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1.
Length–weight relationships were determined for seven fish species (Culter oxycephaloides Kreyenberg & Pappenheim, 1908; Pseudobagrus tenuis Günther, 1873; Saurogobio dumerili Bleeker, 1871; Distoechodon tumirostris Peters, 1881; Pseudolaubuca engraulis Nichols, 1925; Liobagrus marginatoides Wu, 1930; and Parabotia bimaculata Chen, 1980) inhabiting the Yuan River, central China. Fishes were collected using gillnets and electroshock fishing techniques quarterly from January 2008 to December 2010. This study is first report the length–weight relationships for this seven fish species.  相似文献   

2.
The length–weight relationships (LWRs) were estimated for ten fish species from the Jingjiang reach of the Yangtze River, China. Samples were collected using a combination set-net consisting of a 40-meter net wall (mesh size: 1.8 cm) and two fyke nets (mesh size: 0.9 cm) on the 1st, 11th and 21st of each month from January 2012 to December 2017. The b values of all species were within the expected ranges, varying between 2.849 and 3.292. This study provides the LWR parameters for Distoechodon tumirostris, Microphysogobio microstomus, Saurogobio dumerili, Squalidus nitens, Acheilognathus gracilis, Sarcocheilichthys kiangsiensis, Sarcocheilichthys parvus, Rhodeus fangi, Micropercops swinhonis, Repomucenus olidus.  相似文献   

3.
4.
Hou CL  Piepenbring M 《Mycopathologia》2005,159(2):299-306
Three species of Rhytisma are described based on recently collected specimens from the Anhui province, China. Rhytisma anhuiense is a new species causing a serious tar spot disease on Rhododendron simsii. Rhytisma yuexiense is a new species, which develops its stromata only on fallen leaves of Rhododendron ovatum. Rhytisma himalense on Ilex fargesii is a known species and probably widely distributed in China. Including the two new species, 11 species of Rhytisma are known from China which are presented in a key.  相似文献   

5.
鲂属鱼类的分类整理   总被引:21,自引:4,他引:21  
鲂属(Megalobrama)隶属于鲤科(Cyprinidae)的鲌亚科(Cultrinae),是一群较大型的经济鱼类,有的种已作为淡水养殖对象。关于鲂属的分类,虽经一些作者整理,但存在不少问题,因而长期未能使用正确的种名。易伯鲁和吴清江(1964)将鲂属鱼类归纳为3种,但个别种的种名厘订有误。Bǎnǎrescu(1970)将华鳊属(Sinibrama)划归为鲂属下的1个亚属,使鲂属共含5个种和亚种。华鳊属的鳔为2室,与鲂属有显著差别,作为亚属对待显然是不妥当的。现根据历年来在各地采得的标本,对鱿属鱼类进行重新整理。计有4种,并对个别种的种名作了订正。    相似文献   

6.
We made a preliminary survey of the present status and ecology of the White-lipped Deer (Cervus albirostris) in the upper Huang He and Chang Jiang River regions of China. Eight mixed herds, ranging in size from 5 to 46 animals each, were observed. The deer lived from the rhododendron scrub just above the spruce forests to alpine grasslands, ranging in altitudes from 4000 to 5000 m. The peak of the rut occurred in October, when breeding herds were composed of a few large stags and hinds. The pasturing of domestic animals in the area influences not only the spatial distribution of the deer, but also the timing of seasonal shifts. The main distribution of the deer is in western Sichuan Province and some scattered populations in Qinghai Province are endangered. The species could survive, given adequate protection.  相似文献   

7.

