Determinants of abundance and effects of blood-sucking flying insects in the nest of a hole-nesting bird

Compared to non-flying nest-dwelling ectoparasites, the biology of most species of flying ectoparasites and its potential impact on avian hosts is poorly known and rarely, if ever, reported. In this study we explore for the first time the factors that may affect biting midge (Diptera: Ceratopogonidae) and black fly (Diptera: Simuliidae) abundances in the nest cavity of a bird, the hole-nesting blue tit Cyanistes caeruleus, and report their effects on adults and nestlings during reproduction. The abundance of biting midges was positively associated with nest mass, parental provisioning effort and abundance of blowflies and black flies, while negatively associated with nestling condition. Furthermore, a medication treatment to reduce blood parasitaemias in adult birds revealed that biting midges were more abundant in nests of females whose blood parasitaemias were experimentally reduced. This finding would be in accordance with these insect vectors attacking preferentially uninfected or less infected hosts to increase their own survival. The abundance of black flies in the population was lower than that of biting midges and increased in nests with later hatching dates. No significant effect of black fly abundance on adult or nestling condition was detected. Blood-sucking flying insects may impose specific, particular selection pressures on their hosts and more research is needed to better understand these host–parasite associations.     

Bloodsucking midges from the nests of birds in the foothills of Western Sikhote-Alin

The specific composition and number of midges in nest biotopes of birds of forest formations of Western Sikhote-Alin are given. 17 species of the genus Culicoides were found to attack 17 species of birds during the nesting period. The number of midges in nests depends both on the biotopical distribution of nests and mode of living of birds and on the total number of midges in nature. The most high percentage of females engorged with blood at nests was recorded in the obsoletus group, which is most abundant on man and at nests of birds of anthropogenic complex.     

The intensity and efficiency of a gadfly attack on cattle depending on the number and location of the animals in the herd

The effect of group was studied on cattle being attacked by horse flies of three genera. The method of simultaneous registrations of attacking horse flies in herds of 8 to 100 animals and on single cows was used. It has been shown that the effect of group reveals itself only when animals in the herd reach a certain minimum number, the effect rate depending on peculiarities of attacking of a given species of bloodsuckers, such as a part of responding individuals, distance of an attack, duration of contact with an object. These parameters tend to change with increasing number of animals in the herd. Therefore differences in the intensity of attacks on herds with different cattle stock cannot be explained proceeding only from differences in the occupied areas. The number of attacking horse flies decreases from the periphery of the herd to its centre and is not the same in different parts of the periphery. The effectiveness of attacking, ie the part of sucking individuals of a given species (genus) from the number of horse flies attacking for a definite period of time, is the highest in a large herd and increases in its ranges from the periphery to the centre. This dependence leads to a more even distribution of sucking individuals as compared to attacking ones.     

THE IDENTITY OF THE SWEDE MIDGE, WITH NOTES ON ITS BIOLOGY

A brief historical summary is given of the literature concerning Contarinia nasturtii Kieffer, C. torquens de Meijere and C. geisenheyneri Riibsaamen, three gall midges (Cecidomyidae) which have been associated respectively with leaf damage on Brassica spp. in England, identical malformation on the Continent and swollen and closed flowers of Brassica spp. in Europe.
Following the discovery in England of the true Contarinia nasturtii causing swollen and closed flowers oiRorippa amphibia, preliminary experiments have shown that midges from this source will also cause similar damage to swede flowers and that they are the same species as those attacking R. amphibia blossom in the Netherlands.
Further preliminary experiments have shown that swede midge derived from rape leaf axils will also cause identical damage to radish flowers in addition to breeding successfully on the leaves of turnip, swede, cabbage and radish.
Male midges derived from Rorippa blossom have been mated with females from rape leaf axils, and their offspring have been reared on Rorippa flowers and on turnip leaves.
This biological evidence confirms the previous supposition based on morphological grounds that the swede midge is Contarinia nasturtii Kieffer and will cause either flower or leaf damage. Consequently, C. torquens de Meijere and C. geisenheyneri Riibsaamen must remain synonyms.
The shortest time for a generation (from parent to first offspring midge) to develop was 24–39 days in an unheated open glasshouse during June-July in 1949 at Harpenden. Under the same conditions, the shortest time for the next generation from late July to August was 29–32 days. C. nasturtii is the first Contarinia species in which unisexual families have been discovered.     

