesi varia de 23 a 26°C. Uma chave para larvas de terceiro estádio de espécies neotropicais conhecidas de Calliphora também está sendo disponibilizada para auxiliar na identificação. Espera­se que as informações fornecidas neste estudo possam ser úteis para ampliar o conhecimento sobre espécies Neotropicais de Calliphoridae de importância forense.

Decomposition of partially submerged remains: a study on the reliability of insect colonisation for PMI/PMSI estimation.

The terrestrial decomposition of remains and associated insect colonisation have been highly researched, and recently studies have expanded to investigate the aquatic decomposition of remains. However, there are instances where remains may experience both terrestrial and aquatic conditions simultaneously due to partial submersion in tidal areas, or influx or efflux of water caused by flood or drought. Decomposition and post-mortem interval (PMI) research to date has focused on remains wholly exposed to either terrestrial or aquatic environments, with limited consideration of dual simultaneous exposure. This study was conducted in artificial lentic environments to ascertain how simultaneous zones of terrestrial and aquatic environments on a single body may impact decomposition. Three trials were completed over a period of 12 months, with each trial consisting of 12 stillborn piglets; three partially submerged head exposed, three partially submerged abdomen exposed, three fully submerged aquatic controls and three terrestrial controls. Decomposition stage and rate were inferred from physical characteristics and insect activity. The decomposition rate of the exposed region of each piglet was significantly faster than the submerged region. The exposed zone of each was colonised by insects and reached skeletonization, whereas the submerged zone without orifice exposure had no insect activity and had a significantly slower decomposition rate. This indicated the ability to utilise terrestrial entomological approaches to estimate a minimum PMI for the exposed portion of the remains. However, without the ability to determine the amount of time the remains may have been submerged for, this estimation represents only a minimum PMSI, with the possibility the remains were submerged for a period of time without insect access and colonisation.

Forensic case reports of Dermestes maculatus (Coleoptera: Dermestidae) in Santa Catarina state, Southern Brazil.

Only a few cases describing the activity of dermestids on human corpses have been reported in the literature. Dermestes maculatus is a cosmopolitan beetle associated with carcasses at different decomposition stages, usually colonizing skeletonized and mummified remains. In this study, we presented two forensic case reports of D. maculatus associated with human corpses in Santa Catarina State, southern Brazil. In the first case, a human corpse in an advanced stage of decomposition was found hanged in an outdoor urban area. In the other one, a mummified cadaver was found inside of a closed house. In this last case, larvae of D. maculatus were essential to estimate the minimum postmortem interval (PMI) for the first time in Scientific Police of Santa Catarina. Our records highlight the significance of necrophagous beetles in ecological succession and in estimating PMI in cases involving human remains and corpses in advanced stage of decomposition.

GW4869 inhibitor affects vector competence and tick-borne flavivirus acquisition and transmission by blocking exosome secretion.

Exosomes/extracellular vesicles (EVs) are essential for the successful transmission of flaviviruses from vector to vertebrate host. Arthropod-EVs are envisioned as important target for blocking the transmission of vector-borne viral diseases. In this study, we show that the selective inhibition of EVs secretion by sphingomyelinase inhibitor, GW4869 significantly reduces vector efficiency and competence in acquiring and transmitting tick-borne flaviviruses. We show that GW4869 reduces EVs release from Langat Virus (LGTV)-infected Ixodes scapularis adult tick salivary glands (SGs). GW4869 treatment showed reduced dissemination of LGTV in SGs and other tissues within ticks. Decreased release of SG-EVs directly correlated with reduced tick blood-feeding efficiency, engorgement weights, and reduction in LGTV acquisition/transmission. Our data indicates that LGTV infection significantly improves molting/fitness, and survival efficiency of ticks and GW4869 alone affects the repletion rates of blood-feeding naïve-ticks. Overall, we provide evidence for GW4869 potential use as therapeutic agent in the tick control and prevention of tick-borne flaviviral transmission.

Comparative genomic analyses on assassin bug Rhynocoris fuscipes (Hemiptera: Reduviidae) reveal genetic bases governing the diet-shift.

