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1.
Synedra ulna var, repanda Q. X. Wang & Q. M. You, a new variety of Synedra (Bacillariophyta) from Xinjiang, China, is described and illustrated, and the characteristic of the variety: includes undulate-linear valves and straight pseudoraphe, differs from other species of Synedra.  相似文献   

2.
Synedra ulna var. repanda Q. X. Wang & Q. M. You, a new variety of Synedra (Bacillariophyta) from Xinjiang, China, is described and illustrated, and the characteristic of the variety: includes undulate-linear valves and straight pseudoraphe, differs from other species of Synedra.  相似文献   

3.
Two new species of the genus Tinocladia Kylin, T. gracilis sp. nov. and T. microsporangii sp. nov,, are described. T. gracilis is characterized by its slender frond, variable size, infrequently branched medullary filaments, and short assimilating filaments with 2 - 7 cells. T. microsporangii is characterized by its medullary cells which are slightly larger than sub-cortical ones; narrow sub-cortical layer, usually consisting of 4- 6 cells and very small unilocular sporangia. The holotypes are deposited at the Herbarium of the Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.  相似文献   

4.
Middle and Late Cambrian trilobite faunas from the Dama section in western Hunanare are composed of 63 genera and subgenera, 84 species, and two forms ofgen, et sp. indetermined. Which include a mixture of cosmopolitan agnostoids and polymeroids. Three new species,Hardyoides damaensis,Meringaspis damaensis and Rhyssometopu.s (Rodtrifinis) nitidus, are described by present author in 2004. Besides, Erixanium is recognised for the first time in study area, which is significant for biostratigraphical correlation of the Late Cambrian in the Austalo-Asia region. According to distribution regularity vertical, the Middle and Late Cambrian trilobites can be divided into 9 trilobite communities for the Dama section. Based on the trilobite communities analysis, the author concludes that from the east Mt. Lailong to Dama through Fenghuang, further east, reach in Chenxi,the palaeoenvironments were changed from a shallow-water of oxygen-rich (platform margin slope) into a deep-water of oxygen-poor setting (basin).  相似文献   

5.
The living morphology and infraciliature of two rare marine ciliates, Placus salinus Dietz, 1964 and Strombidium apolatum Wilbert and Song, 2005, collected from the coastal waters near Qingdao, China, were investigated by in vivo observation and protargol impregnation technique. The improved diagnosis for Placus salinus is as follows: medium-sized marine Placus, in vivo (50–60)μm×(30–40)μm; cell elliptical to barrel-shaped; 28–31 somatic kineties; single macronucleus usually ellipsoid and one micronucleus located in the indention of the macronucleus; one contractile vacuole posteriorly positioned. Strombidium apolatum is characterized by: marine strombidium (40–60)μm×(30–45)μmm in vivo, cordiform in shape with somewhat pointed posterior end and conspicuous apical protrusion; extrusomes prominent, about 15μm in length and evenly arranged along the circle kinety; about 16 collar and 5–6 buccal membranelles; one elongate macronucleus and one micronucleus; circle and ventral kineties consisting of about 53 and 45 dikinetids respectively.  相似文献   

6.
Sargassum muticum is one of the most abundant and conspicuous native macroalgae species on the northern coasts of China. It often forms large-scale seaweed beds in subtidal zones. This investigation was designed to understand the intraspecific genetic relationships of this alga based on samples collected from four northern coastal sites of China, and to evaluate gamete release and growth capacity in laboratory conditions. The nuclear internal transcribed spacer 2 (ITS2) sequences of 16 samples from four locations were identical. Based on cox3 gene and partial rbcLS operon sequences, intraspecific genetic variability was detected with three and two ribotypes, respectively. Temperature, not irradiance, was shown to significantly affect gamete release and fertilization. Elevated temperature and irradiance enhanced the growth of germlings and vegetative branchlets. Maximum growth rate of germlings was detected at 18-24℃and an irradiance of 60-100 μmol photons/(m^2.s). Under ambient conditions (12-25℃ and 60-125 gmol photons/ (m2.s)), relative growth rate of young branchlets could reach 7.5%/d.  相似文献   

