Notes on Scolytus fagi Walsh 1867 with the ignation of a neotype, distribution notes and Key to Scolytus Geoffroy of America east the Mississippi River (Coleoptera, Curculionidae, Scolytinae, Scolytini)

The identification of Scolytus fagi Walsh has been difficult because of the lack of diagnostic literature, the occurrence of several morphologically similar sympatric Scolytus species and the loss of the syntypes. In an effort to reduce taxonomic confusion, we designate a neotype for Scolytus fagi, redescribe the male and female, add new distributional records and create a key for the identification of eastern Scolytus species.     

Scolytus stepheni sp. n. - a new species of bark-beetle (Coleoptera, Curculionidae, Scolytinae) from Northern India with a key to Indian Scolytus Geoffroy, 1762 species

A new species of bark-beetle from Kashmir, Scolytus stephenisp. n., dedicated to the late Professor Emeritus Stephen Lane Wood, is described and figured. Key to Indian Scolytus Geoffroy, 1762 species is provided.     

The Banded Elm Bark Beetle, Scolytus schevyrewi Semenov (Coleoptera, Curculionidae, Scolytinae) in North America: a taxonomic review and modifications to the Wood (1982) key to the species of Scolytus Geoffroy in North and Central America

In 2003, an Asian bark beetle, Scolytus schevyrewi Semenov (Coleoptera: Curculionidae: Scolytinae), the banded elm bark beetle, was detected for the first time in North America. This paper modifies the Wood (1982) key to the species of Scolytus Geoffroy to enable identification of Scolytus schevyrewi in North and Central America. Variation of diagnostic characters in Scolytus schevyrewi is discussed.     

Effect of nutrition of parasites with nectar of melliferous plants on parasitism of the elm bark beetles (Col., Scolytidae)

In the forest of Kljestevica, the elm is attacked by four species of elm bark beetles: Scolytus multistriatus (Marsh.), Scolytus scolytus (Fab.), Scolytus pygmaeus (Fab.) and Scolytus ensifer (Rich.) (Col., Scolytidae). Scolytus multistriatus and S. pygmaeus are the most numerous species. Elm bark beetle is parasitized by four species of parasites: Dendrosoter protuberans (Nees), Ecphylus silesiacus (Ratz.), Coeloides scolyticida (Wesm.) (Hym., Braconidae) and Entedon leucogramma (Ratz.) (Hym., Eulophidae). Ecphylus silesiacus and D. protuberans are the most numerous species. The nectar of mustard ( Sinapis alba L., Brassicaceae) flowers, sweet basil ( Stachys recta L., Lamiaceae) flowers and of wild carrot ( Daucus carota L., Umbelliferae), has an important effect on the number of parasites and on the parasitism of the elm bark beetles. Wild carrot is the most attractive plant to the parasites for additional nutrition, especially for D. protuberans . Mustard and sweet basil flowers are suitable for additional nutrition of E. silesiacus imagos. On meadow flowers growing spontaneously in forest clearings, the lowest number of parasite imagos was collected by an entomological catcher, and the lowest percentage of parasitized larvae and eggs of the elm bark beetle was recorded in elm control catch trunks that were not near the cultivated melliferous plants.     

我国新天敌资源——小蠹蒲螨形态与生物学研究

小蠹蒲螨Pyemotes scolyti(Oudemans,1936)为我国新纪录种。在河北,是核果类果树毁灭性害虫果树小蠹Scolytus japonicus Chapuis和多毛小蠹S.seulensis Mu-rayamy的有效天敌。该螨胎生,1年多代(25℃,8d完成1代),雌雄性比30:1～2,每雌产后代平均60余头,有较高的利用价值。     

A Key to and Annotated List of the Species of the Bark-Beetle Genus Scolytus Geoffroy, 1762 (Coleoptera,Curculionidae: Scolytinae) from European Russia

Entomological Review - A key to and an annotated list of species of the genus Scolytus Geoffroy, 1762 from European Russia are given.     

