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1.
The complex study, including allozyme variability and cytometry of hybrid populations of green frogs Pelophylax esculentus (L., 1758) complex has confirmed that the only region of Ukraine where allodiploid are encountered frequently is the Severski Donets basin (9% of all hybrids). In other areas, only two polyploidy hybrids (0.9%) and one probably autopolyploid individual of each parental species have been registered. According to allozyme specters, all three polyploidy hybrids from the Severski Donets basin were males and belonged to biotype P. esculentus (=lessonae) — 2 ridibundus, and their population in this region has halved during the past decade.  相似文献   

2.
Hybridization and polyploidy play an important role in animal speciation. European water frogs of the Pelophylax esculentus complex demonstrate unusual genetic phenomena associated with hybridization, clonality and polyploidy which presumably indicate an initial stage of reticulate speciation. The Seversky Donets River drainage in north‐eastern Ukraine is inhabited by both sexes of the diploid and triploid hybrid P. esculentus and only one parental species Pelophylax ridibundus. Based on the presence of various types of hybrids, all populations studied can be divided into three geographical groups: I) P. ridibundusP. esculentus without triploids; II) P. ridibundusP. esculentus without diploid hybrids; and III) P. ridibundusP. esculentus with a mixture of diploids and triploids. A study of gametogenesis revealed that diploid P. esculentus in populations of the first type usually produced haploid gametes of P. ridibundus and a mixture of haploid gametes that carried one or another parental genome (hybrid amphispermy). In populations of the second type, hybrids are derived from crosses of P. ridibundus males with triploid hybrid females producing haploid eggs with a genome of P. lessonae. Therefore, we suggest that clonal genome duplication in these eggs might be the result of suppression of second polar body formation or extra precleavage endoreduplication. In populations of the third type, some diploid females can produce diploid gametes. Fertilization of these eggs with haploid sperm can result in triploid hybrids. Other hybrids here produce haploid gametes with one or another parental genome or their mixture giving rise to new diploid hybrids.  相似文献   

3.
The Rectogordius (Foraminifera) abundance zone is described in the east of the Shishtu village in the Ozbak Kuh Mountain. The samples were collected in the Zaladou Formation., which is 60 m thick and composed of shales, sandstones, sandy limestones, microconglomerate, bioclastic limestones, coral limestone and fusulinid limestones. The Rectogordius abundance zone was found in sandy bioclastic limestone. It displays two species and three subspecies of this foraminifer, including Rectogordius iranicus, R. iranicus gadukensis, R. minimus and R. minimus shishtuensis n. subsp., R. iranicus ozbakensis n. subsp. The age of this abundance zone is considered to be Gzhelian, due to the distribution of Rectogordius in Central Iran (Ozbak Kuh; Zaladou Formation), central and eastern Alborz (Emarat Fm.), Sanandaj-Sirjan zone (Vazhnan Formation), as well as in the Donets, Arctic Canada, Afghanistan, and the Carnic Alps. The genus Rectogordius is possibly restricted to the northern Paleotethys margin, northern Cimmerian margin, shelf of the Uralian Ocean as far as the northernmost part of North America. Two new subspecies Rectogordius minimus shishtuensis n. subsp. and Rectogordius iranicus ozbakensis n. subsp. are described.  相似文献   

4.
5.
A new species and genus of Choristitinae, Adventochoristites abavus gen. et sp. nov., is described from the Upper Serpukhovian of the Donets Basin and is considered as an ancestor of the Middle-Late Carboniferous Choristites linage. The characteristic features differing Alphachoristites from Choristites and Trautscholdia are specified. New species Alphachoristites berestovensis sp. nov. and Quizhouspirifer tshaikensis sp. nov. are established.  相似文献   

