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1.
The Hordeum parodii group contains three species, viz. H. parodii Covas (6x), H. tetraploidum Covas (4x), and H. fuegianum Bothmer, Jacobsen, et Jørgensen, sp. nov. (4x). The former two species mainly occur in C and S Argentina, while H. fuegianum is native to Tierra del Fuego. All three species are probably of alloploid origin. Morphological, isoenzyme variation and cytogenetic data are presented.  相似文献   

2.
The genus Hemitragus includes three species of tahr distributed in distant geographical areas: the Himalayan tahr, H. jemlahicus, occupies the southern flanks of the Himalaya Mountains; the Nilgiri tahr, H. hylocrius, is endemic to southern India; and the Arabian tahr, H. jayakari, is unique to the mountains of south-east Arabia. All previous investigations were based on morphology, and these three species together have never been included in a molecular phylogenetic study. In this study, we constructed a molecular phylogeny of the tribe Caprini sensu lato to determine the taxonomic status of the three species of tahr. Phylogenetic analyses were carried out on a matrix including most extant species currently described in the tribe Caprini sensu lato, and 3165 nucleotide characters, coming from four different markers, i.e., an intron of the nuclear gene coding for the protein kinase C iota, and three mitochondrial genes (subunit II of the cytochrome c oxidase, cytochrome b, and 12S rRNA). The results show that the genus Hemitragus is polyphyletic, as H. jemlahicus is associated with Capra (goats), H. hylocrius is the sister-group of Ovis (sheep), and H. jayakari is allied with Ammotragus lervia (aoudad). In the light of these unexpected results, we revaluate the validity of the morphological characters originally used for defining the genus Hemitragus. At least, we propose a new taxonomy, where the three species of tahr are ranged into three monospecific genera: the genus Hemitragus is restricted to the Himalayan tahr, and two new genera are created: Arabitragus for the Arabian tahr and Nilgiritragus for the Nilgiri tahr.  相似文献   

3.
The genus Helcogrammoides comprises three species of small, cryptic shorefishes, H. antarcticus, H. chilensis, and H. cunninghami. All three species inhabit shallow water along exposed rocky coasts. Specimens reported herein extend the known distributions of H. chilensis and H. cunninghami to the vicinity of Lima, Peru, approximately 1600 km north of their previously reported northernmost records in Chile. Helcogrammoides chilensis and H. cunninghami occur sympatrically over most of their ranges in Peru and Chile and are frequently taken together in the same field collections. Lectotypes are designated for H. chilensis and H. cunninghami. Diagnoses and an identification key are provided for the species.  相似文献   

4.
Paul A. Fryxell 《Brittonia》1969,21(4):359-396
The genusHampea Schlecht. is included in the Malvaceae, tribe Gossypieae, rather than in the Bombacaceae where it was originally placed. Discussion includes the morphology, geography (central Mexico to western Colombia), reproductive cycle, utilization and vernacular names, and cytology (n = 13) of the genus. Three species have perfect flowers; the remainder are dioecious. The 16 species (and one variety) that are accepted are divided into three sections, one of which is further subdivided into three series. The following taxa are described as new:H. nutricia, H. mexicana, H. sphaerocarpa, andH. appendiculata var.longicalyx.  相似文献   

5.
海南锈革菌属研究(英文)   总被引:1,自引:0,他引:1  
何双辉 《菌物学报》2010,29(6):819-823
对海南省的锈革菌属Hymenochaete进行了初步研究,共发现了该属12个种。其中异常锈革菌H.anomala和薄锈革菌H.minuscula为中国新记录种,竹生锈革菌H.muroiana为大陆新记录种。异常锈革菌具有带结晶的菌丝和囊状体;薄锈革菌子实体薄,黄褐色;竹生锈革菌有"T"形刚毛,生于竹子上。文中对3个新记录种进行了描述,并给出了全部12个种的检索表。  相似文献   

