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1.
Available information about Mediterranean tardigrades regards mainly the insular and peninsular Italian coasts, but also Malta, the Alboran Sea, Spain, France, Albania, Morocco, Algeria, Tunisia, Cyprus, and Lebanon. The Mediterranean Tardigrades, more than 70 species, are Heterotardigrada, mainly the order Arthrotardigrada with several families, and the order Echiniscoidea with only the family Echiniscoididae. Coralligenous detritus seems to be the most favourable kind of sediment in which the highest values of biodiversity are reached. Halechiniscidae is the most important family in the subtidal zone, whereas Batillipedidae are more frequent in the intertidal zone. A study of 4 submarine cave populations has been carried out. Neoarctidae and Neostygarctidae, considered as the most ancient families, have only been found in the Mediterranean Sea to date. This could mean that Arthrotardigrada originated in the old Thetys Sea from which the basin of the Mediterranean Sea was formed.  相似文献   

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江西省缓步动物四个新纪录种记述   总被引:7,自引:0,他引:7  
郁笛 《四川动物》2006,25(3):533-536
本文报道了江西省缓步动物4个新记录种:双裂角棘影熊虫Cornechiniscus lobatusRamazzotti,1943(异缓步纲,棘影熊虫科),节值大生熊虫Macrobiotus harmsworthiMurray,1907(真缓步纲,大生熊虫科),胡氏大生熊虫Macrobiotus hufelandiSchultze,1833(大生熊虫科)和杜氏高生熊虫Hypsibius dujardiniDoyére,1840(高生熊虫科)。  相似文献   

4.
Five cruises to the Faroe Bank in the northeast Atlantic revealed a rich loriciferan fauna inhabiting shell gravel to fine carbonate sand. This paper describes two new species of Pliciloricus found at depths of 120-260 m. Currently, only six species of this genus have been described from various localities around the world, but several new species are currently being described. The diagnosis of the genus Pliciloricus is emended to include the two new taxa. The first of the two new species Pliciloricus leocaudatus sp. n. is characterized by having four new kinds of scalids in the second row and an additional row of alternating plates in the eighth row. The second species Pliciloricus shukeri sp. n. is characterized in having a secondary double organ in the third row. The morphology of the two species, including the new structures, has been investigated using LM and scanning electron microscopy. Conclusively, the scalid pattern of the introvert of Pliciloricus has been re-evaluated, due to the finding of the new structures. Additionally, a discussion of the life cycle of the genus Pliciloricus is given, since the postlarval stage is reduced in both new species.  相似文献   

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The tardigrade fauna of the African continent is reviewed and presented graphically using Worldmap, a Geographical Information System (GIS) developed for exploring geographical diversity patterns in large biological datasets. References to the African tardigrade fauna have been gathered from published literature and supplemented with unpublished species information from the collection of Prof. Reinhardt M. Kristensen (RMK), Zoological Museum, University of Copenhagen. 156 species belonging to 36 genera of tardigrades are present. They consist of 105 eutardigrade species and 51 heterotardigrade species, of which 42 species are semiterrestrial and 9 species are marine. The presence of tardigrades are reported from 20 countries, but of these 9 are represented by a single reference. Marine tardigrades in particular have been neglected, with only a single report from the shores of the African continent. Data from the RMK collection of samples from Egypt is included in the analysis.

The scattered and sparse knowledge of the African tardigrade distribution makes general conclusions difficult, but emphasises the large regions which require further investigation. The current distribution patterns corresponds with easy accessible or ‘tourist’ locations. Regions where GIS could be used to illustrate ecological preferences are also pointed out by the analysis.

Isohypsibius malawiensis sp. n. is described from Lake Malawi. It has a smooth body surface and lacks eyes. The heteronych claws are without lunulae, but below the claws a double arched cuticular bar is present. The dorsal and ventral apophyses of the buccal tube have a large drop-shaped swelling. The first macroplacoid is the largest followed by the second, which is only slightly larger than the third; microplacoid is absent. Males are smaller than females. Females lay only one to two very large eggs in the exuvium. The Malpighian tubules are clover-shaped. The new species is interstitial in coarse sediment and no other tardigrade species were present.  相似文献   


7.
广西十万大山地区兽类区系及动物地理研究初报   总被引:5,自引:1,他引:4  
1997-2000年对广西十万大山地区兽类进行了实地考察,并结合历史资料进行鉴定和分析,初步查明十万大山地区共有兽类81种,分别隶属9目23科55属,占广西全省兽类种类的55%,其中拥有国家一级保护动物5种,二级保护动物14种,广西省地方重点保护动物20种。  相似文献   