6.
New finds of Late Palaeozoic arachnids, based on three well-preserved carapaces from the Carboniferous of Russia and Ukraine and one complete, albeit poorly preserved, specimen from the Permian of Kazakhstan, are described. The spider genus Arthrolycosa is reported from the Late Carboniferous (Late Pennsylvanian: Kasimovian–Gzhelian) of Chunya in the Tunguska Basin of Siberia; it is the first find of a spider outside the Carboniferous tropics. Another fossil assigned to the same genus comes from the Late Carboniferous (Early Pennsylvanian: Bashkirian) of Kamensk–Shakhtinsky in the Donets Basin of Russia; it is probably the oldest fossil spider known. A thelyphonid (whip scorpion) carapace is described from the Late Carboniferous (Late Pennsylvanian: Kasimovian) of the adjacent Lugansk Province of the Donets Basin of Ukraine.  相似文献   

7.
Studies carried out for more than 10 years by the Task Group to establish GSSPs at the base of the Moscovian–Kasimovian and Kasimovian–Gzhelian boundaries have resulted in the proposal that the level at which the conodont species Idiognathodus simulator (Ellison, 1941) first appears be selected to mark the base of the Gzhelian Stage. This expands this eastern European chronostratigraphic unit to a global scale.I. simulator (sensu Barrick et al., 2008) has been identified so far in Midcontinent and eastern North America, the Moscow and Donets basins and southern Urals of eastern Europe, and in south-central China. Correlation of this level based on this species and other conodont species can be reinforced in some areas by ammonoid and fusulinid data.  相似文献   

8.
Research of the alleles of the species-specific genes in the gametal cells of Rana kl. esculenta hybrids proved the existence of three local populations within the territory of Ukraine. Their hybrids reject either the genome of lake frog (Danube lowland), either the previous one or another one genome (basin of Severskiy Donets river), either the genome of pond frog (the residuary territory of the areal). The research of skin transplants rejection of hybrids' parental species has shown that despite the orientation of genome elimination of this population the graft of lake frog always starts identifying and rejecting earlier. That is why the genetic skewness of hybrids becomes apparent at the skin level and corresponds to its manifestations at the organism level.  相似文献   

9.
Eurypterid finds are described from the Carboniferous (Kasimovian) localities Lomuvatka (Luhansk Region, Ukraine) and Kakichev (Rostov Region, Russia). These eurypterids are supposedly juveniles of Adelophthalmus carbonarius Chernyshev, 1933, the only eurypterid previously described from the Donets Basin.  相似文献   

10.
An important late Moscovian rugose coral association is described from the Rod El Hamal Formation of the Wadi Araba area (northern Eastern Desert, Egypt). The upper part of the formation yielded a moderately abundant but poorly diversified coral fauna composed of large dissepimented solitary rugose corals. In total, six species belong to the Bothrophyllidae and the Geyerophyllidae, including three new species: Bothrophyllum suezensis, Bothrophyllum cylindricum, and Amygdalophylloides omarai. Three undeterminable Bothrophyllidae taxa are left in open nomenclature. The corals were attached to the soft substrate by talons and rootlets, either rooted and growing upward as mud-stickers or as secondary recliners. They show frequent rejuvenations and constrictions. Encrustation and/or bioerosion are scarce. Carbonate microfacies indicate a habitat in littoral and inner neritic zones adjacent to a low terrigenous hinterland. Colonial taxa are missing and tabulate corals are rare. The corals from the Rod El Hamal Formation are the only example of a late Moscovian coral fauna on the southern margin of the Palaeotethys, that is to say along the northern margin of Gondwana. The association shows similarities with northwestern Spain (Cantabrian Mountains), the Donets and Moscow basins, and thus a general attribution to the Palaeotethys realm.  相似文献   