7.
Lower Permian formations within the Buqingshan Mountains (A'nyemaqen ophiolitic zone, eastem sector of the eastern Kunlun) were formed in the following paleogeodynamic environments (from north to south) : ( 1 ) shelf and slope of a passive continental margin in a marginal sea; (2)partially Permian metamorphic rocks of subduction-accretion complexes and volcanogenic rocks of an ensimatic island arc, of the age limited from above by the Asselian - Sakmarian; and (3) an island are slope and oceanic trench. Subduction-accretion complexes and the island are volcanites are overlain with a sharp angular unconformity by a carbonate-conglomerate sequence, which presents as local molasse of the Early Permian age. Based on fusulinids from the basal limestone, the age of the local molasse is first defined as the Yakhtashian-Bolorian, i.e, Artinskian-Kungurian (?). The thorough investigations revealed that the initial closure of the eastern Paleotethys within the eastern Kunlun corresponded to the Sakmarian-Yakhtashian (Artinskian) boundary, whereas in the western Paleotethys sector (Northern Pamirs) the closure occurred considerably earlier, prior to the Late Bashkirian. Thus, the idea that the Paleotethys in the eastern Kunlun reached its maximum width in the Permian, is highly questionable. During the Early Permian the A'nyernaqen branch of the Paleotethys intensely decreased. Beginning from the Bolorian (Kungurian) and up to the end of the Permian this branch represented its relict in the form of a marginal sea depression. It may be suggested that the Paleotethys closure in the A'nyemaqen took place gradually from the west to the east and covered a long period from the Late Carboniferous to the terminal Early Permian.  相似文献   

8.
We describe a new species of gerreid fish,Gerres septemfasciatus,based on four specimens collected from the northern South China Sea.G.septemfasciatus most closely resembles G.limbatus in general appearance.However,G.septemfasciatus is distinguished from the latter and other congeners by having 3 to 3.5 scales between the base of the fifth dorsal spine and lateral line.This species has a distinctive color pattern,including 7-8 regular,vertical,blue-grayish bands on its side.The distribution of this species ...  相似文献   

9.
Two new species of the genusTinocladia Kylin (1940)T. eudesmoides Ding et Lu sp. nov. andTinocladia zhangii Ding et Lu sp. nov., are described.T. eudesmoides is mainly characterized by its longitudinally and transversely produced sub-cortical filaments from the medulla, its short uniseriate assimilating filaments, usually composed of 6–10 cells with slightly swollen and narrow ultimate cells, and its unilocular sporangia (60–115)×55–70μm, variable in size.T. zhangii is mainly characterized by its very solid frond, not rip apart by hands, its evident longer primary branches, its short and slender secondary branches, with very evident sub-cortical layer, and filaments divided repeatedly, and its large and small unilocular sporangia, with the latter borne on an evidently swollen pedicel. Project B80981816 supported by the NSFC. Contribution No. 4443 from the Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.  相似文献   

10.
The authors discribed a new polystigmate combination,Gomphonema turris Ehr. var.okamurae (Skv.) Fan et Bao. comb. nov., and two new varieties,Gomphonema turris Ehr. var.latum Fan et Wang. var. nov. andGomphonema acuminatum var.obtusum Fan et Bao, var. nov., that were distinguished by frustule morphology under LM. The samples were collected from freshwater of Heilongjiang Province, China. Project No. 39899400 supported by the NSFC.  相似文献   

11.
云南洞穴金线鲃属鱼类(鲤科)一新种   总被引:1,自引:0,他引:1  
描记采于罗平县—地下河金线鲃属一新种,命名为瓦状角金线鲃Sinocyclocheilus tileihornesMao,Lu et Li,sp.nov。新种外形与犀角金线鲃S.rhinocerous Li et Tao(1994)相近,但新种无侧线鳞,角顶部分叉呈瓦状,腹鳍较长,后伸超过肛门或达到臀鳍起点可与之相区分。  相似文献   

