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1.
Moran  J. D. W.  Piasecki  W. 《Hydrobiologia》1994,292(1):171-178
Sphyrion lumpi is a sexually dimorphic, parasitic copepod which causes significant losses in fisheries in the North Atlantic. Studies involving both light and scanning electron microscopy revealed important details of the external morphology of both sexes that are discussed in relation to other members of the family Sphyriidae. Conclusions are drawn regarding the life cycle of S. lumpi. The present finding of this parasite on Urophycis tenuis constitutes a new host record.  相似文献   

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The review contains diagnosis of the genus Oobius Trjapitzin, 1963 (Hymenoptera, Encyrtidae), a key to the females of its 9 species described in the world fauna, and synopsis of the species with data on their distribution and hosts. Special attention is paid to an economically important species, Oobius agrili Zhang et Wang, 2005, introduced from China into USA and Canada for biological control of the emerald ash borer Agrilus planipennis Fairmaire (Coleoptera, Buprestidae), a very dangerous pest of ashes (Fraxinus spp.). This buprestid has also recently penetrated into Russia, which necessitates introduction of its egg parasitoid, O. agrili. Coccidencyrtus pinicola Mercet, 1921 from Spain is transferred to the genus Oobius, hence a new combination, O. pinicola (Mercet), comb. n., is proposed. The lectotype of Tyndarichus rudnevi S. Nowicki, 1928 (type species of the genus Oobius) is designated in the collection of the National Museum of Natural Sciences in Madrid and this is formally fixated in the present review. The material of Oobius has been studied in depositories of St. Petersburg, Warsaw, Madrid, and Monterrey (Mexico).  相似文献   

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Energy dynamics within incipient colonies of the southern African mound dwelling harvester termite Trinervitermes trinervoides (Sj?stedt) (Termitidae: Nasutitermitinae) were investigated. Development of incipient colonies established from field collected alates and changes in energy content of reproductives and brood were studied over a 25 week period in the laboratory. Colonies were then transferred into the field to study the established of the first mound. An initial four-week egg-laying cycle started within a week of pairing. Hatching occurred six weeks later. Two lines emerged from first instar undifferentiated larvae. Small larvae moulted first into minor presoldiers and then minor soldiers. Large larvae developed into major workers. Foraging began once second instar major workers had differentiated 20 weeks after colony foundation. First instar major workers did not forage but there is evidence of pre-foraging utilisation of soil humus. The epigeous mound was produced after three years. The energy available to maintain incipient termite colonies until the first workers start foraging is crucial to their survival. The royal pair of T. trinervoides does not feed during the rearing of the first brood, the fate of which depends largely on the reproductives accumulated energy reserves. The males and females expended 84.54 and 83.07% respectively of their total energy during this period. Once foraging started, the energy content of the royal pair increased and a second egg-laying cycle began. Received 25 July 2007; revised 19 March and 22 May 2008; accepted 4 September 2008.  相似文献   

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Type material of several polychaete species described by Enrique Rioja from Mexican coasts are lost, and the current status of some species is doubtful. Nereis oligohalina (Rioja, 1946) was described from the Gulf of Mexico, but it has been considered a junior synonym of Nereis occidentalis Hartman, 1945, or regarded as a distinct species with an amphiamerican distribution. On the other hand, Nereis garwoodi González-Escalante & Salazar-Vallejo, 2003, described from Chetumal Bay, Caribbean coasts, could be confused with Nereis oligohalina. In order to clarify these uncertainties, Nereis oligohalina is redescribed based on specimens from the Mexican Gulf of Mexico, including a proposed neotype; further, Nereis garwoodi is redescribed including the selection of lectotype and paralectotypes, and Nereis confusa sp. n. is described with material from the Gulf of California. A key for the identification of similar species and some comments about speciation in nereidid polychaetes are also included.  相似文献   

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A new species of Polypedilum (Uresipedilum) Oyewo & Sæther, 1998, Polypedilum (Uresipedilum) minimum sp. n. is described as male. A key to adult males of the subgenus from China is presented.  相似文献   

