A sex-specific tri-trophic-level effect in a phoretic association

Hemisarcoptes coccophagus (Acari: Astigmata: Hemisarcoptidae) is an obligate parasite of armored-scale insects (Homoptera: Diaspididae). Hypopodes (non-feeding heteromorphic deutonymphs) of this mite cannot complete their development without a phoretic sojourn on the coccinellid beetle Chilocorus bipustulatus. We tested whether the feeding history of the beetles affects the probability of the hypopodes completing their development. Two diets were offered: armored-scale insects (Homoptera: Diaspididae) (suitable for both beetles and mites) and soft-scale insects (Homoptera: Coccidae) (suitable for the beetles but not for the mites). The hypopodial survival was similar for mites which had been on beetles reared on the different scales. However, female hypopodes which had stayed on beetles reared on soft scales suffered higher mortality than those from Chilocorus reared on armored scales. Male survival was not affected. A tri-trophic-level effect on sex-specific survival in a phoretic association was thus demonstrated.     

A new species of tumbling flower beetles of the genus Mordellaria (Insecta: Coleoptera: Mordellidae) from the Baltic amber

The beetle Mordellaria friedrichi sp. nov. is described from the Baltic amber. The new species differs from extant species of the genus in the shape of the eyes and antennae and in the ratios of the length of the pygidium and length of the elytron, pronotum, and anal sternite.     

Mites (Acari) phoretic on ground beetles (Coleoptera,Carabidae) in a southern taiga forest in the environs of Vologda

Ground beetles were captured in a mixed southern taiga forest near the city of Vologda, Russia, from March to September 2014 using different collection techniques. Of the 250 specimens of ground beetles belonging to 22 species, 109 beetles representing 11 species yielded 326 specimens of mites of the cohorts Gamasina (4 species), Astigmatina (5), and Heterostigmatina (1). Two mite species, Antennoseius pseudospinosus Eidelberg, 1990, a common species in the steppes of southeastern Europe, and Halodarcia incideta Karg, 1969, a polyzonal European hydrophile, are recorded in the taiga zone for the first time. Dorsipes dorsipes Regenfuss, 1968, a specialized parasite of beetles of the genus Carabus Linnaeus, 1758, is new to the fauna of Eastern Europe. An adult mite of the genus Stylochirus G. Canestrini et R. Canestrini, 1882 was found for the first time in a natural hibernating chamber in close contact with an overwintering ground beetle, in particular, a male of S. fimetarius (Müller, 1859) on Carabus granulatus Linnaeus, 1785. The most common mite to occur on ground beetles was Antennoseius bullitus Karg, 1969, which was found on 7 carabid species with the mean occurrence of 41% and comprised 68% of the total mite sample. Joint phoresy of 2–3 mite species was recorded on 12 specimens of ground beetles; in 5 cases the co-occurring mites were Antennoseius bullitus and Stylochirus fimetarius. Three dominant mite species (85% of the total mite sample) were mainly collected off three dominant carabid species (70% of the beetle sample), but individual mite species preferred different hosts.     

Molecular and biochemical properties of storage mites (except Blomia species)

In recent years, the allergological importance of different mite species not belonging to the family Pyroglyphidae has been demonstrated. These mites, commonly named storage mites, include Lepidoglyphus destructor, Glycyphagus domesticus, Tyrophagus putrescentiae, Acarus siro, Aleuroglyphus ovatus, Suidasia medanensis and Thyreophagus entomophagus. Several allergens from these species have been purified, sequenced and cloned. Many of these allergens have shown sequence homology and a biological function similar to those previously described in Blomia tropicalis and the Dermatophagoides spp. The main allergens described in storage mites include fatty acid binding proteins, tropomysin and paramyosin homologues, apoliphorine like proteins, alfa-tubulines and other, such as group 2, 5 and 7 allergens, which definitive biological function has not been described yet. Besides the purification and characterization of allergens, the allergenicity of other species such as Acarus farris, Austroglycyphagus malaysiensis, Blomia kulagini and B. tjibodas, Cheyletus eruditus, Chortoglyphus arcuatus, Gohieria fusca, Thyreophagus entomophagus and Tyrophagus longior has been investigated. Research has also been conducted to identify allergens in parasitic mites, such as Psoroptes ovis, Sarcoptes scabiei, Varroa jacobsoni, Diplaegidia columbae and Hemisarcoptes cooremani. The allergenicity of mites present in agricultural environments has been investigated. Crossreactivity studies have also been performed to elucidate to what extent all these mites share common, or species specific epitopes. Herein we present a comprehensive review of the allergenicity of mite species which have been implicated in human respiratory and/or dermatological diseases.     

