Forensic implication of cadaveric behaviors of the Japanese pavement ant (Tetramorium tsushimae Emery) attending to rabbit cadavers

It is noticed by some researchers that ants may cause some forensic confusion in understanding death scenes. In the aspect of relationship between the ant‐animal decomposition, we observed the behavior of ants congregating on dead animals. Amongst various species of ants visiting dead rabbits, Tetramorium tsushimae Emery was noticeable in producing scratched scars, mounds, and nests around dead rabbits and covering them with soils. The behaviors are likely to interfere or to disturb the usual process of decomposition succession lead by maggots. We discussed that a series of cadaveric behaviors of T. tsushimae may be used as a potential forensic hint not to misunderstand death scenes disturbed by the species.     

Territorial ants delay carrion decomposition by depressing Diptera larvae in a Tibetan alpine meadow

1. Invertebrates contribute largely to the decomposition of animal carcasses in natural ecosystems. However, we currently lack experimental evidence for the impact of predatory ants on carrion decomposition. Provided that many ant species display their role in the necrophilous community as predators but not as decomposers, we hypothesized that the ants would negatively affect the carrion decomposition rates by predating on other insect decomposers. 2. In a Tibetan alpine meadow, we conducted a one-factor designed field experiment involving three treatments, that is, 20, 60, and 500 cm of yak (Bos grunniens) carrion plots away from anthills (Camponotus herculeanus), which mirrored the high, intermediate, and low ant abundance, respectively. 3. Our results show that the necrophilous community assemblage differed significantly along the distance gradients from anthills, with the dominance of the necrophilous community shifting from ants in the 20 cm treatment to maggots in the 500 cm treatment. The ants significantly decreased the number of maggots through predation, resulting in a significant decrease of the carrion decomposition rates. However, ants did not change the number of other scavengers albeit they attacked them. 4. These results suggest that the predatory ant C. herculeanus can modify the carrion decomposition rates through generating a strong consumptive effect on decomposers, which is important to understand the necrophilous community assemblage and the decomposition of animal-based materials.     

Oral myiasis in an elderly patient

doi: 10.1111/j.1741‐2358.2010.00432.x Oral myiasis in an elderly patient Background: Myiasis is the invasion of living tissue of humans and other mammals by eggs or maggots of flies of the order of Diptera. It occurs mainly in the Tropics and is associated with inadequate public and personal hygiene. Oral myiases in an older man appears to be rare. Objective: To relate a case of oral myiases in a debilitated older man treated by mechanical removal of the maggots, identifying the adult insect that caused the infestation. Methods: The diagnosis of oral myiasis was established by the clinical examination and it was detected that the infestation involved only soft tissue and the sinus cavity. The patient was submitted to two mechanical removal of the visible maggots. Results: Total of 110 maggots was removed from the oral cavity of the patient and adult insects was identified as belonging to the Calliphoridae Family, Cochliomyia hominivorax species. The patient died two days after the second procedure by severe systemic complications. Conclusions: The mechanic removal and the identification of the maggots must be adopted as soon as possible to prevent further tissue damage and bacterial infection in cases of oral myiasis. Special attention should be given to the debilitated old patients that are particularly susceptible to oral myiasis infestation.     

Effects of Argentine ants (Hymenoptera: Formicidae) on myrmecophilous lycaenid butterfly,Narathura bazalus (Lepidoptera: Lycaenidae), in western Japan

Effects of the invasive Argentine ant, Linepithema humile (Mayr), on a myrmecophilous butterfly, Narathura bazalus (Hewiston), were investigated in the field in western Japan. Larvae of N. bazalus were attended by workers of Argentine ants in invaded parks and of ten native and one cosmopolitan ant species in uninvaded parks. The abundance of eggs and larvae were not significantly different between invaded and uninvaded parks. Pupal weight and parasitized ratio by tachinid flies were also not different between the two types of parks. These results indicate that the role of Argentine ants for the butterfly might be almost equivalent to the native ants.     

