Mouthpart homologies and life habits of Mesozoic long-proboscid scorpionflies.

Mesozoic long-proboscid scorpionflies (Mesopsychoidea) provide important clues to ancient plant-pollinator interactions. Among them, the family Aneuretopsychidae is especially important because its mouthparts are vital to deciphering the early evolution of Mesopsychoidea and putatively the origin of fleas (Siphonaptera). However, the identification of mouthpart homologs among Aneuretopsychidae remains controversial because of the lack of three-dimensional anatomical data. Here, we report the first Aneuretopsychidae from Late Cretaceous Burmese amber, which have short maxillary palpi and elongate mouthpart elements consisting of one pair of galeae and one hypopharynx. Their mouthparts are identical to those of Pseudopolycentropodidae (= Dualulidae, new synonym) but are not homologous to those of Siphonaptera. Our phylogenetic analysis provides robust evidence for the debated monophyly of Mesopsychoidea. Our results suggest that the long-proboscid condition has most likely evolved once in Mesopsychoidea, independently from fleas, and further reveal the variety and complexity of mid-Cretaceous pollinating insects.

Species-level identification of the blowfly Chrysomya megacephala and other Diptera in China by DNA barcoding.

The blowfly Chrysomya megacephala, or oriental latrine fly, is the most common human-associated fly of the oriental and Australasian regions. Chrysomya megacephala is of particular interest for its use in forensic entomology and because it is a disease vector. The larvae are economically important as feed for livestock and in traditional Chinese medicine. Identification of adults is straightforward, but larvae and fragments of adults are difficult to identify. We collected C. megacephala, its allies Chrysomya pinguis and Protophormia terraenovae, as well as flies from 11 other species from 52 locations around China, then sequenced 658 base pairs of the COI barcode region from 645 flies of all 14 species, including 208 C. megacephala, as the basis of a COI barcode library for flies in China. While C. megacephala and its closest relative C. pinguis are closely related (mean K2P divergence of 0.022), these species are completely non-overlapping in their barcode divergences, thus demonstrating the utility of the COI barcode region for the identification of C. megacephala. We combined the 208 C. megacephala sequences from China with 98 others from public databases and show that worldwide COI barcode diversity is low, with 70% of all individuals belonging to one of three haplotypes that differ by one or two substitutions from each other, reflecting recent anthropogenic dispersal from its native range in Eurasia.

New species and revisions of Pediciidae (Diptera) from the Middle Jurassic of northeastern China and Russia.

Two new species of Praearchitipula Kalugina, 1985, P. apprima sp. nov. and P. mirabilis sp. nov., are described and illustrated from the late Middle Jurassic Jiulongshan Formation of Daohugou in eastern Inner Mongolia, China. In addition, we propose to transfer Architipula abnormis Hao & Ren, 2009 (which is from the same locality of Daohugou) from Architipula of Limoniidae to Praearchitipula of Pediciidae: Praearchitipula abnormis (Hao & Ren, 2009) comb. nov. In addition, we propose to transfer Praearchitipula spasskia Kalugina, 1985 to the genus Mesotipula (Limoniidae, Architipulinae). We also suggest treating Praearchitipula lata Kalugina, 1985 as a junior synonym of Praearchitipula notabilis Kalugina, 1985. An emended generic diagnosis of Praearchitipula is provided.

Notoatherix antiqua gen. et sp. nov., first fossil water snipe fly from the Late Jurassic of Australia (Diptera: Athericidae).

The first water snipe fly (Diptera: Tabanomorpha) fossil discovered in the Late Jurassic Talbragar Fish Bed in Australia is described and illustrated. Notoatherix antiqua gen. et sp. nov., described from a single wing specimen, is assigned to the family Athericidae based on the diagnostic feature of this family: the vein R2+3 ending very near to R1 (marginal cell closed). It is the first record of Athericidae from Australia and the oldest adult record of this family worldwide.

Conserved metallomics in two insect families evolving separately for a hundred million years.