Development and evaluation of real‐time PCR assays for bloodmeal identification in Culicoides midges

Culicoides (Diptera: Ceratopogonidae) midges are the biological vectors of a number of arboviruses of veterinary importance. However, knowledge relating to the basic biology of some species, including their host‐feeding preferences, is limited. Identification of host‐feeding preferences in haematophagous insects can help to elucidate the transmission dynamics of the arboviruses they may transmit. In this study, a series of semi‐quantitative real‐time polymerase chain reaction (qPCR) assays to identify the vertebrate host sources of bloodmeals of Culicoides midges was developed. Two pan‐reactive species group and seven species‐specific qPCR assays were developed and evaluated. The assays are quick to perform and less expensive than nucleic acid sequencing of bloodmeals. Using these assays, it was possible to rapidly test nearly 700 blood‐fed midges of various species from several geographic locations in Australia.     

Latitudinal diversity of biting midge species within the Obsoletus group across three habitats in Europe

Culicoides species from the Obsoletus group are important vectors of bluetongue and Schmallenberg virus. This group consists of several species that cannot easily be identified using morphological characteristics. Therefore, limited information is available about their distribution and habitat preferences. In this study, we aimed to elucidate the species composition of the Obsoletus group in three habitat types at climatically different latitudes across Europe. Traps were placed in three habitat types in three countries at different latitudes. After DNA extraction, biting midges were identified using PCR and gel electrophoresis. Extraction of DNA using Chelex proved to be a cost and time efficient method for species identification. A latitudinal effect on the relative abundance of species from the Obsoletus group was found. Species composition was unique for most country‐habitat combinations. The majority of biting midges were either C. obsoletus s.s. or C. scoticus, and both species were found at all latitudes and habitats. Their wide distribution and their high abundance at livestock farms make these species likely candidates for rapid farm‐to‐farm transmission of pathogens throughout Europe. Our results emphasize the need to differentiate Obsoletus group species to better understand their ecology and contribution to pathogen transmission.     

五种库蠓脂肪酸的研究

本文用气相色语法分析了不显库蠓(Culicoides obsoletus)、兴安库蠓(C, sinanoensis)、怒江库蠓(C.Nujiangensis)、灰黑库蠓(C.Pulicaris)和刺整库蠓(C.Punctatus)等5种库蠓雌虫脂 肪醛的组成和含量。 结果表明,5种库蠓均含有12-14种主要脂肪酸,并以棕榈油酸(C_16：1)、棕搁酸 (C_16：0)、油酸(C_18：1)、硬脂酸(C_18：0)含量最高,共占脂肪酸总量的70%以上。对主要脂肪酸的含量进行聚类分析,发现不显库蠓种团内任意两种库蠓间的欧氏距离小于不显库蠓种团种类与灰黑库蠓种团种类间的欧氏距离,说明脂肪酸的定性、定量分析结果对库蠓分类有一定的参考价值。     

Acoustic Preference of Frog‐Biting Midges (Corethrella spp) Attacking Túngara Frogs in their Natural Habitat

In many animals, males aggregate to produce mating signals that attract conspecific females. These leks, however, also attract eavesdropping predators and parasites lured by the mating signal. This study investigates the acoustic preferences of eavesdroppers attracted to natural choruses in a Neotropical frog, the túngara frog (Engystomops pustulosus). In particular, we examined the responses of frog‐biting midges to natural variation in call properties and signaling rates of males in the chorus. These midges use the mating calls of the frogs to localize them and obtain a blood meal. Although it is known that the midges prefer complex over simple túngara frog calls, it is unclear how these eavesdroppers respond to natural call variation when confronted with multiple males in a chorus. We investigated the acoustic preference of the midges using calling frogs in their natural environment and thus accounted for natural variation in their call properties. We performed field recordings using a sound imaging system to quantify the temporal call properties of males in small choruses. During these recordings, we also collected frog‐biting midges attacking calling males. Our results revealed that, in a given chorus, male frogs calling at higher rates and with higher call complexity attracted a larger number of frog‐biting midges. Call rate was particularly important at increasing the number of midges attracted when males produced calls of lower complexity. Similarly, call complexity increased attractiveness to the midges especially when males produced calls at a low repetition rate. Given that female túngara frogs prefer calls produced at higher repetition rates and higher complexity, this study highlights the challenge faced by signalers when increasing attractiveness of the signal to their intended receivers.     