12.
13.
We describe two new species of Sellaphora from Lake Fuxian, Yunnan Plateau, China. Based on both light and scanning electron microscopy, these species are described as S. yunnanensis sp. nov. and S. sinensis sp. nov. The primary features of S. yunnanensis are: elliptical to linear-elliptical valves with broadly rounded ends, straight filiform raphe, almost straight central endings and small, slightly expanding central pores, small central area, symmetrical or slightly asymmetrical central nodule. The primary features of S. sinensis are: elliptical valves, obtusely rounded ends, similar raphe and axial area, transapically less expanded central area, larger, elliptical central nodule. We compare these species to those of a similar shape and morphology.  相似文献   

14.
描记采于贵州省茂兰自然保护区境内一洞穴的中国野鲮亚科(Labeoninae)一新属长臀鲮属Longanalus,spnov和一个新种大鳍长臀鲮Longanalus macrochiroussp nov。新属以臀鳍分枝鳍条为7根等特征,区别于该亚科所有属;新种以偶鳍发达,胸鳍后伸达到腹鳍基,腹鳍后伸超过臀鳍起点等显著特征命名大鳍长臀鲮。  相似文献   

15.
描记采于贵州省茂兰自然保护区境内一洞穴的中国野鲮亚科(Labeoninae)一新属长臀鲮属Longanalus.sp nov和一个新种大鳍长臀鲮Longanalus macrochirous sp nov。新属以臀鳍分枝鳍条为7根等特征.区别于该亚科所有属;新种以偶鳍发达.胸鳍后伸达到腹鳍基,腹鳍后伸超过臀鳍起点等显著特征命名大鳍长臀鲮。  相似文献   

16.
The Jiayin area along the Heilongjiang River in Northeast China has attracted stratigraphic and sediment-ological interests recently because the Cretaceous-Tertiary (K/T) boundary should be located in this non-marine succession. Dinosaur remains disappear suddenly at the upper part of the Maastrichtian, whereas plants gradually evolved throughout the succession. Analysis of sedimentary facies has been carried out and paleo-environments through Upper Cretaceous to lower Paleocene sections are reconstructed. Fluvial to lacustrine sedimentary environments are inferred from the facies. Several debris flow events have been identified, and it is in these deposits that the dinosaur fossils are concentrated.  相似文献   

17.
The Jiayin area along the Heilongjiang River in Northeast China has attracted stratigraphic and sedimentological interests recently because the Cretaceous--Tertiary (K/T) boundary should be located in this non-marine succession.Dinosaur remains disappear suddenly at the upper part of the Maastrichtian,whereas plants gradually evolved throughout the succession.Analysis of sedimentary facies has been carried out and paleo-environments through Upper Cretaceous to lower Paleocene sections are reconstructed.Fluvial to lacustrine sedimentary environments are inferred from the facies.Several debris flow events have been identified,and it is in these deposits that the dinosaur fossils are concentrated.  相似文献   

18.
描记采于贵州茂兰自然保护区一洞穴的盲副鳅一新种,命名为茂兰盲副鳅Paracobitis maolanensisLi,RanetChen sp nov。该种与产于该县的长须盲副鳅Paracobitis longibarbatusChen,YangetSket(1998)的区别为:①口须纤弱而不是发达;②鼻瓣不成须状;而不是鼻瓣发育成鼻须。③胸鳍较长,后伸接近腹鳍起点且形态特殊;④尾鳍深叉;⑤臀鳍条ii,5;而不是ii,6。新种与分布于广西的后鳍盲副鳅Paracobitis posterodarsalusLi,RaoetChen的区别为:①背鳍起点与腹鳍起点相对;而不是在整个腹鳍之后;②口须纤弱鼻瓣不呈鼻须;而不是口须发达,鼻瓣发育成鼻须;③背鳍条iii,8;而不是iii,6;④臀鳍条ii,5;而不是ii,4;⑤胸鳍长而形态特殊。  相似文献   

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