Attachment site and infestation parameters of parasitic water mites on the whirligig beetle Dineutus nigrior Roberts (Coleoptera: Gyrinidae)

Larval water mites parasitise a wide range of aquatic insects and may have a negative impact on host fitness. One host taxon susceptible to water mite parasitism is the whirligig beetle (Coleoptera: Gyrinidae). We made 11 collections of the whirligig beetle Dineutus nigrior Roberts from May to October of 2006 to investigate patterns of water mite parasitism on that host species. Mites were identified as of the genus Eylais. Mite intensity ranged from 1 to 11. Median intensity was 1.0 and ranged from 1.0 to 3.0 for individual samples. There did not appear to be temporal patterns in mite intensity. Prevalence was 30.9% but varied substantially over the sampling period ranging from 2.5 to 63.3%. Mites were attached to the metathoracic wings and the body tergites under the elytra. When all samples were considered there was equal use of wings and body tergites but there was temporal variation in the use of attachment sites.     

中国云南小兽体表革螨的群落相似性

运用系统聚类分析方法对中国云南省境内17种主要小型哺乳动物(小兽)体表革螨群落相似性进行研究,每一种小兽体表的所有外寄生革螨被定义为一个相应的革螨群落。运用SPSS11.5软件完成17种革螨群落的相似性比较。研究结果表明:小兽体表革螨群落结构复杂,物种多样性高;隶属同一个属的小兽体表的革螨群落相似程度高,在系统聚类分析中聚为一类;大多数革螨群落相似性大小与相应小兽宿主在动物分类上的近缘性高低呈现高度一致,但也有一些革螨群落是例外的。这说明小兽体表革螨群落不仅受小兽宿主分类地位的影响,可能还受宿主生境的影响     

A NEW SPECIES OF THE GENUS MICROPELUS (COLEOPTERA: STAPHYLINIDAE: MICROPEPLINM) IN CHINA

Abstract  This paper describes a new species, Micropeplus dentatus , sp. nov., of the rove beetle subfamily Micropeplinae (Coleoptera: Staphylinidae) from Zhejiang Province, China. The new species belongs to tesserula group of the genus Micropeplus and is characterized mainly by two discal costae on elytron and no punctures on dorsal surface, strong carina on vertex, strong pseudepipleura and its special genitalia. It is similar to Micropeplus sharpi Sawada from Japan. The type specimens are deposited at the Institute of Zoology, the Chinese Academy of Sciences.     

中国铠甲属Micropeplus一新种(鞘翅目:隐翅虫科:铠甲亚科)(英文)

记述铠甲属一新种,微齿铠甲Micropeplus dentatus,sp.nov.,新种采自浙江省镇姚。新种鞘翅具两条盘脊,体表无刻点,但具革质刻纹,属于tesserula group。这是该类群在我国的第一次纪录。新种与日本种Micropeplus sharpi Sawada极为相似,新种中足胫节内缘具11个小齿与日本种的8个小齿明显不同。新种主要鉴别特征为:头顶中脊发达,鞘翅具伪缘折脊,中足胫节内缘具11个小齿。模式标本保藏在中国科学院动物研究所标本馆内。     

Strong indirect interactions of Tarsonemus mites (Acarina: Tarsonemidae) and Dendroctonus frontalis (Coleoptera: Scolytidae)