Μetal cofactors are required for enzymatic catalysis and structural stability of many proteins. Physiological metal requirements underpin the evolution of cellular and systemic regulatory mechanisms for metal uptake, storage and excretion. Considering the role of metal biology in animal evolution, this paper asks whether metal content is conserved between different fruit flies. A similar metal homeostasis was previously observed in Drosophilidae flies cultivated on the same larval medium. Each species accumulated in the order of 200 µg iron and zinc and approximately ten-fold less manganese and copper per gram dry weight of the adult insect. In this paper, data on the metal content in fourteen species of Tephritidae, which are major agricultural pests worldwide, are presented. These fruit flies can be polyphagous (e.g., Ceratitis capitata) or strictly monophagous (e.g., Bactrocera oleae) or oligophagous (e.g., Anastrepha grandis) and were maintained in the laboratory on five distinct diets based on olive oil, carrot, wheat bran, zucchini and molasses, respectively. The data indicate that overall metal content and distribution between the Tephritidae and Drosophilidae species was similar. Reduced metal concentration was observed in B. oleae. Feeding the polyphagous C. capitata with the diet of B. oleae resulted in a significant quantitative reduction of all metals. Thus, dietary components affect metal content in some Tephritidae. Nevertheless, although the evidence suggests some fruit fly species evolved preferences in the use or storage of particular metals, no metal concentration varied in order of magnitude between these two families of Diptera that evolved independently for over 100 million years.

Two new species of Mesoplecia (Insecta: Diptera: Protopleciidae) from the late Middle Jurassic of China.

Two new species of Mesoplecia Rohdendorf, 1938, M. plena sp. nov. and M. fastigata sp. nov., are described from the late Middle Jurassic Jiulongshan Formation of Daohugou, Inner Mongolia, China. Based on the emended generic diagnosis of Mesoplecia by Zhang in 2007, these two new species are assigned to Mesoplecia by a combination of the following five characters: (1) Head small; (2) Vein bRs not more than twice as long as dRs; (3) M1, M2 at least 5 times as long as dM1+2; (4) bM1+2 longer than dM1+2; and (5) Legs with coxae and femora thick. In addition, a key to Mesoplecia is provided. 

Caught in the act: pollination of sexually deceptive trap-flowers by fungus gnats in Pterostylis (Orchidaceae).

BACKGROUND AND AIMS: Pterostylis is an Australasian terrestrial orchid genus of more than 400 species, most of which use a motile, touch-sensitive labellum to trap dipteran pollinators. Despite studies dating back to 1872, the mechanism of pollinator attraction has remained elusive. This study tested whether the fungus gnat-pollinated Pterostylis sanguinea secures pollination by sexual deception. METHODS: The literature was used to establish criteria for confirming sexual deception as a pollination strategy. Observations and video recordings allowed quantification of each step of the pollination process. Each floral visitor was sexed and DNA barcoding was used to evaluate the degree of pollinator specificity. Following observations that attraction to the flowers is by chemical cues, experimental dissection of flowers was used to determine the source of the sexual attractant and the effect of labellum orientation on sexual attraction. Fruit set was quantified for 19 populations to test for a relationship with plant density and population size. KEY RESULTS: A single species of male gnat (Mycetophilidae) visited and pollinated the rewardless flowers. The gnats often showed probing copulatory behaviour on the labellum, leading to its triggering and the temporary entrapment of the gnat in the flower. Pollen deposition and removal occurred as the gnat escaped from the flower via the reproductive structures. The labellum was the sole source of the chemical attractant. Gnats always alighted on the labellum facing upwards, but when it was rotated 180 ° they attempted copulation less frequently. Pollination rate showed no relationship with orchid population size or plant density. CONCLUSIONS: This study confirms for the first time that highly specific pollination by fungus gnats is achieved by sexual deception in Pterostylis. It is predicted that sexual deception will be widespread in the genus, although the diversity of floral forms suggests that other mechanisms may also operate.

Conspecific and heterospecific plant densities at small-scale can drive plant-pollinator interactions.

