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排序方式: 共有73条查询结果,搜索用时 31 毫秒
1.
Systemic Practice and Action Research - This paper discusses work in progress with an Indigenous housing association in Central Australia. It builds on and extends a 2-year policy and planning...  相似文献   
2.
《Journal of Natural History》2012,46(8):1253-1259
The life history and hitherto unknown males of Calamiscus cryptopalpis are described. A second species of this genus, C. inflativenis n. sp. is described from Costa Rica. The species C. cryptopalpis is a gregarious parasitoid of injured stingless bees in Costa Rica. The co-occurrence of a specimen of the genus Calamiscus in a piece of amber with the oldest known fossil bee is hypothesized to be the most ancient host-parasitoid relationship between a pair of insect species documented thus far. The otherwise rarely-seen fly was probably lured to the amber site by the alarm pheromones of the bee, and then trapped in the sticky tree resins.  相似文献   
3.
A new species of bathypelagic planktonic ostracod is described and a comparative study made between it and the closely-related species Conchoecia dasyophthalma Müller, 1906. The new species occurs deeper in the water column than C. dasyophthalma, it is smaller and can easily be recognized by its size and the unusual position of the right asymmetrical gland.  相似文献   
4.
Ptilinus fuscus (Anobiidae) was confirmed as the host species of Pelecotoma fennica (Rhipiphoridae, Pelecotominae). Females of Pelecotoma oviposit into the wood infested by the host larvae. First-instar larvae are elongate, unsclerotized, very different from the triungulinid larvae known in other rhipiphorids. They search actively for the host larvae in the wood; no phoresy is involved in the life cycle. The first-instar larvae temporarily paralyse the host larva and enter its body, overwintering (some perhaps more than once) as an endoparasite. In the spring of the year of emergence, the endoparasite engorges enormously (without moulting) and develops a special sclerotized caudal structure which is then used for perforation of the host's integument. The larva undergoes a further four ectoparasitic instars. The fifth (i.e. fourth ectoparasitic) instar differs considerably from the preceding three, and is capable of boring through the wood to prepare the emergence gallery for the adult. Pupation occurs in the wood. The rate of parasitization may locally far exceed 50%. Superparasitization by the first-instar larvae is possible, but usually only 1 larva survives to the ectoparasitic stage. Larval morphology of Pelecotoma is described and illustrated. Additional data on bionomics and larval morphology are also presented for the genus Metoecus (Rhipiphorinae). Comparing the biology and larval morphology of Pelecotoma with other Rhipiphoridae, it is assumed that ancestral rhipiphorids may have been xylophilous Tenebrionoidea with predaceous or omnivorous larvae, and that the ‘triungulinid’ larvae and phoretic habits may not belong to the groundplan of the family Rhipiphoridae. The widespread opinion considering Rhipiphoridae closely related to the family Mordellidae is questioned.  相似文献   
5.
A long-term survey of tritrophic (plant–aphid–parasitoid) associations in the urban ecosystems of Lleida (Catalonia) and Paris (France) resulted in the detection of associations of two bamboo aphids, Takecallis arundinariae (Essig) and Takecallis taiwanus (Takahashi), respectively, with a new aphid parasitoid species. Trioxys remaudierei Starý & Rakhshani sp. nov. is described and illustrated as a unique parasitoid of Takecallis aphids outside the area of their origin. The new species is easily distinguishable from its congeners in having the ventral prongs of the abdomen fused over two-thirds of their length, then bifurcated towards the tip. The only morphologically similar species is Trioxys betulae (Marshall), which exhibits a clearly different prong shape (and has a different host range, Symydobius Mordvilko and Clethrobius Mordvilko). The new species is compared with allied taxa associated with bamboo aphids. The occurrence of Takecallis taiwanus on bamboo is recorded in France for the first time.

www.zoobank.org/urn:lsid:zoobank.org:pub:ED15BA16-E8A9-4CEA-BDA7-FBAB02FEB091  相似文献   

6.
《Journal of Natural History》2012,46(27):2559-2578
The ichneumonid wasp genera Skiapus Morley, Hellwigia Gravenhorst, Nonnus Cresson, Chriodes Förster, and Klutiana Betrem are each formally removed from the Campopleginae on the basis of morphological, molecular, and simultaneous analyses using PAUP* and the optimization alignment program POY. Skiapus and Hellwigia are shown to form a monophyletic group with the Ophioninae to which they are transferred. Nonnus is treated as comprising the Nonninae stat. nov. and Chriodes and Klutiana (sometimes treated as a junior synonym of Chriodes) are treated as comprising the Nesomesochorinae stat. rev. The status of Nesomesochorinae and Nonninae is not fully resolved as they are not consistently recovered as separate groups, forming a single clade in some analyses. We keep them separate because of this uncertainty. Molecular synapomorphies within the D2–3 expansion region of the 28S rDNA gene show the utility of this gene region in determining subfamily‐level placement within the higher Ophioniformes.  相似文献   
7.
《Journal of Natural History》2012,46(39-40):2605-2607
ABSTRACT

The purpose of this paper is to describe the circumstances of publication of an unavailable name of chalcid wasps, and to make the name Balcha opaca Fusu sp. n. (Hymenoptera: Eupelmidae) available.

www.zoobank.org/urn:lsid:zoobank.org:pub:38F49D79-F5AA-4516-8E48-55CFFA61A71C  相似文献   
8.
《Journal of Natural History》2012,46(33-36):2267-2282
The presence of the ovipositor clip is surveyed throughout Figitidae. This morphological structure is postulated to restrain the parasitoid host during oviposition. All Figitinae and Eucoilinae that attack semi‐concealed dipterous hosts were found to possess the clip. Figitids that attack fully concealed hosts all lacked the ovipositor clip. It is hypothesized here that two subfamilies, the Anacharitinae and Aspicerinae, attack fully exposed hosts yet lack the clip in order to quickly oviposit and prevent fighting with the host. Mapping of the presence/absence of the ovipositor clip on to two competing phylogenies suggests this structure evolved in parallel in Figitinae and Eucoilinae. The evolution of the ovipositor clip is probably responsible for the successful colonization of semi‐concealed dipterous larvae by Eucoilinae.  相似文献   
9.
本文应用稳定同位素技术对贵州喀斯特洞穴青菜洞和癞子洞生态系统的营养级关系进行研究。结果表明,青菜洞和癞子洞食物链的碳源主要为洞穴内土壤有机质,为第一营养级(即初级生产者);洞穴内软体动物的螺类和节肢动物的裸灶螽、马陆等主要以土壤有机质和颗粒有机物为食,为第二营养级(即初级消费者);洞穴内的节肢动物的蜘蛛类和脊椎动物主要以其他动物为食物,为第三营养级(即次级消费者)。本文中青菜洞Δδ15 N的富集因子为2.9‰,癞子洞Δδ15 N的富集因子为2.46‰。  相似文献   
10.
钢管混凝土拱—钢腹板PC箱型系梁组合桥梁   总被引:1,自引:0,他引:1  
为减轻钢管混凝土拱梁组合体系桥的自重,提出了采用钢腹板(平钢腹板或波纹钢腹板)代替PC箱形系梁的混凝土腹板,从而形成钢腹板PC箱形系梁。以一座已建成的钢管混凝土拱梁组合体系桥为原桥,进行了钢腹板PC箱形系梁的试设计研究。结果表明,试设计桥由于减小了自重下的内力,降低了面内自振频率,从而改善了原桥的静力和抗震性能。此外,试设计桥经济性好且方便施工,说明钢管混凝土拱—钢腹板PC箱型系梁组合桥梁是可行的。  相似文献   
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