Genetic basis underlying the biodiversity and phenotypic plasticity are fascinating questions in evolutionary biology. Such molecular diversity can be achieved at multi-omics levels. Here, we sequenced the first chromosome-level genome of assassin bug Rhynocoris fuscipes, a polyphagous generalist predator for biological control of agroecosystems. Compared to non-predatory true bugs Apolygus lucorum and Riptortus pedestris, the R. fuscipes-specific genes were enriched in diet-related genes (e.g., serine proteinase, cytochrome P450) which had higher expression level and more exons than non-diet genes. Extensive A-to-I RNA editing was identified in all three species and showed enrichment in genes associated with diet in R. fuscipes, diversifying the transcriptome. An extended analysis between five predaceous and 27 phytophagous hemipteran species revealed an expansion of diet-related genes in R. fuscipes. Our findings bridge the gap between genotype and phenotype, and also advance our understanding on genetic and epigenetic bases governing the diet shifts in ture bugs.

A methodological approach to age estimation of the intra-puparial period of the forensically relevant blow fly Calliphora vicina via Fourier transform infrared spectroscopy.

Estimating the age of immature blow flies is of great importance for forensic entomology. However, no gold-standard technique for an accurate determination of the intra-puparial age has yet been established. Fourier transform infrared (FTIR) spectroscopy is a method to (bio-)chemically characterise material based on the absorbance of electromagnetic energy by functional groups of molecules. In recent years, it also has become a powerful tool in forensic and life sciences, as it is a fast and cost-effective way to characterise all kinds of material and biological traces. This study is the first to collect developmental reference data on the changes in absorption spectra during the intra-puparial period of the forensically important blow fly Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae). Calliphora vicina was reared at constant 20°C and 25°C and specimens were killed every other day throughout their intra-puparial development. In order to investigate which part yields the highest detectable differences in absorption spectra throughout the intra-puparial development, each specimen was divided into two different subsamples: the pupal body and the former cuticle of the third instar, that is, the puparium. Absorption spectra were collected with a FTIR spectrometer coupled to an attenuated total reflection (ATR) unit. Classification accuracies of different wavenumber regions with two machine learning models, i.e., random forests (RF) and support vector machines (SVMs), were tested. The best age predictions for both temperature settings and machine learning models were obtained by using the full spectral range from 3700 to 600 cm-1. While SVMs resulted in better accuracies for C. vicina reared at 20°C, RFs performed almost as good as SVMs for data obtained from 25°C. In terms of sample type, the pupal body gave smoother spectra and usually better classification accuracies than the puparia. This study shows that FTIR spectroscopy is a promising technique in forensic entomology to support the estimation of the minimum post-mortem interval (PMImin), by estimating the age of a given insect specimen.

New directions for malaria vector control using geography and geospatial analysis.

As we strive towards the ambitious goal of malaria elimination, we must embrace integrated strategies and interventions. Like many diseases, malaria is heterogeneously distributed. This inherent spatial component means that geography and geospatial data is likely to have an important role in malaria control strategies. For instance, focussing interventions in areas where malaria risk is highest is likely to provide more cost-effective malaria control programmes. Equally, many malaria vector control strategies, particularly interventions like larval source management, would benefit from accurate maps of malaria vector habitats - sources of water that are used for malarial mosquito oviposition and larval development. In many landscapes, particularly in rural areas, the formation and persistence of these habitats is controlled by geographical factors, notably those related to hydrology. This is especially true for malaria vector species like Anopheles funestsus that show a preference for more permanent, often naturally occurring water sources like small rivers and spring-fed ponds. Previous work has embraced geographical concepts, techniques, and geospatial data for studying malaria risk and vector habitats. But there is much to be learnt if we are to fully exploit what the broader geographical discipline can offer in terms of operational malaria control, particularly in the face of a changing climate. This chapter outlines potential new directions related to several geographical concepts, data sources and analytical approaches, including terrain analysis, satellite imagery, drone technology and field-based observations. These directions are discussed within the context of designing new protocols and procedures that could be readily deployed within malaria control programmes, particularly those within sub-Saharan Africa, with a particular focus on experiences in the Kilombero Valley and the Zanzibar Archipelago, United Republic of Tanzania.

Variations in cuticular hydrocarbons of Calliphora vicina (Diptera: Calliphoridae) empty puparia: Insights for estimating late postmortem intervals.