西藏蠓类名录、地理分布及区系分析(双翅目,蠓科)

根据1987年以来野外调查资料,分析了西藏已知蠓类种类、地理分布及区系特点。目前已知西藏蠓科昆虫4亚科14属31亚属151种,占我国已知蠓类(约1100种)的13.73%。其中,仅在西藏有分布并以西藏为模式产地的特有种为99种,占西藏已知蠓种的65.56%。区系分析表明,在所报道的西藏蠓科151种中,古北界15种,占西藏蠓种总数的9.93%,均分布于青藏区青海藏南亚区;东洋界131种,占西藏蠓种总数的86.75%,有105种分布于西南区喜马拉雅亚区,有18种分布于西南区西南山地亚区,有8种分布于喜马拉雅亚区和西南山地亚区;两界均有分布的有5种,占西藏蠓种总数的3.31%。     

两种稻田摇蚊采集方法的比较

本文介绍了一种较为简便和节省人工的稻田摇蚊田间取样方法:笼罩法,并将笼罩法得到的稻田摇蚊群落结构和发生动态和吸虫器法得到的结果进行了比较。研究结果表明:在水稻的4个生育期中,笼罩法和吸虫器法均采集到了中华摇蚊Chironomus sinicus Kiknadze,Wang,Istomina&Gunderina;台湾长跗摇蚊Tanytarsus formosanus Kieffer;云集多足摇蚊Polypedilum nubifer Skuse和刺铗长足摇蚊Tanypus puncitpennis Meigen,而吸虫器法还采集到微小沼摇蚊Limnophyes minimus Meigen。其中中华摇蚊和台湾长跗摇蚊为优势类群,笼罩法取样得到的两种优势种种群密度均高于吸虫器法的,例如在拔节期时笼罩法取样得到台湾长跗摇蚊的种群密度是吸虫器法的22倍。通过取样变异系数的比较发现,两种方法精确性都并不理想,在今后的试验中可以通过增加取样的样点量或取样面积来提高精确度。相比较而言吸虫器法操作复杂,而且较为耗时,在实际操作中往往受到一定条件的限制,而笼罩法则具有操作简便、准确度高等优点,试验安排可以进行高频率取样,能够更准确地反映田间摇蚊的种群动态。因此,笼罩法为以后研究与摇蚊生活习性相似的稻田节肢动物类群(如蚊科昆虫)提供了一种新的取样方案。     

Midges of the genus Culicoides (Ceratopogonidae) and an evaluation of the critical level of their population that bothers humans

The fauna of some species of the genus Culicoides in the forests of the Novgorod region was studied. The method of calculatin "on person" has shown that C. riethi and C. punctatus are dominant species. The critical level of abundance of midges disturbing people in recreation areas was determined (6 to 10 bites of C. riethi midges for 15 minutes). It was noted that people avoided recreation areas if the number of bites was over 40 for 15 minutes of calculation "on person".     

Abundance,diversity and temporal activity of adult Culicoides spp. associated with cattle in West Bengal,India

Relative abundance, species composition and temporal activity of Culicoides midges were studied for a period of 2 years (2012–2014) using suction ultra violet light traps at two sites located in the agriculture heartland of West Bengal, India. Surveillance in close proximity to cattle recorded predominance of five species with C oxystoma and C. peregrinus as the most dominant species followed by C. fulvus, C. innoxius and C. anophelis. The temporal activity of midges was investigated for seven consecutive nights at one site in August-September, 2012 and the predominant species was Culicoides oxystoma followed by Culicoides peregrinus. All of the species exhibited crepuscular activity with their flight activity increasing from dusk to dawn. Engorged adults constituted dominant age group in collections. Studies on population ecology of the adults midges are of considerable importance predicting for the epidemicity of midge-borne diseases in cattle.     