6.
记述了我国圆点小卷蛾属EudemisHbner的种类,共4种,其中包括1新种:郑氏圆点小卷蛾E.zhengi sp.nov.。提供了分种检索表、新种的形态特征图和生殖器图。模式标本保存在南开大学昆虫标本室。郑氏圆点小卷蛾,新种Eudemis zhengi sp.nov.(图1~2)新种与杨梅圆点小卷蛾E.gyrotis(Meyrick)相似,但可通过下列特征区别:雄性外生殖器之颚形突中部的突起宽短,同时侧缘还具尖角状突起并被细齿,抱器瓣仅在抱器腹近基部具1簇刺丛;后者颚形突中部的突起长指状,侧缘无突起,抱器瓣腹缘具3簇刺丛,分别位于抱器腹基部和端部及抱器端基部2/5处。正模♂,云南勐腊补蚌(21°29′N,101°33′E;海拔650m),25Aug.2005,任应党采;玻片号YHL05159。词源:新种种名以郑哲民教授的姓氏命名,以示对郑先生在我国昆虫系统学研究领域做出显著贡献的敬意。  相似文献   

7.
8.
Eight populations of Hemerocallis thunbergii, H. middendorffii , and H. exaltata from Japan were analyzed by starch gel electrophoresis to measure genetic variation at ten allozyme loci. The former two species are widely distributed in eastern Asia, whereas H. exaltata is restricted to the Tobishima and Sado Islands in western Japan. Populations of the three species maintain high levels of allozyme variation: mean expected heterozygosities were 0.288, 0.209, and 0.169, respectively. The UPGMA phenogram obtained from Nei's genetic distance values indicated that H. exaltata is allozymically the most distinct species, whereas populations of H. thunbergii and H. middendorffii are closely related. However, based on gross morphology H. exaltata and H. middendorffii are closely related. This discrepancy and the observed high levels of allozyme variation within populations of the three Hemerocallis species in Japan may in part be due to genetic change among populations of the two Japanese archipelago species.  相似文献   

9.
Three Asian species of the genus Hediste (Nereididae, Polychaeta, Annelida), including two new species, are reviewed. Hediste japonica (Izuka, 1908) was redescribed based on recently discovered type material and on additional specimens newly collected from the Ariake Sea in Japan and the west coast of Korea. Two new species, H .  diadroma and H. atoka , were described based on specimens collected from Japan. These three species are morphologically similar, but distinguishable by some differences in parapodial and chaetal morphology, at least at the sexually mature stage. The presence of homogomph falcigers and the absence of heterogomph spinigers are unique characteristics of H. japonica among this genus. Inconspicuous epitokous metamorphosis occurred as a slight enlargement of the eyes and parapodial ligules in mature adults of H. diadroma sp. nov. and H. japonica in combination with their reproductive swarming and pelagic larval development. The epitoke-specific sesquigomph spinigers were added in mature adults of H. diadroma sp. nov., while the number of ordinary homogomph spinigers increased in some adults of H. japonica. Epitokous metamorphosis in the Hediste species was compared with that in other nereidid genera. No epitokous metamorphosis was observed in H. atoka sp. nov., corresponding to its reproduction without swarming and to its development without a planktonic larval stage. Significant differences in paragnath numbers in the maxillary ring of the proboscis were found among the three species, suggesting different feeding habits. In Japan, the present distribution of H. japonica is restricted to muddy tidal flats in the inner part of the Ariake Sea, probably due to recent human impact, while the other two species are widespread.  © 2003 The Linnean Society of London. Zoological Journal of the Linnean Society, 2003, 137, 403−445  相似文献   