Ecphylus silesiacus (Ratz.) (Hymenoptera, Braconidae), an important elm bark beetle parasitoid

1 Ecphylus silesiacus (Ratz.) (Hym. Braconidae) parasitizes larvae of elm bark beetles (Coleoptera: Scolytidae) occurring in thin bark. Pteleobius kraatzi (Eichh.), Scolytus pygmaeus (Fab.), Scolytus multistriatus (Marsh) and Scolytus ensifer (Eichh.) are the most suitable hosts. Scolytus scolytus (Fab.) occurring in thicker bark, is not such a suitable host for E. silesiacus. Ecphylus silesiacus only parasitized this species in bark forks. 2 Under experimental conditions, P. kraatzi produced the largest number of elm bark beetle adults per maternal gallery and had the longest development period, while S. scolytus produced the smallest number of adults and had the shortest development period. 3 Ecphylus silesiacus had the lowest reproduction, the shortest development period and the least favourable sexual ratio, on S. scolytus larvae, and the highest production, the longest developmental period and the most favourable sexual ratio on P. kraatzi and S. pygmaeus larvae. 4 Ecphylus silesiacus adults fed with Parker's diet and the nectar of the melliferous plant Daucus carota L. (Umbelliferae), lived longer, parasitized a greater percentage of S. pygmaeus larvae, and had a significant offspring production compared with adults without additional diet.     

Additions to the check list of bark beetles (Coleoptera,Curculionidae: Scolytinae) from Leningrad Province,Russia

The field work of the authors during the last 16 years in both the western and the eastern parts of Leningrad Province, Russia, has resulted in the addition of 7 species to the regional list of bark beetles, namely: Hylurgus ligniperda F., Crypturgus subcribrosus Egg., Pityogenes irkutensis Egg., Scolytus mali Bechst., S. scolytus F., S. pygmaeus F., and Xyleborinus attenuatus Blandf. Of these species, P. irkutensis occurs only in the eastern districts of Leningrad Province, C. subcribrosus, over the whole territory, and the remaining species, only in the western districts. We suggest excluding Polygraphus proximus Blandf. from the regional faunal list. As a result, the updated list of the bark beetle species of Leningrad Province comprises 75 taxa. New data on findings of rare species in the region are considered.     

Phoretic mites and nematode associates of Scolytus multistriatus and Scolytus pygmaeus (Coleoptera: Scolytidae) in Austria

Abstract 1 The species assemblages and abundance of phoretic mites and nematodes associated with the elm bark beetles, Scolytus multistriatus and Scolytus pygmaeus, were studied in Austria. 2 A total of 3922 individual mites were recorded from 144 adults of S. multistriatus and 178 adults of S. pygmaeus. The species spectrum was identical and the relative abundance of mites was very similar for both species of scolytids. Nine mite species, Pyemotes scolyti, Pseudotarsonemoides eccoptogasteri, Trichouropoda bipilis, Tarsonemus crassus, Proctolaelaps eccoptogasteris, Proctolaelaps scolyti, Chelacheles michalskii, nr. Eueremaeus sp. and Elattoma sp. were detected. Two of the nine species, nr. Eueremaeus sp. and Elattoma sp., are documented here as new associates of Scolytus spp. 3 Pyemotes scolyti was the most frequent mite species, and Ps. eccoptogasteri and T. bipilis were relatively common, whereas the other mites occurred occasionally or were rare. 4 The trophic roles of most of the mites associated with S. multistriatus and S. pygmaeus are poorly known, but they may include fungivores, parasitoids of bark beetle broods, predators of bark beetle broods and/or mites and/or nematodes. 5 Besides phoretic mites, two nematode associates were seen on the investigated insects. A species of Cryptaphelenchus occurred under the elytra of both scolytid species, whereas the adults of a Neoparasitylenchus sp. were present inside abdomens of S. multistriatus, but absent from S. pygmaeus.     

Biological control of Dutch elm disease: Bacillus thuringiensis as a potential control agent for Scolytus scolytus and S. multistriatus

J assim , H.K., F oster , H.A. & F airhurst , C.P. 1990. Biological control of Dutch elm disease: Bacillus thuringiensis as a potential control agent for Scolytus scolytus and S. multistriatus. Journal of Applied Bacteriology 69 , 563–568.
The effects of exposing fifth instar larvae of Scolytus scolytus and S. multistriatus to spore suspensions of Bacillus spp. were investigated. Bacillus thuringiensis ser 3a, 3b increased the mortality of larvae cultured on an artificial medium from approximately 20% in control cultures to over 80% in cultures exposed to the bacteria. The mortality was dose-dependent for S. multistriatus and the approximate LC₅₀ value was 2.2 times 10³ spores/ml. Different serotypes of B. thuringiensis caused different levels of mortality: H6 produced the highest mortality and H1 the lowest. Bacillus alvei and B. cereus were also pathogenic but B. megaterium was not. The results are discussed in relation to the mechanism of pathogenicity and the potential for the use of B. thuringiensis for the control of the vectors of Dutch elm disease.     