11.
北京山区与城区植物组成比较   总被引:1,自引:0,他引:1  
邢韶华  肖雁青  林大影  袁秀  崔国发   《广西植物》2007,27(3):487-492
通过典型抽样法对北京山区与城区植物物种进行了调查,结果表明北京山区有植物种1283种,隶属于127科,538属,北京城区(五环内)共有维管束植物99科,307属,536种。含25种以上的科的数量在北京山区和城区都比较少,含5种以下的科的数量在北京山区和城区都比较多,而城区只含有1种植物的科要比山区多一些。植物种在属上的分布与其在科上的分布相似。城区植物中乔木、灌木和多年生草本和一年生草本的比例相差不大,而在山区,多年生草本植物优势极为明显,也是山区和城区植物种数差异的主要来源。在属级水平上,植物区系中温带成分在北京山区和城区均占有绝对优势,二者的差异主要表现在城区植物的热带成分明显高于山区,而温带成分的比例则要稍低于山区。山区和城区共有植物有329种,隶属于72科,201属。主要集中在菊科、禾本科、蔷薇科等世界性大科中。  相似文献   

12.
Although zonation patterns of the standing vegetation along a water depth gradient in wetlands have been well described, few studies have explored whether such patterns also occur in the seed bank. This study examined patterns of the seed bank along a water depth gradient in three vegetation types (submerged zone, floating-leaved zone, and emergent zone) of a subtropical lakeshore marsh, Longgan Lake, China. Submerged zone is the deepest water and never exposed its soil to air, and was dominant by submerged species; floating-leaved zone is waterlogged soil even during drawdown and was dominant by Nelumbo nucifera; emergent zone is rarely exceeded 1 m water depth during the wet season (summer and autumn), and the marsh soil was usually exposed to air during drawdown (winter and spring), and is dominant by Zizania latifolia, Polygonum hydropiper and Scirpus yagara. It was found that many species were ubiquitous in the seed bank. Frequency of distribution and densities of the dominant species, however, varied significantly from zone to zone. A total of 22 species was recorded in submerged zone, 20 in floating-leaved zone, and 29 in emergent zone. Germinated seedling density was 1,580, 8,994 and 20,424 seedlings m−2 in submerged zone, floating-leaved zone, and emergent zone, respectively. Submerged and floating-leaved species were significantly abundant in the submerged zone, while the emergent species were found predominantly in the emergent zone. A fern species, Ceratopsis pterioides, was the most abundant seedling in seed banks from all three zones. A TWINSPAN dendrogram and CCA ordination diagram clearly showed separation of species among sites with the emergent zone being well separated from the submerged zone and floating-leaved zone, thus revealing marked zonal patterns in species distributions in the seed bank. This pattern of zonation reflected the pattern in the standing vegetation.  相似文献   

13.
New bryozoans characterized by a bilateral vertical colonies colonies—Cardioecia refuga sp. nov. (Tubuliporida), Elea lyapini sp. nov., E. troshkovensis sp. nov., and E. taylori sp. nov. (Melicerititida) from Middle Jurassic (Middle Callovian) of the Moscow region (Russia), and Biforicula legitima sp. nov. (Melicerititida) from the Upper Cretaceous (Lower Campanian) of the Southern Donets Basin (Ukraine)—are described. All species described in this paper belong to genera that have been recorded for the first time in the East European Platform. Some morphological structures in the colonies of these bryozoans and some distinctive features of the order Melicerititida that emphasize the difference of this order from bryozoans of other orders of the class Stenolaemata are examined.  相似文献   

14.
《Palaeoworld》2016,25(4):581-599
Six Early Carboniferous brachiopod species in four genera of the Superfamily Spiriferoidea are described from the Qaidam Basin, northwestern China, including a new genus, Qaidamospirifer, and two new species: Grandispirifer qaidamensis and Qaidamospirifer elongatus. Additionally, a new genus, Triangulospirifer, is also proposed to replace Triangularia Poletaev, 2001 that was preoccupied by a Devonian molluscan genus.On the basis of the new material as well as published information, we have reviewed the taxonomic composition and the stratigraphic and palaeobiogeographic distributions of the three previously established genera from the viewpoint of palaeobiogeography. The study reveals that Grandispirifer has a relatively long stratigraphic range from the late Tournaisian to Serpukhovian. During this interval, the genus attained a wide geographical distribution, reaching Northwest China, western Yunnan of West China, Japan, as well as Iran and North Africa. Angiospirifer first occurred in western Europe in the Viséan, and later migrated to North Africa during the late Viséan. In the Serpukhovian, it migrated eastward, reaching the Donets Basin of Ukraine and the Qaidam Basin in Northwest China. Anthracothyrina evolved from Brachythyrina in North Africa in late Viséan, then dispersed north-westward to western and eastern Europe and, further eastward to the Qaidam Basin during the Serpukhovian.  相似文献   