Phoretic mites of bark beetles are classic examples of commensal ectosymbionts. However, many such mites appear to have mutualisms with fungi that could themselves interact with beetles. We tested for indirect effects of phoretic mites on Dendroctonus frontalis, which attacks and kills pine trees in North America. Tarsonemus mites are known to carry ascospores of Ophiostoma minus, which tends to outcompete the mutualistic fungi carried by D. frontalis. Experimental additions and removals of mites from beetles demonstrated that Tarsonemus propagate O. minus in beetle oviposition galleries. Furthermore, the abundance of Tarsonemus and O. minus tended to covary in nature. These results verified a strong mutualism between Tarsonemus and O. minus. Results also indicated that O. minus is an antagonist of D. frontalis: beetle larvae seldom survived in the presence of O. minus (compared to 83% survival elsewhere). Apparently, this is an indirect result of O. minus outcompeting the two species of mycangial fungi that are critical to beetle nutrition. Thus, Tarsonemus mites close a loop of species interactions that includes a commensalism (mites and beetles), a mutualism (mites and O. minus), asymmetric competition (O. minus and mycangial fungi), and another mutualism (mycangial fungi and beetles). This interaction system produces negative feedback that could contribute to the endogenous population dynamics of D. frontalis. Reproductive rate of Tarsonemus was more temperature‐sensitive than beetle generation time (which constrains the time for mite reproduction within a tree). This differential temperature sensitivity produces a narrow range of temperatures (centred at 27°C) in which mite reproduction per D. frontalis generation can attain its maximum of 100 mites/beetle. Consequently, seasonal oscillations in temperature are predicted to produce oscillations in the D. frontalis community, and climatic differences between regions could influence the community to dampen or exacerbate the cyclical outbreak dynamics of D. frontalis.     

Mites are the most common vectors of the fungus Gondwanamyces proteae in Protea infructescences

Entomochoric spore dispersal is well-documented for most ophiostomatoid fungal genera, most of which are associated with bark or ambrosia beetles. Gondwanamyces spp. are unusual members of this group that were first discovered in the flower heads of the primitive angiosperm genus Protea, that is mostly restricted to the Cape Floristic region of Africa. In this study, we present the discovery of the vectors of Gondwanamyces proteae in Protea repens infructescences, which were identified using PCR, direct isolation, and light microscopy. Gondwanamyces proteae DNA and ascospores were identified on diverse lineages of arthropods including beetles (Euderes lineicolis and Genuchus hottentottus), bugs (Oxycarenus maculates), a psocopteran species and five mite (Acari) species. Based on isolation frequency, however, a mite species in the genus Trichouropoda appears to be the most common vector of G. proteae. Gondwanamyces spores were frequently observed within pit mycangia at the base of the legs of these mites. Manipulative experiments demonstrated the ability of mites to carry viable G. proteae spores whilst in transit on the beetle G. hottentottus and that these mites are able to transfer G. proteae spores to uncolonised substrates in vitro. Interestingly, this same mite species has also been implicated as vector of Ophiostoma spores on P. repens and belongs to the same genus of mites that vector Ophiostoma spp. associated with pine-infesting bark beetles in the Northern Hemisphere.     

Defensive spines are associated with large geographic range but not diversification in spiny ants (Hymenoptera: Formicidae: Polyrhachis)

Several prominent evolutionary theories propose mechanisms whereby the evolution of a defensive trait or suite of traits causes significant shifts in species diversification rate and niche evolution. We investigate the role of cuticular spines, a highly variable morphological defensive trait in the hyperdiverse ant genus Polyrhachis, on species diversification and geographic range size. Informed by key innovation theory and the escape-and-radiate hypothesis, we predicted that clades with longer spines would exhibit elevated rates of diversification and larger range sizes compared to clades with shorter spines. To address these predictions, we estimated phylogenetic relationships with a phylogenomic approach utilizing ultraconserved elements and compiled morphological and biogeographic trait databases. In contrast to the first prediction, we found no association between diversification rate and any trait (spine length, body size and range size), with the sole exception of a positive association between range size and diversification in one of three trait-based diversification analyses. However, we recovered a positive phylogenetic correlation between spine length and geographic range size, suggesting that spines promote expanded geographic range. Notably, these results were consistent across analyses using different phylogenetic inference approaches and spine trait measurement schemes. This study provides a rare investigation of the role of a defensive trait on geographic range size, and ultimately supports the hypothesis that defensive spines are a factor in increased range size in Polyrhachis ants. Furthermore, the lack of support for an association between spines and diversification, which contrasts with previous work demonstrating a positive association between spines and diversification rate, is intriguing and warrants further study.     