Phloemophagous and xylophagous insects, their parasitoids, predators and inquilines in the branches of the most important oak species in Serbia

Altogether 26 species of phloemophagous and xylophagous insects, 47 species of parasitoids, 14 species of predators and 7 species of inquilines were identified on the branches of Quercus cerris, Q. frainetto, Q. petraea and Q. robur, diameter 3–15 cm, at 24 sites in Serbia over the period 1992–1996. The greatest number of the identified species were taken from Q. petraea branches (66), followed by Q. cerris (49), Q. frainetto (48) and Q. robur (43). Among the identified phloemophagous and xylophagous insects, the most frequent and the most abundant species were Scolytus intricatus, Agrilus angustulus and Xylotrechus antilope. The most frequent and the most abundant parasitoid was Ecphylus silesiacus. In some samples, the species Entedon ergias, Cheiropachus quadrum and Dendrosoter protuberans were also among the more abundant parasitoids. The most significant predator was the species Tilloidea unifasciata, and the most significant inquilines were the species Poecilothrips albopictus and Asynapta pectoralis.     

Biological control of Dutch elm disease: Larvicidal activity of Trichoderma harzianum, T. polysporum and Scytalidium lignicola in Scolytus scolytus and S. multistriatus reared in artificial culture

A method is described for the culture of larvae of Scolytus multistriatus and Scolytus scolytus on an artificial medium following exposure to cultures of microorganisms. In control cultures, a natural mortality rate of 21.2% was found for S. multistriatus and 17.6% for S. scolytus. The effects of Trichoderma harzianum, T. polysporum and Scytalidium lignicola on fifth instar larvae of S. scolytus and S. multistriatus reared on the artificial medium were studied. The fungi were larvicidal and larval mortality was increased to more than 80% by inoculation of the larvae with the fungi. Another fungus, Phomopsis oblonga, had little effect on larvae of S. scolytus. The results are discussed in relation to mechanism of pathogenicity of the fungi and their potential use in the control of Dutch elm disease. It is proposed that with modifications, the method is applicable to other bark beetle pests.     

The internal microbial flora of the elm bark beetle, Scolytus scolytus, at all stages of its development

Adult Scolytus scolytus emerged from the pupal stage with sterile guts although microorganisms were present within the pupal body. Gut sterility was maintained in a large proportion of newly formed adults while they were boring out of an elm log. The adult gut microbial flora is mainly acquired during subsequent feeding. Differences were found between the microbial gut flora of both larvae and adult S. scolytus, and of both male and female beetles.     

Description of Parasitorhabditis frontali n. sp. (Nemata: Rhabditida) from Dendroctonus frontalis Zimmermann (Coleoptera: Scolytidae)

A new Parasitorhabditis species with males and females was discovered from the southern pine beetle Dendroctonus frontalis and its galleries in loblolly pine, Pinus taeda, growing in Mississippi. Females of the new species have a cupola-shaped tail with a small spike; males possess a 2 + (3+2) + 3 ray pattern on the tail fan with ray 10 reaching the margin, and a distinctive stomatal tooth. Parasitorhabditis frontali n. sp. has some similarities to P. hylurgi Massey, 1974 from Hylurgops pinifex in New York, USA, P. terebranus Massey, 1974 from D. terebrans (Olivier, 1795) in Texas USA, P. ligniperdae Fuchs, 1915 from Hylergops ligniperda (Fabricius, 1787) and P. dendroctoni Rühm, 1956 from D. micans (Kugelann, 1794) in Europe, P. ateri Fuchs, 1915 isolated from the beetle Hylastes ater (Paykull, 1800) in Germany, and P. malii Devdariani and Kakulia,1970 from Scolytus mali (Bechstein, 1805) within the republic of Georgia. Morphometrics for 44 species of Parasitorhabditis are provided to update older keys. Parasitorhabditis frontali n. sp. was initially grown on Malt Extract (ME) agar with its own microbial contaminants that included a bacterium and fungus. The nematode also grew and reproduced after slices of ME agar with nematodes and microbial contaminants were transferred to water agar. It was killed by E. coli on NGM agar plates commonly used to raise other Rhabditida. Drawings of diagnostic anatomy and low-temperature SEM images of bodies, heads, and tails are provided for cultured specimens from pine beetle frass.     