8.
The biology and ecology of lotic Tardigrada   总被引:3,自引:0,他引:3  
  • 1 Tardigrades comprise a micrometazoan phylum that is a sister group of the arthropods.
  • 2 They are components of the meiobenthos in lotic habitats, and ≈ 50–70 species have been reported in such habitats world‐wide. Approximately 800 species have been identified from all marine, freshwater, and terrestrial habitats.
  • 3 Taxonomy is based primarily on the morphology of the claws, buccal‐pharyngeal apparatus, cuticle and eggs.
  • 4 Reproductive modes include sexual reproduction (amphimixis) and parthenogenesis. The sexual condition of individuals may be either gonochorism, unisexuality, or hermaphroditism. Moulting occurs throughout the life of the tardigrade.
  • 5 Latent states (cryptobiosis, including encystment, anoxybiosis, cryobiosis, osmobiosis and anhydrobiosis) enable tardigrades to withstand unfavourable environmental conditions.
  • 6 Population densities, life histories, dissemination and biogeography of freshwater species are poorly known.
  相似文献   

9.
四川冶勒自然保护区兽类区系调查   总被引:4,自引:2,他引:2  
张君  胡锦矗 《四川动物》2004,23(2):137-141
2002年8月、10月、2003年1月对冶勒自然保护区的生物资源进行了综合科学考察,同时结合有关资料,对该地兽类区系进行研究。表明冶勒保护区迄今发现有兽类7目25科62属91种,国家Ⅰ级保护5种,Ⅱ级保护18种,四川省重点保护的兽类有7种,属于国家保护有益的或者有重要经济、科学研究价值的兽类27种,我国特有物种29种。区系组成以东洋界成分为主,并出现南北交错的现象。  相似文献   

10.
在不同季节通过定点和随机采集相结合,对梵净山土壤甲螨进行了调查,共得到甲螨标本11 487号,分属于45科81属.在世界动物地理区划中,以世界广布类群、东洋-古北界区系型类群和东洋界特有类群为主体;跨古北界的区系型中所包含类群所占比例最高.在中国动物地理区划中,以华中区独有类群、华中-华南区系型类群和华中-东北区系型类群为主体.含东北区跨区区系型类群最多.  相似文献   

11.
The copepod community on the Faroe shelf is dominated by Calanus finmarchicus, Temora longicornis, Acartia longiremis and Pseudocalanus spp. The species composition, abundance and development of the copepod community varied considerably during the season 2004. These variations reflected to a large extent the different life strategies of the copepods. Both nauplii and copepodites of C. finmarchicus were most abundant during spring and early summer. The two neritic copepods T. longicornis and A. longiremis were present in low numbers during spring but dominated the copepod community later during the productive period. Pseudocalanus spp., on the other hand, occurred throughout the year, but showed no clear numerical response in abundance to the spring bloom. The egg production measurements of C. finmarchicus and T. longicornis showed some pre-bloom egg production, but as the spring bloom started the egg production rate increased significantly, especially for C. finmarchicus. There seemed to be a substantial loss of nauplii and copepods from the shelf ecosystem during the productive season. It was, however, not possible to determine whether this was mainly due to mortality or advective loss.  相似文献   

12.
大川河鱼类区系及其群落生态结构的研究   总被引:1,自引:0,他引:1  
周仰jin  吴万荣 《生态学杂志》1991,10(2):20-24,71
鱼类区系及其群落生态结构,在理论和实践上都有十分重要的意义。但是,关于鱼类区系的生态结构问题,还未见详细报道。本文通过对大川河鱼类区系及其群落生态结构的分析,探讨鱼类区系及其群落生态结构的规律。  相似文献   

13.
This paper deals with a method of employing videomicroscopy in the study of meiofauna. The apparatus is inexpensive, easy to use, and offers a high degree of resolution. Accurate measurements of the specimen can be made directly from the video monitor screen. With the addition of a videocassette recorder, live footage can be recorded for analysis, correspondence, or as an aid in teaching.  相似文献   

14.
泸沽湖鱼类区系现状及人为影响成因的初步探讨   总被引:3,自引:0,他引:3  
泸沽湖是位于滇西北的一个断陷湖泊,为滇川两省共有。文献记录泸沽湖原始的鱼类区系由4种鱼类组成,隶属于裂腹鱼属和泥鳅属。于2001 ,2002和2004年3次考察泸沽湖,进行标本采集和鱼类区系现状调查。查看了采自泸沽湖的鱼类标本518号,结合历史上的采集记录和大量相关文献,确定泸沽湖记录有鱼类12种,隶属于3目4科10属;过度捕捞和毁林造成的泥石流是泸沽湖鱼类区系变化的主要原因。  相似文献   

15.
Tardigrades are a phylum of microscopic invertebrates with a global distribution. Although our understanding of their systematic position and taxonomy has increased and continues to grow, their relationship with the other organisms that share their habitat remains poorly studied. One such organism is Propyxidium tardigradum, a peritrich ciliate which uses tardigrades for dispersion and as a substrate for reproduction. Here, we present the first Scottish record and tenth global occurrence of Propyxidium tardigradum, thereby expanding our knowledge of its poorly understood zoogeographic distribution. We also summarise the literature concerning P. tardigradum biology, proffer hypotheses regarding the Propyxidium-tardigrade relationship, and the apparent lack of heterotardigrade ciliate infestation. Additionally, we indicate a number of recommendations for the direction of future studies regarding the ciliate. Finally, we add a further three species, Milnesium variefidum, Hypsibius cf. scabropygus and Macrobiotus scoticus to the list of Propyxidium host species.  相似文献   