The significance of opportunistic predators for the sympatric carnivorous plant species Drosera intermedia and Drosera rotundifolia

Summary Earlier feeding experiments with Drosera in the field using adult Drosophila melanogaster as prey had shown that D. intermedia reacts three times as strong with respect to biomass production as the sympatric species D. rotundifolia. The present study shows that in D. rotundifolia only 29% of added flies remain on the leaves for more than 24 h, but 95% in D. intermedia. Opportunistic predators, mostly ants, are likely to be responsible for this difference. Ants were often observed robbing food from the leaves of D. rotundifolia, and showed a much higher activity in the microhabitat of this species. In both species of Drosera larger individuals were better than smaller ones in retaining added flies. The activity of ants significantly increased with air temperature and the duration of sunshine. The advantage of plundering seems to be more important for the ants than the danger of being caught. The prey collected from Drosera may be an important source of food for bog-dwelling ants.     

Social wasps (Vespidae: Polistinae) on carcasses of Rattus norvegicus (Mammalia: Muridae) in the Central Amazonia,Brazil: possible forensic implications

We evaluated the occurrence of social wasps in the decomposition process in tropical rainforest in central Amazonia (Ducke Reserve, Manaus, Brazil), using cadavers of rats as attractants, exposed in suspended cages. Ten species, in three genera, of social wasps were collected only in the initial stages of decay (fresh and bloated). Five species were collected, mainly in the fresh stage, feeding on flesh: Agelaia angulata, Agelaia constructor, Agelaia fulvofasciata, Agelaia pallipes and Angiopolybia pallens. Five species were collected, mainly in the bloated stage, feeding on flesh and eggs and first instar larvae of dipteran: Agelaia testacea, Angiopolybia obidensis, Apoica arborea, Apoica pallens and Apoica thoracica. Due to the aspect of the injuries caused by the wasps to the carcass, they may be mistaken as skin ulcers, burns or abrasions, which may mislead a forensic investigation.     

Diversity of bacteria in different life stages and their impact on the development and reproduction of Zeugodacus tau (Diptera: Tephritidae)

Fruit flies usually harbor diverse communities of bacteria in their digestive systems,which are known to play a significant role in their fitness.However,little information is available on Zeugodacus tau,a polyphagous pest worldwide.This study reports the first extensive analysis of bacterial communities in different life stages and their effect on the development and reproduction of laboratory-reared Z tan.Cultured bacteria were identified using the conventional method and all bacteria were identified by highthroughput technologies(16S ribosomal RNA gene sequencing of V3-V4 region).A total of six bacterial phyla were identified in larvae,pupae,and male and female adult flies,which were distributed into 14 classes,32 orders,58 families and 96 genera.Proteobacteria was the most represented phylum in all the stages except larvae.Enterobacter,Klebsiella,Providencia,and Pseudomonas were identified by conventional and next-generation sequencing analysis in both male and female adult flies,and Enterobacter was found to be the main genus.After being fed with antibiotics from the first instar larvae,bacterial diversity changed markedly in the adult stage.Untreated flies laid eggs and needed 20 days before oviposition while the treated flies showed ovary development inhibited and were not able to lay eggs,probably due to the alteration of the microbiota.These findings provide the cornerstone for unexplored research on bacterial function in Z tau,which will help to develop an environmentally friendly management technique for this kind of harmful insect.     

Fungal microbiota dynamics as a postmortem investigation tool: focus on Aspergillus,Penicillium and Candida species

Aims: To investigate the presence of fungi during three human decomposition stages: bloated, putrefaction and skeletonization. Methods and Results: The samples were gathered in the city of Fortaleza, Ceará, Brazil, from the public morgue and cemeteries. The material was submitted to conventional mycological procedures by direct examination and macro/micro morphological and biochemical analyses. The main fungi isolated were Aspergillus spp., Penicillium spp. and Candida spp. in the bloated stage (n = 34 cadavers) and in the putrefaction stage (n = 6 cadavers), while in the skeletonization stage (n = 20 cadavers), the main fungi were Aspergillus spp., Penicillium spp. and Mucor sp. Conclusions: Aspergillus, Penicillium and Candida species were associated with decomposed human cadavers. Significance and Impact of the Study: These findings enable tracing out the profile of fungal communities of human cadavers for the first time. However, much more research will be necessary to develop this new segment of mycology and to enable its routine use in forensic science.     