不同颜色粘虫板对多毛小蠹和皱小蠹的诱集效果

试验对比了红、黄、蓝、绿、黑、白六种颜色粘虫板对新疆吐鲁番地区杏树上多毛小蠹(Scolytus seulensis)和皱小蠹(Scolytus rugulosus)的引诱效果,结果表明红色和黑色粘虫板对多毛小蠹的引诱效果明显高于其他颜色;其中黑色粘虫板对皱小蠹的引诱效果最强,平均每块黑板诱捕到(11.8±5.0)头皱小蠹,红色次之,其他颜色对两种小蠹均无明显的引诱效果;红色粘虫板对多毛小蠹的引诱效果最强,平均每块红板诱捕到(16.±3.0)头多毛小蠹,黑色次之,其他颜色对两种小蠹均无明显的引诱效果.通过色板引诱虫量的变化体现出两种小蠹的不同扬飞高峰期,多毛小蠹的扬飞高峰期应在六月初,而皱小蠹的扬飞高峰出现在六月中旬.     

脐腹小蠹形态特征和生物学特性

脐腹小蠹Scolytus schevyrewi Seme.是榆树的一种重要蛀干害虫。本研究在宁夏盐池县通过室内观察和林间调查相结合,研究了脐腹小蠹的形态特征及其生活史、成虫寿命、习性、交尾行为等生物学特性。结果显示:脐腹小蠹虫在宁夏盐池县一年发生2代,以老熟幼虫或蛹越冬,老熟幼虫约占98.2%,蛹约占1.8%。越冬幼虫于5月上旬开始化蛹,5月中旬为化蛹盛期,5月下旬开始羽化,6月上旬为羽化盛期。第2代幼虫于6月底、7月初开始化蛹,7月下旬达羽化盛期,8月上旬羽化结束;脐腹小蠹雌成虫平均寿命为(27.14±3.74)d,雄成虫的平均寿命为(16.86±4.13)d,差异显著(P<0.05);此外,脐腹小蠹无滞育现象;脐腹小蠹的4种天敌,分别是榆小蠹长茧蜂Elachistocontrum sp.、虱形螨Pedieuloids ventricosus Newport、拟截斑郭公虫Thansimus sp.和蠼螋Labidura sp.。     

Rapid-cooling and storage of plant nematodes at -140 degrees C

Low temperatures can assure the long-term or even indefinite preservation of important biological specimens. Nematode cryopreservation allows for the availability of large numbers of living nematodes at any one time, especially for experimental purposes. New isolates of Bursaphelenchus have recently been collected, including Bursaphelenchus eremus (Rühm) Goodey. This species was identified in north-central Italy on dying oak trees and from the bark beetle Scolytus intricatus Ratzeburg as dauer larvae. We therefore, sought to develop a cryopreservation technique for the long-term storage of all available Bursaphelenchus spp. The technique consists of a rapid-cooling protocol involving immersion in a liquid nitrogen bath before storage of the frozen samples in a mechanical freezer at -140 degrees C. The survival of nematodes subjected to this rapid-cooling protocol was higher than previously reported using slow-cooling methods and is suitable for several species of Bursaphelenchus and other phytoparasitic nematodes.     

Three new species of Sesioctonus Viereck (Hymenoptera, Braconidae, Agathidinae) from Peru

Three new species of Sesioctonus (Braconidae: Agathidinae) are described and illustrated, i.e., Sesioctonus huggerti, Sesioctonus wayquecha, and Sesioctonus bina. Two new Peruvian species records for Sesioctonus are reported: Sesioctonus longinoi and Sesioctonus diazi. A revised key to all known species of Sesioctonus is presented.