现生真蕨目马通蕨科(Matoniaceae)植物仅存MatoniaPhanerosorus两属, 集中分布于马来西亚、印度尼西亚等热带地区。马通蕨科植物在中生代时期全球广布, 且主要分布于热带、亚热带地区, 有近9个属, 被作为热带、亚热带气候的标志性植物化石之一。本文梳理总结了中国中生代的马通蕨科化石记录并分析其多样性特征, 共计有2属16种, 包括异脉蕨属(Phlebopteris) 15种和准马通蕨属(Matonidium) 1种。对其化石记录和地质地理分布分析表明, 晚三叠世时期, 异脉蕨属植物广泛分布于热带—亚热带湿热气候区, 包括华南一带的四川、湖北、 云南、西藏、福建等地; 早侏罗世时期, 其分布逐渐向北方扩展, 在南、北方植物区系界线附近均有发现; 中侏罗世局限于湖北、青海等地; 早白垩世时仅在黑龙江和西藏少量发现。准马通蕨属仅在黑龙江地区的早白垩世地层中发现。整体上, 马通蕨科在中国中生代的分布范围变迁与气候带范围变化相吻合。  相似文献   


8.
《Journal of bryology》2013,35(3):165-168
Abstract

The genus Gottschelia Grolle is reported as new to mainland China, from Yunnan Province. Previously G. schizopleura (Spruce) Grolle was the only known Chinese species, reported from Taiwan. However, two further species have recently been found in the Gaoligong Shan range, Yunnan Province, G. patoniae Grolle, Schill & D.G. Long, previously known from the East Himalaya of Nepal and India (Sikkim) and G. grollei D.G. Long & Váňa, described here as a new species endemic to China, the fourth known species in the genus. The differences between the three Chinese species are enumerated with notes on distribution and ecology.  相似文献   

9.
三江源国家公园鸟类物种多样性研究   总被引:5,自引:0,他引:5  
三江源国家公园位于青藏高原腹地,是生物多样性最为集中的区域。为了系统掌握公园内的鸟类分布状况,2015—2017年,对三江源国家公园区域进行了长期的野外调查,结合文献资料,发现三江源国家公园内共分布野生鸟类196种,隶属于18目45科121属。各级保护鸟类59种,占公园鸟类总数的30.1%,其中,国家I级重点保护鸟类8种;国家II级重点保护鸟类27种;青海省级保护鸟类24种。另外,还有国家三有鸟类120种。根据中国物种红色名录,受威胁(濒危、易危和近危)物种有39种,占公园鸟类总数的19.9%。中国特有鸟类15种,占园区内鸟类总数的7.65%。在地理分布型上,三江源国家公园位于古北界青藏区,古北界物种有145种;东洋界物种有37种;广布种有14种。利用G-F指数对物种多样性进行评估,三江源国家公园鸟类的G-F指数为0.825,表明公园内的鸟类物种多样性处于较高水平。长江源园区、澜沧江源园区和黄河源园区的平均动物区系相似性结果表明,三个园区之间动物区系关系均为密切关系。三江源国家公园鸟类物种多样性高、特有种及珍稀濒危物种丰富,具有极高的保护价值和意义。  相似文献   

10.
A new Vietnamese species of the genus Camellia L. (Theaceae, Theoidae) is described and illustrated as C. luteocerata Orel. This species occurs in the rainforests of Lam Dong Province, Vietnam. Morphological characteristics that distinguish it from related Camellia species are presented and discussed. Morphological evidence supports a taxonomic placement in a new section, which is described here as Camellia sect. Dalatia Orel, within C. subgen. Protocamellia (sensu Chang).  相似文献   