Comparative analysis of bacterial community and antibiotic-resistant strains in different developmental stages of the housefly (Musca domestica)

The housefly (Musca domestica) is an important host for a variety of bacteria, including some pathogenic and antibiotic-resistant strains. To further investigate the relationship between the housefly and the bacteria it harbors, it is necessary to understand the fate of microorganisms during the larval metamorphosis. The major bacterial communities in three developmental stages of the housefly (maggot, pupa, and adult fly) were investigated by a culture-independent method, polymerase chain reaction–denaturing gradient gel electrophoresis (PCR?DGGE) analysis of 16S rRNA genes. The bacteria that were identified using DGGE analysis spanned phyla Proteobacteria, Firmicutes, and Bacteroidetes. Changes in the predominant genera were observed during the housefly development. Bacteroides, Koukoulia, and Schineria were detected in maggots, Neisseria in pupae, and Macrococcus, Lactococcus, and Kurthia in adult flies. Antibiotic-resistant bacteria were screened using a selective medium and tested for antibiotic susceptibility. Most resistant isolates from maggots and pupae were classified as Proteus spp., while those from adult flies were much more diverse and spanned 12 genera. Among 20 tested strains across the three stages, 18 were resistant to at least two antibiotics. Overall, we demonstrated that there are changes in the major bacterial communities and antibiotic-resistant strains as the housefly develops.     

Effects of decomposition on carcass attendance in a guild of carrion-breeding flies

Many forensically important calliphorids, sarcophagids and muscids (Diptera) oviposit or larviposit on corpses only during the early stages of decomposition, yet individuals may attend bodies throughout decay. A field study was conducted to investigate how patterns of carcass use and attendance by some fly species are affected by decomposition. Five fly traps were placed in the forest and baited with whole, fresh piglet carcasses. Piglets decomposed in traps throughout the experiment, and all were skeletonized within 6 days. Flies were trapped at both early and late decomposition stages, and the species and population structures of trap catches were compared. More flies attended carcasses early rather than late in decay. For all species, flies attending early were mainly gravid females, but few gravid females attended late in decay. No females ovi- or larviposited late in decay, whereas females of all fly species deposited offspring early in decay. The number of males trapped of each species correlated positively with the number of females with eggs at early development stages. Observations were made of fly predation by European wasps Vespula germanica Fabricius (Hymenoptera, Vespidae) and jumper ants Myrmecia pilosula Smith (Hymenoptera, Formicidae) throughout the experiment. There was a higher risk for smaller fly species of being killed following predator attack. Ants and wasps attacked smaller fly species, whereas only wasps attacked larger fly species.     

Role of saprophagous fly biodiversity in ecological processes and urban ecosystem services

1. Direct consumption of organic matter by the saprophagous larvae provides the ecosystem with a fundamental service by recycling nutrients and reducing exposure to decomposing matter. The present study aimed to assess the functional role of saprophagous flies in the mass loss of different types of decomposing organic matter. 2. Two types of common urban waste were used to measure the role of flies in reducing organic matter: chicken viscera (chicken) and a mixture of flour and uncooked eggs (flour and eggs), representing leftover food. Ten traps baited with each substrate, under field conditions, allowed fly access (exposed to flies) and three traps from each substrate did not (unexposed controls); adult flies entering the traps or emerging from the substrates and substrate mass loss were recorded. 3. Species from Calliphoridae, Sarcophagidae, Muscidae, and Fanniidae families were collected mainly in traps baited with chicken, with Phoridae being the most abundant in traps with flour and eggs as bait. A significantly richer (P < 0.05) assemblage of fly species accessed the traps baited with chicken viscera (21 species) compared with those emerging (11 species), whereas similar numbers of species accessed (n = 5) or emerged (n = 1) from traps baited with flour and eggs (average richness accessing 7.97, emerging 2.83). Chicken substrate mass loss and species richness were positively related (r = 0.56, P = 0.001). In traps where richness was larger than 10 species, the substrates were reduced by more than 85% of their initial weight compared with unexposed controls, which lost 30%. Substrate mass loss significantly increased with the abundance of flies (r = 0.73, P < 0.0001). 4. The results of the present study support the functional role of saprophagous species diversity on the decomposition rates of organic matter, reinforcing the negative consequences of loss or gain of species in modified landscapes and for ecosystem function.     