Phoretic Poecilochirus mites specialize on their burying beetle hosts

Recurring species interactions can cause species to adapt to each other. Specialization will increase the fitness of symbionts in the coevolved association but may reduce the flexibility of symbiont choice as it will often decrease fitness in interactions with other than the main symbiont species. We analyzed the fitness interactions between a complex of two cryptic mite species and their sympatric burying beetle hosts in a European population. Poecilochirus mites (Mesostigmata, Parasitidae) are phoretic on burying beetles and reproduce alongside beetles, while these care for their offspring at vertebrate carcasses. While Poecilochirus carabi is typically found on Nicrophorus vespilloides beetles, P. necrophori is associated with N. vespillo. It has long been known that the mites discriminate between the two beetle species, but the fitness consequences of this choice remained unknown. We experimentally associated both mite species with both beetle species and found that mite fitness suffered when mites reproduced alongside a nonpreferred host. In turn, there is evidence that one of the beetle species is better able to cope with the mite species they are typically associated with. The overall fitness effect of mites on beetles was negative in our laboratory experiments. The Poecilochirus mites studied here are thus specialized competitors or parasites of burying beetles.     

The elytra-to-body binding mechanism of the flightless rainforest species Tabarus montanus Kaszab (Coleoptera: Tenebrionidea)

The elytra-to-body binding mechanism of the flightless rainforest species Tabarus montanus Kaszab (Coleoptera: Tenebrionidea) is described. Previously, studies on this complex character system in tenebrionids have focused mostly on either fully-winged or flightless, desert-dwelling species with a hermetically sealed subelytral cavity. Data presented here show that the rainforest species Ta. montanus has permanently joined interlocking macrostructures between the two elytra along the midline and between the elytral epipleuron and the sides of the body. These are very similar adaptations to ones found in flightless desert tenebrionids. Frictional patches of microtrichia, previously reported in all wing-folding beetle suborders including flightless taxa, are completely absent in Ta. montanus. This constitutes the first report of the complete loss of frictional microtrichia patches in a beetle with fully-developed elytra. Sensory organs (hair sensilla), usually involved in the correct positioning of the elytra over the beetles’ body at rest are also absent in Ta. montanus. The significance of these results relating to the evolution of the tenebrionid subelytral cavity is discussed.     

Population dynamics ofHemisarcoptes coccophagus Meyer (Astigmata: Hemisarcoptidae) attacking three species of armored scale insects (Homoptera: Diaspididae)

The parasitic miteHemisarcoptes coccophagus Meyer (Astigmata: Hemisarcoptidae) feeds on armored scale insects (Homoptera: Diaspididae). Three host scales were studied: chaff scale (Parlatoria pergandii Comstock andP. cinerea Hadden) infesting citrus (grapefruit and orange) orchards, latania scale [Hemiberlesia lataniae (Signoret)] and olcander scale (Aspidiotus nerii Bouche) occurring on acacia (Acacia cyanophylla) branches and leaves. The overall dynamics of mite populations were similar on the different scale species, although the level of attack on each sampled diaspidid host was different. Rates of young mite stages were highly variable on all three hosts throughout the sampling period while adult rates were stable, constituting around 20% of all mites. No oviposition by mites occurred in mid-winter on any scale species, on any plants or parts, at all sampling sites. Of the three diaspidids, highest mite prevalence (parasitization rate) occurred on latania scale. Mite prevalence on oleander scale infesting mature leaves was higher than on young leaves.H. coccophagus apparently first attacks latania scale on branches, it then disperses to the same host inhabiting mature leaves, from there to co-occurring oleander scale and finally to oleander scale infesting young leaves. Mite prevalence on chaff scale was influenced by host plants and climatic regions: in the Negev it was higher than in the coastal plain, with scales on grapefruit being more heavily attacked at the former site but not on coastal plain. Our data suggest thatH. coccophagus prefers ovipositing scale females. The decreasing order of preference for other scale stages was: young females immature males, 2nd-instar nymphs females.     