11.
The small size, low vagility, territoriality, and reproductive mode of some Amazonian frogs undermine the wide geographical distribution assigned to them. Species with these features represent excellent models for testing the existence of cryptic diversity in widely distributed species. The nurse frog Allobates tinae has recently been described as widely distributed, occurring in various forest types, as well as on both banks of large rivers. Herein, we gather molecular, morphological, bioacoustics, and egg coloration data in order to investigate whether Atinae actually represents a species complex. The sampling effort focuses on ~1,000 km of landscapes in the Purus–Madeira Interfluve (IPM), where two different forest types predominate. We use barcoding algorithm, cluster analysis, and machine learning to test the specific status currently assigned to Atinae. Results were congruent in showing that the two lineages of Atinae occurring in the IPM represent two different species, which can be distinguished from each other by adult morphology, larvae, advertisement call, and molecular data. The species inhabiting open ombrophilous forests in the southern IPM represents Atinae sensu stricto, while the species that inhabits dense ombrophilous forests in the northern IPM represents a new species. We describe this new species and use egg coloration for the first time in the recent taxonomy of Allobates as a diagnostic feature. Additionally, we discuss the importance of egg characteristics on the taxonomy of Allobates and possible ecological reasons for differences observed in the egg melanin ratio between Atinae sensu stricto and the new species.  相似文献   

12.
Mashhor Mansor 《Hydrobiologia》1996,340(1-3):121-125
After ten years of field surveys on various water bodies ranging from stagnant water ponds, pools and man-made lakes to flowing waters such as rivers, streams and canals, there is a clear evidence of four problematic weeds in Malaysia. These species are Eichhornia crassipes, Salvinia molesta, Lemna perpusilla, and Pistia stratiotes. Among these weeds, E. crassipes and S. molesta are widely distributed througout Malaysia. E. crassipes generally dominates canals and rivers although, recently, this species has spread to man-made lakes. The favourable tropical climate and conducive environmental factors help to trigger the massive growth of these weeds. The high nutrient concentrations, notably phosphate which has a soluble reactive concentration greater than 0.1 mg l–1, initiate a high productivity. Manual control methods are generally used and several herbicides including 2,4-D and glyphosate are frequently employed to eradicate these weeds.  相似文献   

13.
《Journal of bryology》2013,35(3):179-188
Abstract

Two new species of Schistidium Bruch & Schimp., S. riparium H.H.Blom, Shevock, D.G.Long & Ochyra, and S. mucronatum H.H.Blom, Shevock, D.G.Long & Ochyra, are described and illustrated. They occur in rheophytic habitats in China, S. riparium in the southern Hengduan Mountains in Yunnan Province (Lancang Jiang and Nu Jiang catchments) and S. mucronatum from further north, on the Qinghai–Tibet Plateau of Sichuan and Qinghai Provinces (Jinsha Jiang and Huang He catchments). The affinities of the new species are discussed and on the basis of their concave and broadly canaliculate leaves with plane and erect margins, S. riparium is tentatively placed in Schistidium Bruch & Schimp. subgen. Canalicularia Ochyra, whereas S. mucronatum on account of its keeled, ovate-lanceolate leaves and the strongly curved and twisted peristome teeth resembles very much species of sect. Apocarpiformia (Kindb.) Ochyra within subgen. Apocarpa Vilh.  相似文献   

14.
Andrés Boltovskoy 《Grana》2013,52(2-3):98-107
Glochidiniumgen. nov., a ncw genus of Peridiniaceae based on Peridinium penardiforme Lindemann, is herewith erected. Its plate formula is: Po+X+4′+6′′+3C+4S+5′′′+2′′′′ Main diagnostic characters of this new genus are the presence of only 3 cingular plates (it lacks the transitionalone), the third cingular contacting the anterior sulcal plate, and an unusual sulcus holding a small triangular posterior sulcal plate. The thecal morphology and structure of two freshwater planktic species of the genus are described on the basis of LM and SEM observations. G. penardiforme comb. nov. is an infrequent species, albeit widely distributed world-wide. It has been recorded under the names of Peridinium, Glenodinium and Peridiniopsis. Peculiar features in the tabulation of the furrows and of the surface sculpture show that the species does not fit any of the known genera, for which reason the new genus Glochidinium is established. G. platygaster sp. nov., the second species included in the genus, differs from the former by its elongated body, the regular pentagonal shape of its large first apical plate, an equally large sulcal anterior plate, and well developed sculpture, chiefly on the antapical plates. Glochidinium penardiforme and G. platygaster were found in some reservoirs from central and northern Argentina. G. penardiforme was also found in several Argentine rivers and ponds.  相似文献   

