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21.
Rotifers described from the Andes by Murray (1913) and De Beauchamp (1939) as Notholca foliacea (Ehrenberg) are reviewed and re-assessed as Notholca walterkostei De Paggi, 1982. They are compared with N. foliacea and details of the lorica of this species seen with the scanning electron microscope are presented. 相似文献
22.
本文记述了在云南省建水县岔科地区发现的哺乳动物化石。根据豫鼠(Yuomys),定地层时代为晚始新世。这套地层暂称岔科组,以示滇南地区第一个含早第三纪哺乳动物的地点和层位。 相似文献
23.
云南哀牢山南部鸟类的区系分析 总被引:1,自引:0,他引:1
哀牢山南延部分在云南省南部至东南部红河哈尼族彝族自治州(简称红河州)内,呈西北东南走向。南部为热带气候,北部为亚热带气候区。地势起伏虽不若滇西北三大峡谷之剧烈,但河口县与金平县内西隆山峰之高差却约达3,000米。这一南延部分区域内,植被类型复杂,花果繁茂,昆虫种类丰富。如此优越的自然条件,也导致了鸟类种类繁多昌盛的结果。 相似文献
24.
This paper is a revision of genus Crotalaria(Papilionaceae) in Yunnan. 30 species and 2 varieties of this genus have been described so far. Hence, there are 27 species, including 4 exotic species, and 4 varieties are distributed in this very province. Among them, 1 new variety, C. mairei var. pubescens, and 3 new combinations, C. yunnanensis var. heqingensis, C. peguana var. qiubeiensis, and C. albida var. gengmaensis, and 1 new record of China, C. humifusa, are included. In addition, 2 species are combined, they are C. jingpingensis to C. prostrata and C. yuanjiangensis to C. medicaginea. Besides, the pollen morphology in some taxa of this genus has been examined. 相似文献
25.
Ted L. Gragson 《Human ecology: an interdisciplinary journal》1992,20(1):109-130
Information is presented on fishing effort, efficiency, techniques, and catch composition for Pumé men, women, and children along with a conceptual model of fishing as a food procurement strategy. The Pumé are a native lowland South American group living in the topical savanna region of southwestern Venezuela characterized by seasonal flooding. Results are discussed in relation to the Pumé environmental and social situation, and briefly compared with results from other lowland South American groups. 相似文献
26.
SANDRA KNAPP F.L.S. 《Botanical journal of the Linnean Society. Linnean Society of London》1991,106(1):73-89
The Solanum sessile species group is one of eight putatively monophyletic subgroups of the large and diverse Solanum section Geminata. The species group comprises ten species of mostly northern South American trees and shrubs. Characters and character states peculiar to Solanum are discussed in detail. A cladistic analysis of the sessile group yielded four equally parsimonious trees which represent two basic tree topologies. The consensus cladogram is composed of three main clades. Biogeographic analysis using the consensus tree revealed no components in common to the three clades. Possible geographical scenarios are discussed with reference to the geological history of northern South America. 相似文献
27.
文中记述了采自云南盘溪地区一真节甲鱼类化石,根据材料特征认为属于克氏鱼属—新种,即一打得克氏鱼(Clarkeosteus yidadeinsis sp. nov.). 相似文献
28.
本文记述采自云南澜沧江水系的鲤科(鱼丹)亚科鱼类一新属新种。新属裸(鱼丹)属Gymnodanio gen.nov.在侧线、臀鳍条数目等特征上近似于低线(?)属Barilius,但以其除侧线鳞外体裸露无鳞,具不完全之腹棱等而与其及(鱼丹)亚科现有各属相区别。新种命名为条纹裸(鱼丹)G.strigatus sp.nov.。 相似文献
29.
30.
The electrophoretic patterns of the enzyme alcohol dehydrogenase (ADH) from Anastrepha fraterculus and A. obliqua were studied. Two loci were found to code for the enzyme in A. fraterculus, and three in A. obliqua. In both species, all isozymes were active in third-instar larvae. A cationic isozyme (Adh-1) was active mainly in the visceral fat body of both species. In A. fraterculus, the locus had an anionic polymorphic isozyme (Adh-3) that was detected in the parietal fat body. In addition to these two loci, a third locus for an anionic isozyme (Adh-2), which was active in the digestive tube of larvae, was present in A. obliqua and probably resulted from gene duplication. For both species, multiple forms of the isozymes are formed by binding of an NAD-carbonyl compound, as in Drosophila melanogaster. Both larvae and early pupae of A. obliqua had almost twice the specific ADH activity as A. fraterculus. The ethanol content of the host fruit infested with A. obliqua (red mombim) was also higher than that of the host fruit infested with A. fraterculus (guava).This research was supported by grants from Conselho Nacional de Desenvolvimento Científico e Tecnologico (CNPq-PIG 40.2486/82). 相似文献