Patterns of infestation by the trombiculid mite Eutrombicula alfreddugesi in four sympatric lizard species (genus Tropidurus) in northeastern Brazil

We studied the parasitism by the chigger mite Eutrombicula alfreddugesi on four sympatric lizard species of the genus Tropidurus in Morro do Chapéu, Bahia state, Brazil: T. hispidus, T. cocorobensis, T. semitaeniatus and T. erythrocephalus. For each species, we investigated the patterns of infestation and analyzed to which extent they varied among the hosts. We calculated the spatial niche breadth of the chigger mite on the body of each host species and the distribution of mites along the hosts' bodies for each Tropidurus species. All four species of Tropidurus at Morro do Chapéu were parasited by the chigger mite, with high (97-100%) prevalences. Host body size significantly explained the intensity of mite infestation for all species, except T. erythrocephalus. The body regions with highest intensity of infestation in the four lizard species were the mite pockets. The spacial niche width of the chigger varied consistently among the four lizards species studied being highest for T. erytrocephalus and lowest for T. cocorobensis. We conclude that the distribution and intensity with which lizards of the genus Tropidurus are infested by Eutrombicula alfreddugesi larvae results from the interaction between aspects of host morphology (such as body size and the occurrence and distribution of mite pockets) and ecology (especially microhabitat use).     

Geographical variation in the species Montivagum dihumerale and speciation in chigger mites (Acari: Trombiculidae)

Intraspecific morphological variation of the chigger mite species Montivagum dihumerale (Traub et Nadchatram, 1967) is studied. Eco-geographic rules of the variation are revealed. General size of mites is found to be increased along with the rise of the high-mountain character of the landscape in the collection localities. The numbers of idiosomal setae are varied independently from the size parameters and geographically close populations are proved to be the most similar by these characters. At the same time, numbers of the setae of different types play the leading role in the discrimination of closely related Montivagum species, while the eco-geographical rules have not been found in this genus at the level of interspecific differences. As a result, the hypothesis is set up, that a significant degree of isolation of local populations separated from each other by high mountain ranges of the Central Asia is the main factor of speciation in the genus Montivagum. Regional character of this speciation mode is confirmed by the comparison with other chigger mites taxa.     

Intraspecific variation in morphology of spiny pollen grains along an altitudinal gradient in an insect-pollinated shrub

• Intraspecific variations in pollen morphological traits are poorly studied. Interspecific variations are often associated with pollination systems and pollinator types. Altitudinal environmental changes, which can influence local pollinator assemblages, provide opportunities to explore differentiation in pollen traits of a single species over short distances. The aim of this study is to examine intraspecific variations in pollen traits of an insect-pollinated shrub, Weigela hortensis (Caprifoliaceae), along an altitudinal gradient.
• Pollen spine phenotypes (length, number and density), pollen diameter, lipid mass (pollenkitt) around pollen grains, pollen production per flower and pollinator assemblages were compared at four sites at different altitudes.
• Spine length and the spine length/diameter ratio of pollen grains were greater at higher altitudes but not correlated with flower or plant size. Spine number and density increased as flower size increased, and pollen lipid mass decreased as plant size increased. Bees were the predominant pollinators at low-altitude sites whereas flies, specifically Oligoneura spp. (Acroceridae), increased in relative abundance with increasing altitude.
• The results of this study suggest that the increase in spine length with altitude was the result of selection favouring longer spines at higher-altitude sites and/or shorter spines at lower-altitude sites. The altitudinal variation in selection pressure on spine length could reflect changes in local pollinator assemblages with altitude.