Generalist pollinators are important in many habitats, but little research has been done on small-scale spatial variation in interactions between them and the plants that they visit. Here, using a spatially explicit approach, we examined whether multiple species of flowering plants occurring within a single meadow showed spatial structure in their generalist pollinator assemblages. We report the results for eight plant species for which at least 200 individual visits were recorded. We found that for all of these species, the proportions of their general pollinator assemblages accounted for by particular functional groups showed spatial heterogeneity at the scale of tens of metres. This heterogeneity was connected either with no or only subtle changes of vegetation and flowering species composition. In five of these species, differences in conspecific plant density influenced the pollinator communities (with greater dominance of main pollinators at low-conspecific plant densities). The density of heterospecific plant individuals influenced the pollinator spectrum in one case. Our results indicate that the picture of plant-pollinator interactions provided by averaging data within large plots may be misleading and that within-site spatial heterogeneity should be accounted for in terms of sampling effort allocation and analysis. Moreover, spatially structured plant-pollinator interactions may have important ecological and evolutionary consequences, especially for plant population biology.

Divergence of Eurosta solidaginis in response to host plant variation and natural enemies.

We tested the hypothesis that forest and prairie populations of the gall-inducing fly, Eurosta solidaginis, have diverged in response to variation in selection by its host plant Solidago altissima, and its natural enemies. A reciprocal cross infection design experiment demonstrated that fly populations from the prairie and forest biomes had higher survival on local biome plants compared to foreign biome host plants. Flies from each biome also had an oviposition preference for their local plants. Each fly population induced galls of the size and shape found in their local biome on host plants from both biomes indicating a genetic basis to the differences in gall morphology. Solidago altissima from the prairie and forest biomes retained significant morphological differences in the common garden indicating that they are genetically differentiated, possibly at the subspecies level. The populations are partially reproductively isolated as a result of a combination of prezygotic isolation due to host-associated assortative mating, and postzygotic isolation due to low hybrid survival. We conclude that E. solidaginis is undergoing diversifying selection to adapt to differences between prairie and forest habitats.

[Shapes, properties and microstructures of gadfly].

OBJECTIVE: To search and identify the microstructure of medicinal properties of six kinds of gadfly. METHOD: The medicinal properties, different body parts and bristles microscopic characteristics were compared. RESULT: The two-spotted yellow gadfly had a smaller size. Its length no more than 14 mm, body wall debris was yellow brown or pale yellow, the seta was smaller than that of the other gadflies; while the other five varieties' body lengths all exceeded 15 mm, and their body wall debris mostly were brown black or gray and black. CONCLUSION: The authentication between the two-spotted yellow gadfly and the other five varieties can be made by the microscopic characteristics of their medicinal properties, body wall debris colors, bristle lengths, and basal diameters.

A preliminary study on the decomposition and dipteran associated with exposed carcasses in an oil palm plantation in Bandar Baharu, Kedah, Malaysia.

This study was carried out in an oil palm plantation in Bandar Baharu, Kedah using monkey carcasses and focuses in documenting the decomposition and dipteran colonization sequences in 50 days. This is the first study of Diptera associated with the exploitation of carcasses conducted in the north of peninsular Malaysia during the dry and wet seasons thereat. During the process of decomposition in both seasons, five phases of decay were recognized namely fresh, bloated, active decay, advance decay and dry remain. In this decomposition study, biomass loss of carcass occurred rapidly during the fresh to active decay stage due to the colonization and feeding activity of the Diptera larvae. The duration of the fresh and bloated stages of decay were the same in wet and dry seasons but later stages of decay were markedly shorter during the wet season. Twenty one species of adult Diptera were identified colonizing carcasses in the study period. Among the flies from the family Calliphoridae, Chrysomya megacephala Fabricius and Chrysomya nigripes Aubertin were recognized as the earliest arrivals on the first day of exposure. Adult Ch. nigripes was abundant for approximately two weeks after placement of the carcasses. By comparing the percentages of adults collected during the study period, the calliphorids abundance in percentages in wet season was 50.83%, but in dry season, the abundance was only about 35.2%. In contrast, the percentage of Sphaeroceridae in wet season was only 3.33%, but in the dry season, the abundance was 20.8%. Dipteran in family Phoridae, Piophilidae, Sepsidae, Drosophilidae and Dolichopodidae colonized the carcasses for a long period of time and were categorized as long term colonizers.