Necrophagous flies, particularly blowflies, serve as vital indicators in forensic entomology and ecological studies, contributing to minimum postmortem interval estimations and environmental monitoring. The study investigates variations in the predominant cuticular hydrocarbons (CHCs) viz. n-C25, n-C27, n-C28, and n-C29 of empty puparia of Calliphora vicina Robineau-Desvoidy, 1830, (Diptera: Calliphoridae) across diverse environmental conditions, including burial, above-ground and indoor settings, over 90 days. Notable trends include a significant decrease in n-C25 concentrations in buried and above-ground conditions over time, while n-C27 concentrations decline in buried and above-ground conditions but remain stable indoors. Burial conditions show significant declines in n-C27 and n-C29 concentrations over time, indicating environmental influences. Conversely, above-ground conditions exhibit uniform declines in all hydrocarbons. Indoor conditions remain relatively stable, with weak correlations between weathering time and CHC concentrations. Additionally, machine learning techniques, specifically Extreme Gradient Boosting (XGBoost), are employed for age estimation of empty puparia, yielding accurate predictions across different outdoor and indoor conditions. These findings highlight the subtle responses of CHC profiles to environmental stimuli, underscoring the importance of considering environmental factors in forensic entomology and ecological research. The study advances the understanding of insect remnant degradation processes and their forensic implications. Furthermore, integrating machine learning with entomological expertise offers standardized methodologies for age determination, enhancing the reliability of entomological evidence in legal contexts and paving the way for future research and development.

Mapping environmental suitability changes for arbovirus mosquitoes in Southeast Asia: 1960-2020.

Spatial epidemiology recognizes the impact of environmental factors on human infectious diseases through disease vectors. The expansion of Aedes aegypti and Aedes albopictus raises concerns about health risks due to their changing distribution. However, current mosquito mapping methods have low spatial resolution and limited focus on long-term trends and factors. This study develops a high-resolution framework (500 m) to map mosquito distribution in Southeast Asia from 1960 to 2020. It includes a species distribution model, a spatial autocorrelation model, and a geographical detector model. The study produces Southeast Asia's first 500 m resolution map of mosquito suitability, revealing significant increases in mosquito suitability in most cities over the past 60 years. The analysis indicates a shift in high-suitability areas from coastal to inland regions, with nighttime land surface temperature playing a key role. These findings are crucial for regional risk assessments and mitigation strategies related to vector-borne diseases.

Validation of heat-inducible Ixodes scapularis HSP70 and tick-specific 3xP3 promoters in ISE6 cells.

Ixodes scapularis is an important vector of many pathogens, including the causative agent of Lyme disease. The gene function studies in I. scapularis and other ticks are hampered by the lack of genetic tools, including an inducible promoter for temporal control over transgene-encoding protein or double-stranded RNA. We characterized an intergenic sequence upstream of a heat shock protein 70 (HSP70) gene that can drive Renilla luciferase and mCherry expression in the I. scapularis cell line ISE6 (IsHSP70). In another construct, we replaced the Drosophila melanogaster minimal HSP70 promoter of the 3xP3 promoter with a minimal portion of IsHSP70 promoter and generated an I. scapularis-specific 3xP3 (Is3xP3) promoter. Both IsHSP70 and Is3xP3 have a heat-inducible expression of mCherry fluorescence in ISE6 cells with an approximately 10-fold increase in the percentage of fluorescent cells upon 2 h heat shock. These promoters described will be valuable tools for gene function studies.

Survival of Calliphora vicina (Diptera: Calliphoridae) embryos under cold temperature conditions: forensic implications.

Most blow flies (Diptera: Calliphoridae) species are sarcosaprophagous during the larval stage, primarily feeding on the soft tissues of carcasses during the early stages of decomposition, making them valuable forensic indicators for minimum post-mortem interval (minPMI) estimations. Like other insects, their developmental rates are strongly influenced by the environmental temperature. Although several studies have examined the influence of temperature on the development of different blow fly species, the impact of cold temperatures remains largely unstudied, despite its potential forensic implications. The present study investigates the effect of three cold temperatures (0, -2.5 and -5°C) on the survival of Calliphora vicina embryos of five different ages (0%, 20%, 40%, 60% and 80% of the total embryonic development) and two exposure times (6 and 24 h). Our results revealed significant differences in egg survival at the earliest embryonic stages (0% and 20% of the total embryonic development), resulting in high mortality rates. While at 20% of the total embryonic development high mortality was only observed under -5°C, at 0% of the total embryonic development high mortality rates were observed at all the temperatures tested. Although C. vicina embryos demonstrate tolerance to cold temperatures once they have completed the first 20% of the total embryonic development, potentially mitigating the impact of cold weather events, the possibility of minPMI underestimations due to the death of the first egg batches should not be disregarded. Additionally, considering that the embryonic development stages may last for several days under low temperatures, caution should be taken in the analysis of entomological evidence if a cadaver is discovered following cold weather episodes.