     

Dynamic associations between <Emphasis Type="Italic">Ips sexdentatus</Emphasis> (Coleoptera: Scolytinae) and its phoretic mites in a <Emphasis Type="Italic">Pinus pinaster</Emphasis> forest in northwest Spain

The relationship between the pine bark beetle Ips sexdentatus and its phoretic mites in a Pinus pinaster forest in northwest Spain was studied during 2014. Four species of mites were collected, three of them from the body of the beetle—Histiostoma ovalis, Dendrolaelaps quadrisetus and Trichouropoda polytricha—the fourth, Cercoleipus coelonotus, was collected from the sediments. The main aims of this study were to explore (1) mite diversity and related parameters, (2) the location on the body of the (male and female) beetle, as well as mite assemblages, and (3) the seasonal dynamic association between mite species and the beetle. Results indicated that the diversity oscillated around 0.71 through the study period and the most dominant, frequent and abundant mite was H. ovalis. Histiostoma ovalis was found attached to almost all parts of the body (mainly on the elytral declivity and ventral thorax), whereas D. quadrisetus was exclusively found under the elytra, and T. polytricha displayed affinity towards the elytral declivity as well as the ventral thorax. None of the mite species displayed any preference for the sex of the beetle and the most frequent mite assemblage was H. ovalis, T. polytricha and D. quadrisetus all together. Maximum abundance of each phoretic mite species was related with each of the flight peaks of the beetle that would indicate that these mite species use phoresy as a primary method of transport for colonizing new food sources.     

Bark and ambrosia beetles (Curculionidae: Scolytinae), their phoretic mites (Acari) and associated Geosmithia species (Ascomycota: Hypocreales) from Virgilia trees in South Africa

Bark and ambrosia beetles are ecologically and economically important phloeophagous insects that often have complex symbiotic relationships with fungi and mites. These systems are greatly understudied in Africa. In the present study we identified bark and ambrosia beetles, their phoretic mites and their main fungal associates from native Virgilia trees in the Cape Floristic Region (CFR) of South Africa. In addition, we tested the ability of mites to feed on the associated fungi. Four species of scolytine beetles were collected from various Virgilia hosts and from across the CFR. All were consistently associated with various Geosmithia species, fungi known from phloeophagous beetles in many parts of the world, but not yet reported as Scolytinae associates in South Africa. Four beetle species, a single mite species and five Geosmithia species were recovered. The beetles, Hapalogenius fuscipennis, Cryphalini sp. 1, and Scolytoplatypus fasciatus were associated with a single species of Elattoma phoretic mite that commonly carried spores of Geosmithia species. Liparthrum sp. 1 did not carry phoretic mites. Similar to European studies, Geosmithia associates of beetles from Virgilia were constant over extended geographic ranges, and species that share the same host plant individual had similar Geosmithia communities. Phoretic mites were unable to feed on their Geosmithia associates, but were observed to feed on bark beetle larvae within tunnels. This study forms the first African-centred base for ongoing global studies on the associations between arthropods and Geosmithia species. It strengthens hypotheses that the association between Scolytinae beetles and dry-spored Geosmithia species may be more ubiquitous than commonly recognised.     

二双斑唇瓢虫对矢尖蚧的捕食作用

研究了二双斑唇瓢虫（Chilocorus bijugus Mulsant)对矢尖蚧（Unaspis yanonensis Kuwana)的捕食作用,结果表明,瓢虫雌成虫对矢尖蚧各虫态的功能反应呈Holling II型,瓢虫对矢尖蚧的捕食效应随捕食者个体间干扰作用的增加而下降,捕食作用率（E）随着瓢虫数增加呈幂函数下降曲线,温度对瓢虫的捕食效应具有显著的影响,寻找效率（a)和处置时间（Th)与温度之间呈二次函数关系,猎物密度对瓢虫生殖力的影响呈Logistic曲线。