Discovery of cryptic diversity in phytophagous gall midges (Diptera: Cecidomyiidae) associated with different ecotypes of the perennial herb Cimicifuga simplex

Studying the diversification patterns of species-rich phytophagous insect taxa can help us understand the factors that cause species diversification. We conducted a molecular phylogenetic analysis of the mitochondrial COI gene of larvae of gall midges (Diptera: Cecidomyiidae) using three genetically differentiated morphs of Cimicifuga simplex plants and found that the gall midges could be divided into five major clades. Gall midges collected from morph I of C. simplex belonged to four Schizomyia clades. Gall midges collected from morph II of C. simplex belonged to one of the four Schizomyia clades collected from morph I. Gall midges collected from morph III belonged one Contarinia clade. On morphs I and II of C. simplex, the Schizomyia species induced galls on the flower bud, whereas on morph III of C. simplex, the Contarinia species was collected from normal fruits (not gall inducer); thus, morph III plants were used differently by gall midges than plants of morphs I and II. These results indicate that the cryptic diversity of these phytophagous insects correspond to that of plant ecotypes, and suggests that the diversification of the host plant contributed to parallel diversification of the phytophagous gall midges.     

DNA sequence variation in the ITS-1 rDNA subunit and host relationships in sorghum midge, Stenodiplosis sorghicola (Coquillett) (Diptera: Cecidomyiidae), in Australia

Sequence variation in the internal transcribed spacer (ITS-1) ribosomal DNA subunit was examined for sorghum midge obtained from introduced and native hosts in south-eastern and central Queensland. No variation was observed relative to host plant or geographical distance for midges collected from two introduced hosts, grain sorghum ( Sorghum bicolor ) and Johnson grass ( S. halepense ); however, sequence differences were observed between midges from introduced and native hosts and among midges from a single native host, slender bluegrass ( Dichanthium affine ). No evidence was observed of introduced midges on native hosts, or vice versa. These results agree with previously hypothesised host distributions for native and introduced midges in Australia, and expand the sample of introduced hosts to include Johnson grass. They suggest that Stenodiplosis sorghicola , the principal midge infesting grain sorghum, is also the most common species on Johnson grass. This confirms that Johnson grass plays a role in the population dynamics of S. sorghicola and suggests that midges originating from Johnson grass may influence levels of infestation in grain sorghum.     

Identification of field-caught Culicoides biting midges using matrix-assisted laser desorption/ionization time of flight mass spectrometry

Culicoides biting midges are of great importance as vectors of pathogens and elicitors of allergy. As an alternative for the identification of these tiny insects, matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) was evaluated. Protein mass fingerprints were determined for 4-5 field-caught reference (genetically confirmed) individuals of 12 Culicoides species from Switzerland, C. imicola from France, laboratory-reared C. nubeculosus and a non-biting midge. Reproducibility and accuracy of the database was tested in a validation study by analysing 108 mostly field-caught target Culicoides midges and 3 specimens from a non-target species. A reference database of biomarker mass sets containing between 24 and 38 masses for the different species could be established. Automated database-based identification was achieved for 101 of the 108 specimens. The remaining 7 midges required manual full comparison with the reference spectra yielding correct identification for 6 specimens and an ambiguous result for the seventh individual. Specimens of the non-target species did not yield identification. Protein profiling by MALDI-TOF, which is compatible with morphological and genetic identification of specimens, can be used as an alternative, quick and inexpensive tool to accurately identify Culicoides biting midges collected in the field.     