15.
The distribution of many fishes that occupy large rivers is poorly known, in part due to the difficulties of sampling for them. This is especially true for small-bodied or rare species, such as the snail darter Percina tanasi, 44, 469–488; 1976). This federally listed (threatened) species has a limited distribution in the Tennessee River system in Alabama and Tennessee, where it is known from a few large tributaries or small rivers. In Alabama, P. tanasi was previously known from only one locality, but has recently been found in two additional, widely separated systems. These new records raise questions regarding the accuracy of our current understanding of the range for this species. Particularly, is P. tanasi present throughout the main stem Tennessee River, and is this species dispersing into new areas from source populations in the river? To clarify the distribution of P. tanasi in Alabama, 83 unique sites were surveyed using environmental DNA analysis. This cost-effective detection tool reduces the difficulty associated with empirically sampling large rivers for small fishes. Approximately 42% of sites sampled were positive for P. tanasi DNA. This study confirmed the known localities of P. tanasi in the Bear Creek, Elk River and Paint Rock River. Several new localities were also discovered throughout the main stem Tennessee River and in Shoal Creek, near Florence, Alabama. These findings can inform biologists about where to prioritize conservation efforts and further could lead to studies assessing movement and relatedness between populations in this system.  相似文献   

16.
Korovchinsky  N. M. 《Hydrobiologia》2000,441(1):73-92
The poorly known D. dubium Manuilova is redescribed on extensive material from more than 80 populations from the Russian Far East, Central Asia, Mongolia, China, Japan, Vietnam, the Philippines, Thailand, Malaysia, Bangladesh, India and Sri Lanka. Its morphological variability and geographical distribution are analysed and supplemented by notes on biology. The conspecificity of morphologically different distant populations is discussed. In the northern part of its range, D. dubium was long confused with D. brachyurum or D. leuchtenbergianum, and in the south with D. modigliani. It seems that the recent appearance of D. dubium in fish ponds of Uzbekistan and Kazakhstan was an introduction, together with Far Eastern fish. D. pseudodubium sp.nov., close to but markedly different, is described from two lakes in the lower Amur river system. D. dubium, D. pseudodubium, D. tropicum and D. modigliani s. str. form a group of related species, widely distributed in Eastern and Southern Asia.  相似文献   

17.
18.
《Journal of bryology》2013,35(3):192-201
Abstract

Morphologically unique specimens of Mesoptychia (Lindb.) A.Evans recently collected in Guizhou Province, China were sequenced and analysed using a combined trnL-F+trnG-intron cpDNA dataset from 10 known taxa of Mesoptychia. Using a combination of morphological and molecular data, Mesoptychia chinensis Bakalin, Vilnet & Xiong sp. nov. is described as new to science. Mesoptychia polymorpha subsp. pakistanica Bakalin & Vilnet subsp. nov. is established based on morphological data only. Mesoptychia ussuriensis is newly recorded for China. New molecular data for species delimitation within Mesoptychia distributed in southern and south-east Asia are provided.  相似文献   

19.
20.
Palaeoxenus sinensis Chang, Muona & Teräväinen sp. nov. (Coleoptera, Eucnemidae) is described on the basis of a Cretaceous larva found from the Yixian Formation in Huangbanjigou, Liaoning Province, China. The only previously known member of this clade is a southern Californian endemic, Dohrn's elegant eucnemid beetle (Palaeoxenus dohrni), a species that develops in conifers, especially the incense cedar (Calocedrus decurrens). The new find proves that the highly specialized main eucnemid lineages had evolved 123 Mya, before the main radiation of the angiosperms and probably as an adaptation to development in gymnosperms.  相似文献   

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