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271.
Cyclotella ortentalis sp. nov, is described from an epilithic sample taken in Lake Imha, located in Kyungsangbuk-do. South Korea. The species is characterized by a conspicuous and short costa regularly extending from each marginal fultoportula to the valve margin. It can be included in the Cyclotella stelligeroid group. The new species can be separated from the most similar species C. stelligera Cleve et Grunov var. stelligera by the more distant position of marginal fultoportulae from the valve margin, the external long tubes of fultoportulae and having short costae. It differs from C. stelligera var. robusta Must, and var. hyalina Hust., in having much denser marginal striae; from C. glomerata H. Bachm., C. pseudostelligera Hust., C. stelligeroides Must, and C. woltereckii Hust., in its much larger valve, coarser marginal striae and short costae with fultoportulae. 相似文献
272.
Abundances of Phlebotomus orientalis, P. papatasi (Diptera: Psychodidae) and other sandflies were investigated in relation to different types of vegetation associated with endemic foci of visceral leishmaniasis (kala-azar) in eastern Sudan. Sandfly collection sites were in Umsalala Village (Galabat Province) and Dinder National Park (Dinder Province). Sandfly species found in the area were P. orientalis, P. papatasi, Sergentomyia africana, S. antennata, S. clydei, S. schwetzi and S. squamipleuris. Among the types of trees in the Dinder area, P. orientalis was more abundant in forests dominated by Acacia seyal than where Combretum kordofanum, Balanites aegyptiaca, Hyphaena thaibaica or Ziziphus spinachristi were the dominant trees. At Umsalala, P. papatasi was more abundant in the village than at any site with dense vegetation, but P. orientalis was uncommon. Sergentomyia spp. were distributed fairly evenly amongst most types of vegetation investigated at both localities. The ecological distribution of sandflies and epidemiology of kala-azar in Sudan are discussed with emphasis on the association of P. orientalis with A. seyal woodlands. 相似文献
273.
Ho Chuan Kun 《Human Evolution》1988,3(5):357-365
New Pliocene hominoid fossils have recently been unearthed from Yuanmou county of central Yunnan province, southwestern China.
This paper will provide free translation of the original chinese publications in which two new species of hominoid, a ramapithecine
and a hominid were described and their associated faunas and stratigraphy. Comments on the taxonomic assignment of these fossils
are presented as concluding remarks. 相似文献
274.
L. J. GOUGH H. J. WELCH 《Botanical journal of the Linnean Society. Linnean Society of London》1978,77(3):217-221
The longstanding problem of the true identity of the juvenile conifer clone usually known as Chamaecyparis obtusa 'Sanderi' has been solved by comparing gas chromatograms of solvent extracts of foliage specimens. Forty-seven species of the northern Cupressaceae were compared with 'Sanderi' but close similarity was shown only by juvenile forms of Thuja orientalis. All other species studied showed significant, usually major, differences. 相似文献
275.
The effect of the entomopathogenic fungus Conidiobolus coronatus on the composition of cuticular and internal lipids of Blatta orientalis females
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Monika Paszkiewicz Marek Gołębiowski Joanna Sychowska Mieczysława I. Boguś Emilia Włóka Piotr Stepnowski 《Physiological Entomology》2016,41(2):111-120
The composition of cuticular and internal lipids in females of the cockroach Blatta orientalis L. exposed to the entomopathogenic fungus Conidiobolus coronatus is investigated. The compositions of the fatty acids, n‐alkanes, alcohol, sterols and methyl esters in the lipids are chemically characterized. Although contact with virulent colonies of the fungus does not induce insect mortality, significant changes in the lipid profiles, both cuticular and internal, are found. The cuticular extracts of a control group of B. orientalis females contain 24 compounds varying in carbon chain length from C6 to C22. The main cuticular fatty acids identified are: C16:1, C16:0, C18:1 and C18:0. The cuticular lipids of B. orientalis females after exposure to C. coronatus contain only 14 free fatty acids from C8 to C20. The highest concentrations identified are C16:0, C18:2 and C18:1. Analysis by gas chromatography‐mass spectrometry identifies the presence of a homologous series of n‐alkanes containing from 25 to 31 carbon atoms. In the case of the insects after fungal exposure, the content of the n‐alkanes in the cuticular lipid is two‐fold higher compared with the controls. Of the cuticular lipids, 11 alcohols are found, ranging from C12:0 to C20:0. There is no presence of alcohols in the internal lipids of the control B. orientalis females and in all of the extracts from the B. orientalis females after fungal exposure. In the samples analyzed, the most common sterol is cholesterol. This is present in the cuticular lipids and the internal lipids of all of the insects sampled. The cuticular and internal lipids of females contain five fatty acid methyl esters, ranging in size from C15 to C19. 相似文献
276.