Sampling of Culicoides with nontraditional methods provides unusual species composition and new records for southern Spain.

BACKGROUND: Culicoides midges have been well-studied in Spain, particularly over the last 20 years, mainly because of their role as vectors of arboviral diseases that affect livestock. Most studies on Culicoides are conducted using suction light traps in farmed environments, but studies employing alternative trapping techniques or focusing on natural habitats are scarce. METHODS: In the present study, we analyze Culicoides captured in 2023 at 476 sites in western Andalusia (southern Spain) using carbon dioxide-baited Biogents (BG)-sentinel traps across different ecosystems. RESULTS: We collected 3,084 Culicoides midges (3060 females and 24 males) belonging to 23 species, including the new species Culicoides grandifovea sp. nov. and the first record of Culicoides pseudolangeroni for Europe. Both species were described with morphological and molecular methods and detailed data on spatial distribution was also recorded. The new species showed close phylogenetic relations with sequences from an unidentified Culicoides from Morocco (92.6% similarity) and with Culicoides kurensis. Culicoides imicola was the most abundant species (17.4%), followed by Culicoides grandifovea sp. nov. (14.6%) and Culicoides kurensis (11.9%). Interestingly, Culicoides montanus was the only species of the obsoletus and pulicaris species complexes captured, representing the first record of this species in southern Spain. A total of 53 valid Culicoides species have been reported in the area, with 48 already reported in literature records and 5 more added in the present study. Information on the flight period for the most common Culicoides species is also provided. CONCLUSIONS: To the best of our knowledge, our study represents the most comprehensive effort ever done on nonfarmland habitats using carbon-dioxide baited suction traps for collecting Culicoides. Our data suggests that using carbon dioxide traps offers a completely different perspective on Culicoides communities compared with routinely used light traps, including the discovery of previously unrecorded species.

Invasive Anopheles stephensi in Africa: insights from Asia.

Anopheles stephensi is a highly competent urban malaria vector species, endemic in South Asia and the Persian Gulf, which has colonised eight countries in sub-Saharan Africa (SSA) since 2013 and is now spreading uncontrollably. In urban areas of Africa, where malaria transmission has previously been low or non-existent, the invasion of An. stephensi represents a significant problem, particularly to immunologically naïve populations. Despite this rapidly advancing threat, there is a paucity of information regarding the bionomics of An. stephensi in SSA. Here, we offer a critical synthesis of literature from An. stephensi's native range, focusing on the future of An. stephensi in a rapidly urbanising Africa, and highlighting key questions that warrant prioritisation by the global malaria vector control community.

Lucilia cuprina (Wiedemann) (Diptera: Calliphoridae): A potentially forgotten forensically important species in Malaysia.

Lucilia cuprina (Wiedemann) (Diptera: Calliphoridae) has been collected in human forensic case work. This species is endemic in Malaysia but is not one of the most common species and is often found in outdoor cases. However, it is hypothesized that the presence of L. cuprina larvae may provide useful information in forensic case studies in Malaysia where this species has previously been ignored. This review will discuss the current background knowledge on L. cuprina, particularly when it comes to other forensic cases in Malaysia. General biology as well as key information for forensic work such as geographical distribution and developmental data will be reviewed. Finally, we discuss the potential for L. cuprina to provide beneficial and unique forensic insight into indoor cases with refuse.

Differences in male Aedes aegypti and Aedes albopictus hearing systems facilitate recognition of conspecific female flight tones.

When Aedes albopictus mosquitoes invade regions predominated by Aedes aegypti, either the latter can be displaced or the species can coexist, with potential consequences on disease transmission. Males from both species identify females by listening for her flight sounds. Comparing male hearing systems may provide insight into how hearing could prevent interspecific mating. Here, we show that species-specific differences in female wing beat frequencies are reflected in differences in male ear mechanical tuning frequencies and sound response profiles. Though Aedes albopictus males are attracted to sound, they do not readily display abdominal bending, unlike Aedes aegypti. We observed interspecific differences in male ear mechanical, but not electrical, tuning, suggesting a conserved primary auditory processing pathway. Our work suggests a potential role for hearing in the premating isolation of Aedes aegypti and Aedes albopictus, with implications for predicting future dynamics in their sympatric relationships and our understanding of mosquito acoustic communication.

