356 research outputs found

    Les Cerococcus (Asterolecaninae) du Nord Africain

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    1 láminaLe genre Cerococcus créé par Comstock (1882) n'était représenté jusqu'à ces dernières années que par une seule espèce paléarctique, Cerococcus eremobius Scott, décrite des Hauts-plateaux constantinois (Algérie) (H. Scott, 1907).Peer reviewe

    Remarques sur le G. Africonidia McKenzie (Coccoidea-Diaspidinae) avec description d'une espece nouvelle du Cameroun Meridional

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    1 láminaLe g. Africonidia Mc. Kenzie (type : halli Mc. Kenzie) créé -en 1947 pour une espèce originaire de Durban (Afrique du Sud) vivant sur Trichilia sp., est voisin du g. Aonidiella Ben. et Leon., qui comprend de nombreuses espèces africaines. La différence entre ces genres est peu accusée, mais le g. Africonidia Mc. Kenzie, tout en possédent un prosoma dilaté (comme Aonidiella) accuse une ornementation pygidiale se rapprochant davantage du g. Quadraspicliotus Mc. Gil. et Diaspidiotus Leon. tel que le statut en a été définitivement établi.Peer reviewe

    Sur un Hemiberlesia Ckll. nouveau des montagnes du Caméroun (Homoptera: Coccoidea).

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    Nomenklatorische Handlungenmanengoubae Balachowsky, 1953 (Hemiberlesia), spec. n.Nomenclatural Actsmanengoubae Balachowsky, 1953 (Hemiberlesia), spec. n

    Madère

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    A Survey of Scale Insects (Sternorryncha: Coccoidea) Occurring on Table Grapes in South Africa

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    Increasing international trade and tourism have led to an increase in the introduction of exotic pests that pose a considerable economic threat to the agro-ecosystems of importing countries. Scale insects (Sternorryncha: Coccoidea) may be contaminants of export consignments from the South African deciduous fruit industry to the European Union, Israel, United Kingdom and the United States, for example. Infestations of immature scale insects found on South African fruit destined for export have resulted in increasing rates of rejection of such consignments. To identify the risk posed by scale insect species listed as phytosanitary pests on table grapes to the abovementioned importing countries, a field survey was undertaken in 2004–2005 in vineyards throughout all grape-producing regions in South Africa. Coccoidea species found during the current field survey were Planococcus ficus (Signoret), Pseudococcus longispinus (Targioni Tozzetti), Coccus hesperidum L. and Nipaecoccus viridis (Newstead). With the exception of Pl. ficus, which has only been collected from Vitis vinifera (Vitaceae) and Ficus carica (Moraceae) in South Africa, these species are polyphagous and have a wide host range. None of the scale insect species found to occur in vineyards in South Africa pose a phytosanitary risk to countries where fruit are exported except for Ferrisia malvastra (McDaniel) and N. viridis that have not been recorded in the USA. All scale insects previously found in vineyards in South Africa are listed and their phytosanitary status discussed. The results of the survey show that the risk of exporting scale insect pests of phytosanitary importance on table grapes from South Africa is limited

    Pristionchus uniformis, should I stay or should I go? Recent host range expansion in a European nematode

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    Pristionchus pacificus has been developed as a model system in evolutionary developmental biology, evolutionary ecology, and population genetics. This species has a well-known ecological association with scarab beetles. Generally, Pristionchus nematodes have a necromenic association with their beetle hosts. Arrested dauer larvae invade the insect and wait for the host's death to resume development. Only one Pristionchus species is known to frequently associate with a non-scarab beetle. Pristionchus uniformis has been isolated from the chrysomelid Leptinotarsa decemlineata, also known as the Colorado potato beetle, in Europe and North America, but is also found on scarab beetles. This unusual pattern of association with two unrelated groups of beetles on two continents requires the involvement of geographical and host range expansion events. Here, we characterized a collection of 81 P. uniformis isolates from North America and Europe and from both scarab beetles and L. decemlineata. We used population genetic and phylogenetic analyses of the mitochondrial gene nd2 to reconstruct the genetic history of P. uniformis and its beetle association. Olfactory tests on beetles chemical extracts showed that P. uniformis has a unique chemoattractive profile toward its beetle hosts. Our results provide evidence for host range expansion through host-switching events in Europe where P. uniformis was originally associated with scarab beetles and the nematode's subsequent invasion of North America

    Pest categorisation of Dendroctonus micans

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    The Panel on Plant Health performed a pest categorisation of the great spruce bark beetle, Dendroctonus micans (Kugelann), (Coleoptera: Curculionidae, Scolytinae), for the EU. D. micans is a well-defined and distinguishable species, recognised mainly as a pest of spruce (Picea spp.) and pine (Pinus spp.) in Eurasia. Attacks on other conifers (Abies spp., Larix decidua, Pseudotsuga menziesii) are also reported. Supposedly originating from north-eastern Eurasia, D. micans has spread westward and is now distributed throughout the EU (22 Member States). It is a quarantine pest listed in Annex IIB of Council Directive 2000/29/EC for Greece, Ireland and the United Kingdom (Northern Ireland, Isle of Man and Jersey) as protected zones. Wood, wood products, bark and wood packaging material of the conifers genera listed as hosts are considered as the main pathways for the pest, which is also able to disperse several kilometres by flight. The sib-mating habits of the species allow each single female to start a new colony on her own. The pest’s wide current geographic range suggests that it is able to establish anywhere in the EU where its hosts are present. The beetles attack living trees and usually complete their life cycle without killing their host, except under epidemic conditions at the limits of their distribution range, where hundreds of thousands of trees can be killed. Sitka spruce (Picea sitchensis) is particularly susceptible. Biological control using the very specific predatory beetle, Rhizophagus grandis, is a widespread and efficient option that has been implemented in all areas suffering from outbreaks. It is complemented by sanitary thinning or clear-felling. All criteria assessed by EFSA for consideration as potential protected zone quarantine pest were met. The criteria for considering D. micans as a potential regulated non-quarantine pest are not met since plants for planting are not the main pathway

    Bark beetles and pinhole borers (Curculionidae, Scolytinae, Platypodinae) alien to Europe

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    Invasive bark beetles are posing a major threat to forest resources around the world. DAISIE’s web-based and printed databases of invasive species in Europe provide an incomplete and misleading picture of the alien scolytines and platypodines. We present a review of the alien bark beetle fauna of Europe based on primary literature through 2009. We find that there are 18 Scolytinae and one Platypodinae species apparently established in Europe, from 14 different genera. Seventeen species are naturalized. We argue that Trypodendron laeve, commonly considered alien in Europe, is a native species; conversely, we hypothesize that Xyleborus pfeilii, which has always been treated as indigenous, is an alien species from Asia. We also point out the possibility that the Asian larch bark beetle Ips subelongatus is established in European Russia. We show that there has been a marked acceleration in the rate of new introductions to Europe, as is also happening in North America: seven alien species were first recorded in the last decade

    The evolution of mating systems in bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae)

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72492/1/j.1096-3642.1983.tb00858.x.pd

    Insect, Mite, and Nematode Pests of Oat

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