Out of the Frying Pan and into the Fire: a Novel Trade-Off for Batesian Mimics

A mimicry system was investigated in which the models were ants (Formicidae) and both the mimics and the predators were jumping spiders (Salticidae). By using motionless lures in simultaneous‐presentation prey‐choice tests, how the predators respond specifically to the static appearance of ants and ant mimics was determined. These findings suggest a rarely considered adaptive trade‐off for Batesian mimics of ants. Mimicry may be advantageous when it deceives ant‐averse potential predators, but disadvantageous in encounters with ant‐eating specialists. Nine myrmecophagic (ant‐eating) species (from Africa, Asia, Australia and North America) and one araneophagic (spider‐eating) species (Portia fimbriata from Queensland) were tested with ants (five species), with myrmecomorphic (ant‐like) salticids (six species of Myrmarachne) and with non‐ant‐like prey (dipterans and ordinary salticids). The araneophagic salticid chose an ordinary salticid and chose flies significantly more often than ants. Portia fimbriata also chose the ordinary salticid and chose flies significantly more often than myrmecomorphic salticids. However, there was no significant difference in how P. fimbriata responded to ants and to myrmecomorphic salticids. The myrmecophagic salticids chose ants and chose myrmecomorphic salticids significantly more often than ordinary salticids and significantly more often than flies, but myrmecophagic salticids did not respond significantly differently to myrmecomorphic salticids and ants.     

Visual and Chemical Cues Used in Host Location and Acceptance by a Dipteran Parasitoid

Locating potential hosts for egg laying is a critical challenge in the life history of many insects. Female insects in several orders have evolved mechanisms to find hosts by using olfactory and visual signals derived from their hosts. We describe visual and chemical cues used by the dipteran parasitoid Apocephalus paraponerae (Diptera: Phoridae) in the location and acceptance of its host ant Paraponera clavata (Hymenoptera: Formicidae: Ponerinae). Our results show that A. paraponerae uses the visual cue of ant body size when locating hosts at short range and that these flies lay more eggs in ants that retain their surface chemicals than in ants with these chemicals removed. We compare the cues used by A. paraponerae with cues used by tephritid fruit flies in location and acceptance of their hosts, and we suggest further avenues for the study of host location, acceptance, and host discrimination of A. paraponerae and other parasitoids of ants.     

An unusual,but not unexpected,evolutionary step taken by syrphid flies: the first record of true primary parasitoidism of ants by Microdontinae

Parasitoidism of ants by flies is known only for Phoridae and Tachinidae. We report the first record of a hoverfly (Syrphidae, Microdontinae, Hypselosyrphus) acting as a true primary parasitoid of ants. Previously, larvae of Microdontinae were known only as obligate predators of ant brood. This is also the first host record for any Hypselosyrphus species, the first reliable record of an association between a syrphid fly and a ponerine ant, and the first record of a dipteran parasitoid developing upon the immature stages of ants. We reared adults of Hypselosyrphus trigonus from cocoons of the arboreal ponerine ant, Pachycondyla villosa, nesting in Aechmea bracteata bromeliads in southern Quintana Roo, Mexico, and we succeeded in determining various aspects of the parasitoid's life history. The findings obtained in the present study provide novel insights into the evolutionary transformation and diversification of the feeding habits of microdontine syrphid larvae, from an obligatory, specific predatory association with the ant brood, to parasitoidism of ant prepupae. We also highlight the need for more detailed studies of the interactions of arboreal ants and their parasites. We conclude with an overview of the evolutionary transitions and diversification of larval feeding habits that have taken place within the family Syrphidae. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 462–472.     