16.
The muscular system of the marine interstitial gastrotrich Draculiciteria tessalata (Chaetonotida, Paucitubulatina) was analyzed with fluorescent phalloidin. Muscles in circular, longitudinal, helicoidal and dorsoventral orientations were found. Circular muscles were present as discreet rings on the pharynx only. Five pairs of longitudinal muscles were found in dorsal, lateral and ventral positions. One of the two pairs of lateral muscles is newly described for the species. Helicoidal muscles, external to the circular muscles and some longitudinal bands, spiraled around the pharynx and anterior portion of the intestine. Two pairs of segmentally-arranged dorsoventral muscles were also present. Lateral dorsoventral muscles extended from the base of the pharynx to the anterior part of the caudal furca. Medial dorsoventral muscles extended from the pharyngeal-intestinal junction into each ramus of the caudal furca. A hypothesis on the evolution of dorsoventral muscles in D. tessalata is proposed which includes a splitting of circular muscles into separate somatic and splanchnic components with a further displacement of both muscle sets into a dorsoventral orientation.  相似文献   

17.
This is the first published report of tardigrades in Newfoundland and Labrador. Twenty-six species have been identified so far, including four new records for Canada and one new record for North America. Although there is some overlap of species with those found in earlier Canadian studies, there are some interesting discrepancies. The rare occurrence and restricted distribution of the very few heterotardigrades (three species and 30 specimens) found so far in Newfoundland is noteworthy, as is the occurrence of several tardigrade species whose former records have been mainly for Greenland. It appears the environmental conditions in Newfoundland can support a number of species that would normally be restricted to a more northerly distribution. A comparison of the species found in Newfoundland with those of a number of other northern countries suggests that the Newfoundland species are most similar to those found in Greenland and mainland Canada.  相似文献   

18.
黑石顶自然保护区两栖动物资源和区系特征的研究   总被引:3,自引:0,他引:3  
常弘  林术 《生态科学》1997,16(1):40-44
报道了黑石顶自然保护区两栖动物资源和区系特征的调查结果.已知有21种(包括亚种)11属7科2目.在21种两栖动物中,它们都属于东洋界物种,其中华中区和华南区的共有物种占61.8%,而属华中区的物种占19.1%属华南区的物种也占19.1%.还分析了黑石顶自然保护区两栖动物群落的水平分布和垂直分布的特征  相似文献   

19.
中国金沙江一级支流牛栏江的鱼类区系分析   总被引:1,自引:0,他引:1  
2006年11月和2008年10月,对云南省牛栏江流域进行考察,共采集到鱼类标本42种,结合历史记录和中国科学院昆明动物研究所鱼类标本馆馆藏的鱼类标本,整理出牛栏江鱼类名录。在剔除引入种的基础上,采用按所含种属的绝对数目进行排序的传统方法和区系存在度方法对目、科、属级水平进行排序,分析牛栏江鱼类区系组成特点。两种方法结果相差甚远,结果显示:在传统排序方法中的优势科属,即一些世界性分布的科和属,在牛栏江分布的种类并不很多,区系存在度相应较低。相反,一些具有地方性分布和小的科和属,其区系存在度相对较大。显然,以区系存在度分析所得结果更能反映牛栏江流域鱼类区系组成特点。两种方法相结合,分析牛栏江的鱼类区系成分,并与金沙江中下游(石鼓至宜宾段)鱼类区系相比较,表现出高度的相似性。  相似文献   

20.
Potential effects of climate change on plant species in the Faroe Islands   总被引:3,自引:0,他引:3  
Aim To identify the effect of climate change on selected plant species representative of the main vegetation types in the Faroe Islands. Due to a possible weakening of the North Atlantic Current, it is difficult to predict whether the climate in the Faroe Islands will be warmer or colder as a result of global warming. Therefore, two scenarios are proposed. The first scenario assumes an increase in summer and winter temperature of 2 °C, and the second a decrease in summer and winter temperature of 2 °C. Location Temperate, low alpine and alpine areas in the northern and central part of the Faroe Islands. Methods The responses of 12 different plant species in the Faroe Islands were tested against measured soil temperature, expressed as Tmin, Tmax, snow cover and growing degree days (GDD), using generalised linear modelling (GLM). Results The tolerance to changes in winter soil temperature (0.3–0.8 °C) was found to be lower than the tolerance to changing summer soil temperature (0.7–1.0 °C), and in both cases lower than the predicted climate changes. Conclusions The species most affected by a warming scenario are those that are found with a limited distribution restricted to the uppermost parts of the mountains, especially Salix herbacea, Racomitrium fasciculare, and Bistorta vivipara. For other species, the effect will mainly be a general upward migration. The most vulnerable species are those with a low tolerance, especially Calluna vulgaris, and also Empetrum nigrum, and Nardus stricta. If the climate in the Faroe Islands should become colder, the most vulnerable species are those at low altitudes. A significantly lower temperature would be expected to produce a serious reduction in the extent of Vaccinium myrtillus and Galium saxatilis. Species like Empetrum nigrum, Nardus stricta, and Calluna vulgaris may also be vulnerable. In any case, these species can be expected to migrate downwards.  相似文献   

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