Abstract The pollination biology of Heloniopsis orientalis was investigated in the lowlands of south central Japan. The receptive stigma emerges from the perianth before the opening of the perianth, and anther dehiscence is late about two days for perianth opening. The flower therefore is protogynous even though no insects visit the unopen flowers. Receptivity of the stigma is maintained for about 8 days, and even the 10 day-old flower can produce seeds. Self-pollination may be rather common in H. orientalis , which is self-compatible, in particular in the flowers which open on days unfavorable for insect activity. Many species of Diptera and Hymenoptera forage on the flowers, and almost any insect can be their pollinator. Long life, self-compatibility of the flowers, and many kinds of pollinators seem to be factors favoring H. orientalis , which blooms in very early spring when the pollinator supply is unstable but which nevertheless bears many seeds. 相似文献
277.
278.
DANIELLE ROJAS-ROUSSE GERALDINE DOURY CHRISTOPHE TERRASSE ROBERT KALMES 《Physiological Entomology》1995,20(2):147-154
Abstract. The plasticity of the stinging behaviour of female Eupelmidae ( Eupelmus vuilleti Crawford, E. orientalis Crawford Hymenoptera: Eupelmidae) was analysed through the interrelationships of a parasitic community living on larval stage of Callosobruchus maculatus Fabricius (Coleoptera: Bruchidae). In traditional African grainstores, Eupelmus females have at their disposal all the larval stages of their host. Their exploitation is revealed by the sting observed on the host caused by the ovipositor of parasitoid females. This stinging behaviour begins immediately on the adult female's emergence, and thereafter there is a daily increase in the number of hosts stung. Stinging activity is linked to the age of the available hosts, but not all of the hosts available are exploited by the two species studied. This absence of total exploitation could indicate a threshold of activity in the stinging acts which could be in part linked to the secretion activity of the poison glands of parasitoid female.
In females of E. vuilleti and E.orientalis the stinging act is usually associated with egg-laying. The relationship between stinging and egg-laying is stronger in more advanced larval stages of the host.
In the presence of parasitized hosts, females of E. orientalis and E.vuilleti can exhibit hyperparasitism. The majority of larvae (i.e. primary parasitoid) that have been hyperparasitized have been stung and a large number of them are completely inactive. However, E. vuilleti females deposited their eggs in the available space of the pupation chamber of the host. The neonatal larvae from these scattered eggs could exploit any available host without the female having 'prepared the ground' at the time of egg-laying.
In Eupelmidae, all this happens as if there were a complementary action between the females and the neonate which could, if necessary, reinforce and/or compensate for the deficiencies in the host exploitation by the female. 相似文献
In females of E. vuilleti and E.orientalis the stinging act is usually associated with egg-laying. The relationship between stinging and egg-laying is stronger in more advanced larval stages of the host.
In the presence of parasitized hosts, females of E. orientalis and E.vuilleti can exhibit hyperparasitism. The majority of larvae (i.e. primary parasitoid) that have been hyperparasitized have been stung and a large number of them are completely inactive. However, E. vuilleti females deposited their eggs in the available space of the pupation chamber of the host. The neonatal larvae from these scattered eggs could exploit any available host without the female having 'prepared the ground' at the time of egg-laying.
In Eupelmidae, all this happens as if there were a complementary action between the females and the neonate which could, if necessary, reinforce and/or compensate for the deficiencies in the host exploitation by the female. 相似文献