Lycaenids parasitizing symbiotic plant-ant partnerships

Summary Many species of the paleotropic plant genus Macaranga (Euphorbiaceae) live in symbiosis with the ant genus Cremastogaster (Myrmicinae), especially with C. borneensis. The ants protect their plants from many herbivorous enemies. The plants provide food-bodies and nesting space in the internodes. In addition the ants care for honeydew producing scale insects in these spaces. The caterpillars of several species of the genus Arhopala (Lycaenidae) parasitize on this symbiosis system. With the aid of their myrmecophilic organs the caterpillars overcome the aggressivity of the ants and feed on the Macaranga leaves without disturbance. Moreover the caterpillars and their pupae are protected against parasites and predators by the ants. As the female butterflies oviposit the eggs only in low numbers upon young leaves, the plants are not seriously affected.The larvae of the three Arhopala species; A. amphimuta, A. moolaiana, and A. zylda are adapted to their host plant species Macaranga triloba, M. hulletti, and M. hypoleuca by means of color, shape, and behavior. In addition, the different larval stages change their appearance according to the parts of the plant on which they feed and rest. These cryptic adaptations point to a distinct monophagy of these butterflies.The state of phylogenetic relationship within the three lycaenids is parallel to the relationship among the three host plants.This work was supported by the Deutsche Forschungsgemeinschaft. We are indebted to Mr. Eliot, Taunton, UK, for the identification of the lycaenids, for stimulating discussions and literature hints     

Size specific demography of three species of Anastrepha fruit flies

Individuals of three Anastrepha species: A. obliqua, A. ludens, and A. serpentina (Diptera: Tephritidae), were sorted according to pupal weight in cohorts of large and small flies. Demographic parameters and reproductive patterns and heterogeneity were determined for each cohort. Large flies of the three species presented greater expectation of life and gross fecundity rates. A. ludens was the species with the longest life span (expectation of life of large adults was 110 days) and the greatest gross fecundity rates (1597 eggs/female for the large flies). While, A. obliqua had the shortest mean age of reproduction (33 days), and the greatest daily egg production (14 eggs/female/day). Net fecundity was similar in these two. A. serpentina had lower fecundity rates.Reproductive information for each size and each species include: age-by-parity relations, fraction of sexually mature life in which females lay eggs, and frequency distribution of individual egg production. Results demonstrate that even under constant laboratory conditions and using standard artificial hosts, there is a great deal of life history variation among these Anastrepha species and among other tephritid fruit flies.     

Acceptability of Drosophila suzukii as prey for common predators occurring in cherries and berries

The invasive cherry vinegar fly, Drosophila suzukii, has been identified in Europe as a destructive fruit pest since its arrival in 2008. In the present laboratory study, three predatory insects (Orius majusculus, Chrysoperla carnea, and Forficula auricularia) naturally occurring on fruit crops in Europe were investigated for their ability to attack and feed on D. suzukii within and outside fruits. The predators were provided with various D. suzukii life stages (eggs, larvae, pupae or adults) exposed or within infested cherries. The anthocorid bug O. majusculus fed on eggs and larvae, but was not able to attack pupae. Larvae of the lacewing C. carnea preyed upon D. suzukii eggs, larvae and pupae and also captured adult flies. The European earwig F. auricularia was the most voracious predator of these three tested species. Although the earwigs were not able to catch adult flies, they readily preyed upon every other developmental stage. Adult O. majusculus or third instar larvae of C. carnea significantly reduced the offspring of D. suzukii from infested cherries, when these contained the egg stage of the pest. None of the predators were able to attack early larval stages inside the cherries. But pupae that protruded from the fruit epicarp or that had pupated outside the fruit were accessible to lacewing larvae and earwigs and significantly reduced by them. Orius bugs, lacewing larvae and earwigs were able, under laboratory conditions, to capture and prey upon various life stages of the invasive pest, if not completely concealed inside the fruit. Our findings suggest that these generalist predators may have some control capacity on infested fruit in cultivated fruit crops and also in non‐crop habitats.     

