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911.
912.
913.
The Neotropical genus Cecropia is the largest genus of Cecropieae in the Urticaceae family with 61 described species. For many years, the taxonomic study of Cecropia has been based on morphological and anatomical data. However, recent studies have shown that chemical entities present in Cecropia can be used to establish differences between species providing important additional support on its taxonomic classification. The goal of the present study was to contribute to the phytotaxonomic knowledge of this genus to better inform taxonomic decisions. In addition, this is the first time that chemical constituents have been described in the leaves of Cecropia telenitida Cuatrec., a species that until now had not been reported in Central America. We characterized and quantified the polyphenolic composition of the methanol leaf extract of C. telenitida using UPLC-DAD-MS and HPLC-DAD, respectively. Phytochemical analysis showed that this extract was rich in chlorogenic acid and flavone C-glycosides, with isoorientin and isoorientin 2″-O-xyloside as the main compounds. Our data showed a lower chemical diversity and metabolite concentrations than other related species. Morphological, distributional and taxonomic notes, images of the plant and phytochemical comparisons between C. telenitida and selected congeners from Panama are also provided. 相似文献
914.
The work is devoted to a problem of study of the taxonomy phytopathogenic viruses of Far East. The performance to genera, species and strain of viruses identified in Far East region is briefly given. A genus Potyvirus in more detail is described, as the greatest number identified on Far East phytoviruses is included into structure of this genus. In the given article the classification phythopathogenic of Russian Far East is represented, for which basis the classification of viruses of the message of International Committee on the taxonomy of viruses (1995) is taken. 相似文献
915.
Four holotype specimens of Cordyceps parasitic on Elaphomyces that were originally described by Dr. Yosio Kobayasi and Mr. Daisuke Shimizu were relocated, and TNS (National Museum of Nature and Science, Japan) registration numbers (TNS-F-number) were assigned: viz. Cordyceps minazukiensis (TNS-F-197989), C. ophioglossoides var. cuboides (TNS-F-230312), C. valvatistipitata (TNS-F-230284), and Cordyceps × jezoensoides (TNS-F-230286). Two specimens were selected as lectotypes: C. delicatistipitata (TNS-F-230293) and C. ophioglossoides f. alba (TNS-F-18223). Those taxa, except for Cordyceps × jezoensoides, have been treated as members of the genus Elaphocordyceps in the latest taxonomy. The new combination Elaphocordyceps × jezoënsoides (Kobayasi) is proposed. In addition, Elaphomyces asahimontanus Kobayasi, the host of Cordyceps delicatistipitata, is lectotypified (TNS-F-230293). 相似文献
916.
917.
A new orthotrichaceous species, Lewinskya transcaucasica Eckstein, Garilleti & F.Lara, is described, based on several samples collected in the Georgian territories of Greater Caucasus and Lesser Caucasus. The species is best differentiated by its sporophytic characteristics. Its capsules are long ovoid to cup-shaped and smooth and show no differentiation of the longitudinal bands of the exothecial cells. The capsules vary from emerging fully from the perichaetial leaves to having a shortly exserted position. The peristome is double, with an exostome of eight pairs of orange to crimson teeth whose tips are variably cancellated and fenestrated and recurved when dry, and an endostome of eight segments that occasionally alternate with reduced intermediate segments. All of these segments are yellowish to pale orange, mainly linear, uniseriate or partially biseriate, and strongly ornamented on the inner side. The new moss is illustrated and compared with similar taxa around the world. 相似文献
918.
The parasitoid Hymenoptera are one of the most important groups of natural enemies of agriculture and forestry pests and have been used as biological control agents in IPM programs for a long time. The systematic research on parasitoids and their associations with hosts lays a solid base for biological control of pests. Here we summarize the taxonomic studies undertaken on the parasitoid wasps in China in the last eight decades. At present about 48 families in 12 superfamilies of parasitoid Hymenoptera are known in China, of which the majority of the families have been studied to some extent while a number of them are still poorly studied. Around 6000 species of 32 families which dealt with in this paper are known in China, and some of them have been successfully and widely used in the existing biological control while others are potentially useful in future biocontrol program. This overview provides the international audience a general idea about the current state of the systematic study of parasitoid Hymenoptera conducted in China, the known species of parasitoids and the native and introduced species used in biocontrol in China. 相似文献
919.
Of seven species of polychaetous annelids collected from the intertidal zone of Sitakunda coast, Chittagong, Bangladesh, five were new records for the country. The seven are listed, with brief notes on these, some previously recorded! species and others housed in the collections of the Natural History Museum, London. Keys are given to the recorded species of Phyllodocidae, Nereididae, Lumbrineridae, Nephtyidae and Capitellidae of the “Northern Bay of Bengal Ecoregion”, and to the recognised species of Glyceridae from the Bay of Bengal. The worms in this Ecoregion are subject to the outflows of the Irrawaddy, Ganges, Hooghly and Mahanadi Rivers, and many of them are known to be freshwater tolerant. 相似文献
920.
M. WESTERMAN J. M. RITCHIE 《Biological journal of the Linnean Society. Linnean Society of London》1984,21(3):283-298
Extensive collecting of grasshoppers of the genus Phaulacridium in New Zealand has indicated the presence of a new species, P. otagoense Ritchie & Westerman, distributed parapatrically with respect to the common and widespread species, P. marginale (Walker) in the Mackenzie Plains and Central Otago regions of South Island. Phaulacridium otagoense occurs on exposed hillsides with bare patches caused by rabbit grazing while P. marginale is found in adjoining areas with lusher vegetation and less severe erosion. A key to the two species and a differential diagnosis are provided. Statistically significant differences in morphology and in nuclear DNA content and chiasma frequency confirm the separate species status of the two taxa. The present-day distribution and probable allopatric origin of P. otagoense from P. marginale is discussed in the light of past and present vegetational and climatic factors and their recent disruption by human agencies. The holotype and some paratypes of P. otagoense are deposited in the Canterbury Museum, Christchurch, New Zealand and further paratypes are deposited in the Australian National Insect Collection, Canberra and the British Museum (Natural History), London 相似文献