Flower heating following anthesis and the evolution of gall midge pollination in Schisandraceae

? Premise of the study: Flower heating is known from a few species in 11 of the c. 450 families of flowering plants. Flowers in these families produce heat metabolically and are adapted to beetles or flies as pollinators. Here, we focus on the Schisandraceae, an American/Asian plant family known to exhibit flower heating in some species, but not others, raising the question of the adaptive function of heat production. ? Methods: We used field observations, experiments, and ancestral trait reconstruction on a molecular phylogeny for Schisandraceae that includes the investigated species. ? Key results: At least two Chinese species of Illicium are exclusively pollinated by gall midges that use the flowers as brood sites (not for pollen feeding). Continuous monitoring of flower temperatures revealed that the highest temperatures were attained after the flowers' sexual functions were over, and experiments showed that post-anthetic warming benefited larval development, not fruit development. Midge larvae in flowers with trimmed tepals (and hence a lower temperature) died, but fruit set ratios remained unchanged. Based on the DNA phylogeny, gall midge pollination evolved from general fly/beetle pollination several times in Schisandraceae, with some species adapted to flower-breeding midges, others to pollen-feeding midges. ? Conclusions: Flower heating may be an ancestral trait in Schisandraceae that became co-opted in species pollinated by flower-breeding midges requiring long-persistent warm chambers for larval development.     

Identity and phylogenetic status of two sibling gall midge species (Diptera: Cecidomyiidae: Contarinia) on the perennial herb Vincetoxicum hirundinaria

Abstract Contarinia comprises one of the largest genera among gall forming midges of Cecidomyiidae, where identification and species relationships are uncertain. Using data on phenological development, morphometric relationships and mitochondrial DNA, the status of two isomorphic species, C. vincetoxici and C. asclepiadis , which attack the perennial herb Vincetoxicum hirundinaria , were investigated. Data show that they are two distinct species. In rearing experiments, the two gall midges were shown to have different times of adult emergence. Small differences in wing morphology were revealed that separate the two species from each other, as well as from C. loti , the type species of Contarinia . Sequence differences in the mitochondrial cytochrome b gene corroborate the specific status of C. vincetoxici and C. asclepiadis . Furthermore, a phylogenetic analysis, also including three other Contarinia species, showed that the two gall midges on V. hirundinaria are not even the most closely related species, suggesting two separate evolutionary colonizations of the host plant.     

垂叶榕果内寄生瘿蚊的发生规律

在云南西双版纳热带地区,一种还未被描述属和种的瘿蚊寄生于垂叶榕果内的雌花子房里,并膨大形成虫瘿,靠取食花胚组织完成发育.通过2010年定时定点的系统观察和研究瘿蚊的发生规律,结果发现:该种瘿蚊在垂叶榕上发生频率较高,抽样的18批果有17批被瘿蚊寄生,其中有13批果的寄生比率超过了60％,部分甚至达到100％.瘿蚊寄生雌花的平均比率不超过6％,平均每个榕果内有瘿蚊1～40只不等.瘿蚊寄生不仅降低了垂叶榕的种子数,还致命性地影响着传粉榕小蜂的繁殖.在对瘿蚊的羽化、交配行为及其成虫的活动规律观察中,结果显示:寄生在一个榕果里瘿蚊需要5～7d才能羽化完,其羽化高峰期出现在第2～3天;一天内羽化的高峰出现在上午8:00-10:00及晚上20:00-0:00;而羽化后瘿蚊活动高峰期出现在上午8:00-11:00.雄蚊会帮助雌蚊离开榕果并优先获得交配权,雌蚊交配后飞离繁殖自身的榕树,去寻找适合产卵的榕果繁殖后代,雄蚊不离开羽化树,而死在繁殖自身的榕树附近.这些结果为深入研究瘿蚊的防治技术提供了科学依据.     

Light and suction trap catches of Culicoides midges in southern England

1. The seasonal flight periods are given for eleven species or species groups of Culicoides midges at Pirbright, Surrey, U.K., from 1979 to 1981 and in 1983. 2. Most species were relatively uniformly distributed both within the study site and between years; only C.clintoni Boorman was limited in its spatial distribution and only C.segnis Campbell and Pelham-Clinton varied greatly in numbers between years. 3. Species fall into one of three patterns of seasonal abundance: spring emergers, summer emergers, or spring to autumn emergers. 4. Only the C.obsoletus group showed a pattern of emergence that could correspond to distinct generations, of one or more species in the group. Three distinct emergences were observed, and possible explanations for these discussed. 5. For all species except C.impunctatus Goetghebuer the catches from suction/light and suction only traps are poorly correlated whereas for C.impunctatus they are highly correlated. This may suggest that this species is not greatly attracted to light.