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The fine structure of the four ocelli ofAnoplodactylus petiolatus was examined using serial longitudinal and transversal sections of the eye hill. Each pigment cup ocellus is composed of a (planconvex) cuticular lens, lens forming hypodermal cells, inverse retinula cells with latticed rhabdom and surrounding tapetum and pigment layers. Within the retinula cells a distal “vitreous” zone, a nucleus zone and a proximal rhabdomeric zone can be distinguished. Retinula cell axons originate proximally. The tapetum cells contain several layers of reflecting crystals. Distally, they have a common microvillous region. The intraretinal “vitreous” zone contains glycogen-like particles in the centre and rough ER in the periphery. Contrary to other Pantopoda vitreous cells, a praeretinal membrane and a vertical lens groove have not been observed inAnoplodactylus. While the presence of four (median) ocelli appears to be a primitive characteristic, the inverse orientation of the retinula cells in combination with a tapetum lucidum represents a highly derived characteristic among arthropod median eyes.  相似文献   

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A new genus of Isotomidae, Bellisotoma gen. n., is described. The new genus is a member of the Proisotoma genus complex and is characterized by a combination of having a bidentate mucro with wide dorsal lamellae that join clearly before the end of mucronal axis without forming a tooth and one strong ventral rib with basal notch that articulates with dens; having abundant chaetotaxy on both faces of dens; and abundant tergal sensilla. Bellisotoma gen. n. shows a furcula adapted to a neustonic mode of life, and may be a Isotopenola-like derivative adapted to neustonic habitats. Subisotoma joycei Soto-Adames & Giordano, 2011 and Ballistura ewingi James, 1933 are transferred to the new genus.  相似文献   

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Sinularia leptoclados (Ehrenberg, 1834) is re-described. Sinularia leptoclados var. gonatodes Kolonko, 1926 is synonymized with Sinularia maxima Verseveldt, 1977. Two new species of Sinularia with digitiform lobules, leptoclados-type surface clubs and unbranched interior spindles, are described. An updated maximum likelihood tree of Sinularia species with leptoclados-type clubs (clade 5C) based on two mitochondrial genes (mtMutS, COI) and a nuclear gene (28S rDNA) is presented.  相似文献   

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Six species of Gastrocopta have been identified from the Pilbara region, Western Australia, by means of comparative analyses of shell and mtDNA variation. Three of these species, Gastrocopta hedleyi, Gastrocopta larapinta and Gastrocopta servilis, have been recorded in the Pilbara for the first time. Gastrocopta sp. CW1 is probably new to science and might be endemic to the region. By contrast, Gastrocopta hedleyi, Gastrocopta larapinta and Gastrocopta mussoni are shown to be widespread.  相似文献   

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A new species of Profundulus, Profundulus kreiseri (Cyprinodontiformes: Profundulidae), is described from the Chamelecón and Ulúa Rivers in the northwestern Honduran highlands. Based on a phylogenetic analysis using cytochrome b and the presence of synapomorphic characters (dark humeral spot, a scaled preorbital region and between 32-34 vertebrae), this new species is placed in the subgenus Profundulus, which also includes Profundulus (Profundulus) oaxacae, Profundulus (Profundulus) punctatus and Profundulus (Profundulus) guatemalensis. Profundulus kreiseri can be distinguished from other members of the subgenus Profundulus by having less than half of its caudal fin densely scaled. Profundulus kreiseri can further be differentiated from Profundulus (Profundulus) oaxacae and Profundulus (Profundulus) punctatus by the absence of rows of dark spots on its flanks. The new species can further be differentiated from Profundulus (Profundulus) guatemalensis by the presence of fewer caudal- and pectoral-fin rays. The new species is distinguished from congeners of the profundulid subgenus Tlaloc (viz., Profundulus (Tlaloc) hildebrandi, Profundulus (Tlaloc) labialis, Profundulus (Tlaloc) candalarius and Profundulus (Tlaloc) portillorum) by having a scaled preorbital region and a dark humeral spot. Profundulus kreiseri and Profundulus portillorum are the only two species of Profundulus that are endemic to the region south of the Motagua River drainage in southern Guatemala and northwestern Honduras.  相似文献   

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Xue X  Fry SC 《Annals of botany》2012,109(5):873-886

Background and Aims

Horsetails (Equisetopsida) diverged from other extant eusporangiate monilophytes in the Upper Palaeozoic. They are the only monilophytes known to contain the hemicellulose mixed-linkage (1 → 3, 1 → 4)-β-d-glucan (MLG), whereas all land plants possess xyloglucan. It has been reported that changes in cell-wall chemistry often accompanied major evolutionary steps. We explored changes in hemicelluloses occurring during Equisetum evolution.