Parasitoids deter foraging by Argentine ants (Linepithema humile) in their native habitat in Brazil

The Argentine ant, Linepithema humile, has invaded sites across Africa, Australia, Europe, and North America. In its introduced ranges it eliminates native ants and tends agricultural pests. Few studies have examined the ecology of Argentine ants in their native habitat. This study examined the effects of parasitoid flies, genus Pseudacteon, on the foraging behavior of Argentine ants in part of their native range in southern Brazil. Pseudacteon parasitoids commonly attacked Argentine ants, but not other ant species, in daylight at temperatures above 18°C. Argentine ants abandoned food resources and returned underground in the presence of parasitoids. Parasitoid attack rates diminished as Argentine ants retreated underground. Where parasitoids were present, Argentine ants were abundant at food resources only during times of day when parasitoids were inactive. Where parasitoids were absent, Argentine ants were abundant at food resources throughout the day. Overall, the presence of parasitoids explained observed variation in Argentine ant foraging far better than temperature, although temperature had some effect. The results suggest that Pseudacteon parasitoids inhibit the ability of Argentine ants to gather food resources in their native habitat in Brazil. Received: 11 December 1997 / Accepted: 12 June 1998     

Fire ant myrmecophiles: feeding relationships ofMartinezia dutertrei andEuparia castanea (Coleoptera: Scarabaeidae) with their host ants,Solenopsis spp. (Hymenoptera: Formicidae)

Summary Feeding relationships of adultEuparia castanea Serville andMartinezia dutertrei Chalumeau with their ant hosts were studied in the laboratory using the radioactive tracer³²P.Euparia castanea was tested withSolenopsis geminata (F.),Martinezia dutertrei Chalumeau was tested withS. invicta Buren,S. richteri Forel, andS. geminata. Unlabeled beetles were exposed to various radioisotope labeled conditions for 24 hr and then checked for acquired radioactivity. In whole colony tests, both species of beetles acquired radioactivity.M. dutertrei obtained food from live ants, butE. castanea did not. Both species of beetles ate ant larvae.E. castanea also obtained food from ant larvae by strigilation. Neither species of beetle fed on ant feces or other secretions on the substrate. Both species of beetles obtained food by strigilation from fresh and decomposed worker ant cadavers.M. dutertrei also ate both kinds of ant cadavers. Both species of beetles also ate dead house flies, indicative of scavenging or feeding on ant booty.Martinezia dutertrei showed no preference for any particular ant species. Ants did not obtain food by trophallaxis or glandular secretion from either species of beetle. Martinezia dutertrei Chalumeau, 1983 (=Myrmecaphodius excavaticollis Auct.,nec Blanchard 1843).This article reports the results of research only. Mention of a proprietary product does not constitute an endorsement or a recommendation for its use by the U.S. Department of Agriculture.     

A mycosis of the black fly Simulium decorum (Simuliidae) caused by Erynia curvispora (Entomophthoraceae)

Adult black flies (Simulium decorum) that succumbed to infections caused by Erynia curvispora (= Entomophthora curvispora) were found in Ithaca, New York. Other than hyphal elements of the fungus, the only recognizable structures found within most cadavers were remnants of the tracheal system. Several female cadavers contained well developed eggs. A few males contained shrivelled testes. Germination of primary conidia produced: 1, secondary conidia similar to the primaries or; 2, rounded secondary conidia or; 3, very long germ tubes. In vitro culture of E. curvispora was achieved but its ability to sporulate and to grow vegetatively gradually disappeared. Insectary-reared S. vittatum and S. pictipes were experimentally infected by conidia from in vitro cultures in the laboratory. The incubation period of the disease under these conditions was about six days. In nature the mycosis not only decreases the life expectancy of black flies but probably limits their egg-producing capabilities as well. The mycosis probably compromises the fly's ability to vector filarial worms that cause diseases of man and other mammals.