Insect succession on a decomposing piglet carcass placed in a man-made freshwater pond in Malaysia.

This entomological study was conducted in a man-made freshwater pond in a palm oil plantation in Tanjung Sepat, Selangor from 23 July 2007 by using pig (Sus scrofa) as a carcass model. A 1.5 month old piglet (5 kg), which died of asphyxia after being accidentally crushed by its mother, was thrown into a pond. Observation was made for ten days; one visit per day and climatological data were recorded. On the first two days, the piglet carcass sunk to the bottom of the pond. The carcass floated to the surface on the third day but no fly activities were seen. The blow fly, Chrysomya megacephala and Chrysomya rufifacies started to oviposit on the fourth day. Other than adult flies, a spider (Arachnida) was also observed on the carcass. Bubbles accumulated at the mouthpart, and the abdomen was greenish black. A lot of blow fly eggs were seen on the body surface on the fifth day (floating decay), along with first and second instars C. megacephala crawling under the piglet's skin. On the sixth day, adult blow fly, C. megacephala,and C. rufifacies,and muscid flies, Ophyra spinigera and Musca domestica were observed on to the carcass. High numbers of first and second instars of flies were observed wandering around the body surface with C. megacephala larvae being the predominant species. Two prominent maggot masses occurred on seventh and eighth days. Bloated deterioration stage began on day eighth exposing rib bones, humerus bones and intestines. Carcass was partially sinking and the maggot masses were at the water level. On day ninth, the carcass was partially sinking and three maggot masses were observed on the exposed surface. There were very few adult flies, including a scarab beetle was sighted on the carcass at this stage. The carcass along with the maggots sunk on day tenth, leaving an oily layer on the water surface.

A preliminary study of insect succession on a pig carcass in a palm oil plantation in Malaysia.

This preliminary study was carried out in a palm oil plantation in Tanjung Sepat, Selangor in 17 May 2007 by using pig (Sus scrofa) as a carcass model in forensic entomological research. A 3 month old pig (8.5 kg) that died of pneumonio was placed in the field to observe the decomposition stages and the fauna succession of forensically important flies. Observation was made for two weeks; two visits per day and all climatological data were recorded. The first visitor to the pig carcass was a muscid fly, seen within a minute, and followed by ants and spiders. Within half an hour, calliphorid flies came over. On the second day (fresh), few calliphorid and sarcophagid flies were found on the carcass. Two different species of moths were trapped in the hanging net. The first larva mass occurred on the third day (bloated) around the mouthpart, with some L1 and L2 found in the eyes. Reduvid bugs and Staphylinidae beetles were recovered on the fourth day (active decay), and new maggot masses occurred in the eyes and anus. L3 larvae could be found beneath the pig carcass on the fourth day. On the fifth day (active decay), new maggot masses were found on neck, thorax, and hind legs. Advance decay occurred on the sixth day with abundant maggots covering all over the body. The main adult fly population was Chrysomya megacephala (day 2 to day 6), but the larvae population was mainly those of Chrysomya rufifacies (day 4 to day 14). The dry stage began on the eighth day. Hermetia illucens adult was caught on day-13, and a larvae mass of Chrysomya rufifacies was seen burrowing under the soil. This forensic entomological research using pig carcass model was the first record in this country.

Ophthalmomyiasis in Kuwait: first report of infections due to the larvae of Oestrus ovis before and after the Gulf conflict.

We report for the first time four cases of ophthalmomyiasis due to the larvae of Oestrus ovis in Kuwait, before and after Operations Desert Shield and Desert Storm. The larvae were easily removed under local anaesthetic. The symptom complex of acute foreign body sensation, irritation, redness, lacrimation and photophobia resolved rapidly. Ophthalmic antibiotic and corticosteroid drops were also instilled and recovery was uneventful. The ophthalmomyiasis may not always be associated with contact with sheep-rearing per se. Medical personnel should therefore be aware that in cases of what might appear initially as acute, non-specific catarrhal conjunctivitis, patients with the persistent symptom complex should be re-examined to exclude ophthalmomyiasis due to the larvae of O. ovis in endemic areas.