Methods

Hemicellulose from numerous monilophytes was treated with lichenase and xyloglucan endoglucanase. Lichenase digests MLG to di-, tri- and tetrasaccharide repeat-units, resolvable by thin-layer chromatography.

Key Results

Among monilophytes, MLG was confined to horsetails. Our analyses support a basal trichotomy of extant horsetails: MLG was more abundant in subgenus Equisetum than in subgenus Hippochaete, and uniquely the sister group E. bogotense yielded almost solely the tetrasaccharide repeat-unit (G4G4G3G). Other species also gave the disaccharide, whereas the trisaccharide was consistently very scarce. Tetrasaccharide : disaccharide ratios varied interspecifically, but with no consistent difference between subgenera. Xyloglucan was scarce in Psilotum and subgenus Equisetum, but abundant in subgenus Hippochaete and in the eusporangiate ferns Marattia and Angiopteris; leptosporangiate ferns varied widely. All monilophytes shared a core pattern of xyloglucan repeat-units, major XEG products co-chromatographing on thin-layer chromatography with non-fucosylated hepta-, octa- and nonasaccharides and fucose-containing nona- and decasaccharides.

Conclusions

G4G4G3G is the ancestral repeat-unit of horsetail MLG. Horsetail evolution was accompanied by quantitative and qualitative modification of MLG; variation within subgenus Hippochaete suggests that the structure and biosynthesis of MLG is evolutionarily plastic. Xyloglucan quantity correlates negatively with abundance of other hemicelluloses; but qualitatively, all monilophyte xyloglucans conform to a core pattern of repeat-unit sizes.  相似文献   

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Taiga Kasuya 《Mycoscience》2007,48(5):309-311
Aseroë coccinea, an invalid name for a Japanese phalloid, is formally validated. Morphological features of A. coccinea are described and illustrated. This fungus is well distinguishable from the other known species of Aseroë by 7–9 bright red arms dispersed radially on the apex of the receptacle, not bifurcating but simple, and consisting of a single tubulate chamber.  相似文献   

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The corn borer, Ostrinia nubilalis, is a very important pest in different countries, and the in vitro system of the insect could be a useful tool for isolation and characterization of the pathogens and physiological responses of the insect. In this context, a cell line was derived from the hemocytes of the European corn borer and was named AFKM-On-H for, respectively, O. nubilalis, Armand Frappier, King Mongkut Institutes, and Hemocytes. This cell line was initiated and maintained in Ex-Cell 400 medium supplemented with 10% heat-inactivated fetal bovine serum. The cells, mostly spherical in shape, not firmly attached to the plastic culture flasks, were passaged up to 200 times by repeated gentle pipetting of the cells. The doubling times at the 80th and 125th passages at 28°C and at the 122th and 169th passages at 25°C were 40, 29, 35, and 34 h, respectively. The AFKM-On-H cell line was further characterized by the morphology, karyotype, random amplified polymorphic DNA analysis, and isozyme profiles. Susceptibility of the cell line to cytoplasmic polyhedrosis viruses (CPV) Euxoa scandens (EsCPV), Dendrolimus punctatus (DpCPV), and Choristoneura fumiferana (CfCPV); nuclear polyhedrosis viruses [Autographa californica (AcMNPV) wild type and recombinant, Antherea yammamai (AnyaNPV)]; and Chilo iridescent virus was demonstrated. Relative sensitivities of the cell line to Bacillus thuringiensis and Metarhizium anisopliae toxins and effects of the molting hormone 20-hydroxyecdysone on this new hemocyte cell line were characterized.  相似文献   

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