Intrapuparial stage aging and PMI estimation based on the developmental transcriptomes of forensically important Aldrichina grahami (Diptera: Calliphoridae) gene expression.

Background: The expression profiles of differentially expressed genes (DEGs) during pupal development have been demonstrated to be vital in age estimation of forensic entomological study. Here, using forensically important Aldrichina grahami (Diptera: Calliphoridae), we aimed to explore the potential of intrapuparial stage aging and postmortem interval (PMI) estimation based on characterization of successive developmental transcriptomes and gene expression patterns. Methods: We collected A. grahami pupae at 11 successive intrapuparial stages at 20 °C and used the RNA-seq technique to build the transcriptome profiles of their intrapuparial stages. The DEGs were identified during the different intrapuparial stages using comparative transcriptome analysis. The selected marker DEGs were classified and clustered for intrapuparial stage aging and PMI estimation and then further verified for transcriptome data validation. Ultimately, we categorized the overall gene expression levels as the dependent variable and the age of intrapuparial A. grahami as the independent variable to conduct nonlinear regression analysis. Results: We redefined the intrapuparial stages of A. grahami into five key successive substages (I, II, III, IV, and V), based on the overall gene expression patterns during pupal development. We screened 99 specific time-dependent expressed genes (stage-specific DEGs) to determine the different intrapuparial stages based on comparison of the gene expression levels during the 11 developmental intrapuparial stages of A. grahami. We observed that 55 DEGs showed persistent upregulation during the development of intrapuparial A. grahami. We then selected four DEGs (act79b, act88f, up and ninac) which presented consistent upregulation using RT-qPCR (quantitative real-time PCR) analysis, along with consideration of the maximum fold changes during the pupal development. We conducted nonlinear regression analysis to simulate the calculations of the relationships between the expression levels of the four selected DEGs and the developmental time of intrapuparial A. grahami and constructed fitting curves. The curves demonstrated that act79b and ninac showed continuous relatively increasing levels. Conclusions: This study redefined the intrapuparial stages of A. grahami based on expression profiles of developmental transcriptomes for the first time. The stage-specific DEGs and those with consistent tendencies of expression were found to have potential in age estimation of intrapuparial A. grahami and could be supplementary to a more accurate prediction of PMI.

Novel use of a servosphere to study apodous insects: Investigation of blow fly post-feeding larval dispersal.

Blow flies (Diptera: Calliphoridae) are arguably the most important providers of an estimate of minimum post-mortem interval in forensic investigations. They usually undergo a post-feeding dispersal from the body. While previous studies have looked at dispersal of groups of larvae, recording the dispersal activity of individual larvae has not previously been demonstrated. A servosphere was used here to record the speed, directionality and phototaxis of individual post-feeding larvae of two species of blow fly on a smooth plastic surface over time. The servosphere rotates to compensate for the movement of an insect placed at its apex, thereby enabling its unimpeded locomotion in any direction to be studied and behavioural changes to external stimuli recorded. To our knowledge, the servosphere has not previously been used to study apodous insects. The objective of our study was to compare dispersal behaviour of Calliphora vicina Robineau-Desvoidy and Protophormia terraenovae (Robineau-Desvoidy), both common primary colonisers of human and animal cadavers, but showing different post-feeding dispersal strategies. Larvae of C. vicina generally disperse from the body while those of P. terraenovae remain on or close to the body. Our aims were to study (1) changes in dispersal speed over a 1-h period; (2) changes in dispersal speed once a day for 4 days, between the end of feeding and onset of pupariation; and (3) response of dispersing larvae to light. We demonstrated that (1) the movement of three C. vicina larvae tracked for 1 continuous hour on 1 day slowed from an average of 3 to <1.7 mms-1; (2) the average speed of 20 larvae of C. vicina (4.08 mms-1) recorded for 5 min once per day over a 4-day period between onset of dispersal and pupariation was significantly greater than that of P. terraenovae (2.36 mms-1; p < 0.0001), but that speed of both species increased slightly over the 4 days; (3) the responses of larvae of C. vicina to changes in light direction from the four cardinal directions of the compass, showed that they exhibited a strong negative phototactic response within 5 s, turning to move at approximately 180° away from the new light position. While conducted to observe larval calliphorid post-feeding behaviour, the results of this proof of concept study show that apodous insects can be studied on a servosphere to produce both qualitative and quantitative data.