15.
利用巴氏罐诱法,对山西庞泉沟国家自然保护区的不同功能区——核心区(绿色长廊)、缓冲区(八道沟)、远离农田实验区(神尾沟)及靠近农田实验区(八水沟)——林地地表甲虫步甲物种多样性进行了调查和比较,目的在于探明该保护区有代表性林地步甲物种的组成及受不同程度人为干扰下的多样性格局。结果表明:(1)本研究共捕获步甲物种42种,38种是该保护区的新记录种类,其中粗皱步甲Carabus crassesculptus和沟步甲C. canaliculatus 为优势种,与尖角通缘步甲Pterostichus eschscholtzii,强足通缘步甲P. fortipes,罕丽步甲C. manifestus和长叶步甲C. vladimirskyi一起构成研究地的常见种。(2)不同功能区物种组成和数量分布各不相同,多样性各项指标均是靠近农田的实验区最高,核心区最低。(3)各功能区具有特有的指示性种类,其中黄条春步甲Notiophilus reitteri为核心区指示种; 凹唇春步甲N. impressifrons 为缓冲区指示种; 粒步甲C.granulatus,刻翅步甲C.sculptipennis 和中华通缘步甲P.chinensis为实验区指示种。(4)群落相似性分析表明缓冲区与核心区及远离农田实验区之间具有较高的相似性,靠近农田实验区与其他3个地点相似性较低。结果提示适度干扰可提高物种丰富度,但降低人为干扰(如旅游和交通压力)有利于步甲多样性的保护。  相似文献   

16.
贺兰山天牛科昆虫区系组成及垂直分布   总被引:1,自引:0,他引:1  
2013-2015年对贺兰山不同海拔和垂直植被带的天牛科昆虫进行系统调查,结果表明:贺兰山共有天牛科昆虫6亚科31属45种,其中,沟胫天牛亚科属、种数最多,有14属21种,其种数占总种数46.67%,天牛亚科有9属12种,幽天牛亚科有4属5种,花天牛亚科有2属4种,锯天牛亚科2属2种,膜花天牛亚科仅有1属1种。区系组成上,古北界有17种,占总种数的37.78%,其中中亚成分占35.29%,广布型28种,占总种数的62.22%。在我国昆虫地理区划中的分布共有13个分布类型,全国广布型最多,占总种数的20%。以蒙新区种类为主体,并与东北区和华北区关系密切联系。在垂直分布上,以山前阔叶林带采集到的天牛种类最多,有22种,占总数的48.89%;从低海拔的山前荒漠半荒漠带到高海拔的山地针叶林带,天牛物种数量逐渐增加;除山地草原带外,随海拔增高,古北界种类逐渐增多。通过聚类分析显示,山地针叶林带和针阔混交林带天牛种类组成相似性较高;山地灌丛带、山地疏林带和山前阔叶林带相似性较高;山前荒漠半荒漠带、山地草地带与其他植被带天牛组成差异较大。  相似文献   

17.
A total of 551 species from 10 families of phytophagous beetles (superfamilies Chrysomeloidea and Curculionoidea) have been recorded in the steppe communities of the High Trans-Volga forest-steppe zone, 62% of which belong to the steppe landscape-geographic complex. The vast majority of the species belong to three families: Curculionidae (254 species; 46%), Chrysomelidae (186 species; 34%), and Apionidae (51 species; 9%). The regional steppe fauna has a complex arealogical structure combining the Western Scythian and Sarmatian elements, as well as relict species of the Angarian origin and some Eastern European ones. The highest diversity of phytophagous beetles is observed in the zonal meadow steppe communities (299 species; 54%). The most specific are the petrophilous steppe complexes which also include the greatest number of relict forms. Xerophilous Kazakhstan- Turanian species are mostly concentrated in the saline steppe communities of the southernmost forest-steppe zone. The species diversity is also high (249 species) in the open ruderal communities dominated by species characteristic of the pioneer stages of the steppe successions. Some steppe reservations include over 50% of the entire regional fauna of phytophagous beetles. The species diversity in the steppe localities decreases northward due to a gradual decrease in the number and proportion of the Scythian species: from 55% in the middle of the foreststeppe zone to 36% near its northern boundary. The species diversity of the slope communities in the forest-steppe zone is at least not lower than that in the similar areas of the steppe zone. The ratio of the number of Curculionoidea species to that of plant species is very high, reaching about 3: 4 in the model steppe localities of the High Trans-Volga forest-steppes, as compared to 1: 2 in the zonal steppe communities (according to the published data). The data considered confirm the significance of the forest-steppe zone as an important biodiversity center in the East European Plain and as a reservation of relicts of different origins.  相似文献   

18.
2000~2004年对云南省恙螨进行调查,发现云南省内恙螨192种,主要分布于中西部及中南部的热带及亚热带气候区,垂直高度多在1 000 m以下或1 500~2 500m范围.古北界种类有114种,占59%,东洋界种类较少为6%,35%的种类为跨界分布.中华纤恙螨leptotrombidium sinicum和小板纤恙螨L.scutellare为优势螨种.结合其他资料发现,该省广布种类10种,特有种5种,广宿主种及窄宿主种类均较多.少数螨种仅发现于3000 m以上的高海拔温带气候区或500m以下的低海拔热带气候区.恙螨分布与地域、海拔及气候因素有关.  相似文献   

19.
小叶、中间和柠条三种锦鸡儿的分布式样及其生态适应   总被引:8,自引:0,他引:8  
赵一之 《生态学报》2005,25(12):3411-3414
确定了小叶锦鸡儿、中间锦鸡儿和柠条锦鸡儿3种植物的分布式样:小叶锦鸡儿为蒙古高原东部-F松辽平原西部-华北山地分布种,中间锦鸡儿为东戈壁-鄂尔多斯高原-黄土高原北部分布种,柠条锦鸡儿为南阿拉善-西鄂尔多斯分布种。小叶锦鸡儿适应分布于蒙古高原典型草原带和森林草原带以及华北山地落叶阔叶林带,在草原带高平原上可形成灌丛化草原的景观,在草原带的沙地上可形成以小叶锦鸡儿为建群种的沙地灌丛植被;中间锦鸡儿适应分布于蒙古高原的荒漠化草原及草原化荒漠带、鄂尔多斯高原的典型草原和荒漠化草原带的沙地及梁地上、黄土高原北部的黄土丘坡上,常形成以中间锦鸡儿为建群种的沙地灌丛植被;柠条锦鸡儿则适应分布于草原化荒漠和典型荒漠带的固定和半固定沙地上。近缘的3种锦鸡儿的地带性分布从东至西或从北向南形成明显的有规律的地理替代分布格局。  相似文献   

20.
中国海洋浮游端足类的物种多样性   总被引:5,自引:2,他引:3  
中国海域已发现浮游端足类122种,呈现从北部往南部海区、从近海往外海区种数逐渐增加,且暖水性也逐渐增强的分布特征。渤海、黄海北部和西南部的浮游端足类同属暖温带分布,黄海东南部和东海西北部为暖温带分布和热带分布的过渡带,东海东部和东海西南部以及台湾海峡、南海均属热带分布,其中东海东部和南海中、南部热带大洋分布的特征显著。  相似文献   

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