10.
萱草属中国特有种的细胞分类研究   总被引:6,自引:1,他引:5  
对萱草属3个中国特有种,折叶萱草、西南萱草和多花萱草间的亲缘关系,不同学者有不同观点。本文试图从核型特征阐明三者的亲缘关系。折叶萱草、西南萱草和多花萱草的核型公式分别为:2n=12m+8sm+2T;2n=8m+12sm+2T和2n=12m+4sm+4st+2T。核型不对称性依次加大;三者均在T型(第11号)染色体着丝点端具有微小随体。三者染色体组分之间的欧氏距离:折叶萱草与西南萱草为0.2728;折叶萱草与多花萱草为0.4501;西南萱草与多花萱草为0.5741。以上资料表明,折叶萱草与西南萱草更为近缘,而多花萱草比前二者进化。  相似文献   

11.
Two new species of hyalellid amphipods, Hyalella crawfordi and H. gauthieri, are described from Lake Titicaca; H. echinus (Faxon, 1876) is redescribed. The H. echinus group of species is newly proposed for these three species, and a group diagnosis is provided. A key to the three species in the group is provided Full article published online at http://www.senckenberg.de/odes/06-10.htm.  相似文献   

12.
The Southern hemisphere aorid amphipod genera Haplocheira Haswell and Kuphocheira Barnard are revised and Anonychocheirus gen. nov. is described from Antarctica. A key is provided to distinguish the three genera and six species currently known. Material attributed to H. barbimana (Thomson, 1879) from Antarctica, South Georgia, Australia, lies de Kerguelen, New Zealand and Auckland Is. has been re-examined. The Antarctic material proves to be separate on the basis of antennal peduncle proportions, shape of lateral cephalic angle and shape and setation of peraeopod bases. Stebbing's species plumosa is re-established for this entity. Haplocheira robusta Barnard is synonymized with H. barbimana and three subspecies are described, viz. H.b. barbimana (Thomson) from New Zealand and Auckland Is., H.b. typica Haswell from Australia and lies de Kerguelen (shallow water) and H.b. robusta Barnard from Magellanic South America and the Falkland islands. Haplocheira balssi Schellenberg remains a separate species. Kuphocheira setimanus Barnard is re-assessed and K. emancipata sp. nov. described from Antarctica. The new genus Anonychocheirus is presently known only from the type species A. richardsoni sp. nov. described herein.  相似文献   

13.
Summary Two new species of the genus Heterokrohnia, H. longidentata and H. fragilis, are described and compared with the other three known Heterokrohnia species, H. mirabilis Ritter-Záhony 1911; H. bathybia Marumo and Kitou 1966 and H. involucrum Dawson 1968. The species have been found at great depths (1,000 m–2,000 m) near Elephant Island, north of the Antarctic Peninsula.  相似文献   

14.
The present paper includes a morphological, ecological and biological updating of the three gorgonian associated species of Haplosyllis (Polychaeta, Syllidae) known to date: H. chamaeleon (symbiont with Paramuricea clavata in the Mediterranean), H. anthogorgicola (symbiont with Anthogorgia bocki in the Japanese seas) and H. villogorgicola , a new species living symbiotically with Villogorgia bebrycoides which is only known from Tenerife (Canary Islands, Eastern Central Atlantic). The new species is described on the basis of ecological, morphological, morphometric and statistical analysis of relevant characteristics. Each host colony harboured about 15 pale-yellowish worms, whose cryptic colouration mimicked that of the host. They occurred either on the host branches or partly hidden inside cavities formed by the fusion of two branches. The new species is characterized by the presence of simple chaetae with clearly bidentate tips all along the body, the presence of gland pore aggregates distributed in two lateral rows and two ventral patches on each palp and the absence of ciliary tufts on the pharyngeal papillae. H. villogorgicola sp. nov. is closely related to H. chamaeleon . Thus, it is compared with two populations of this species collected in the north-west and south-west Mediterranean. Stolons of H. chamaeleon are re-described as tetracerous and a peculiar posterior end regeneration process occurring in adult worms during the stolon formation is described. H. anthogorgicola is also re-described, with particular emphasis on its appendage and chaetal arrangements. The main features of the three associations are discussed in light of the current knowledge on symbiotic polychaetes, particularly cnidarian-associated syllids.  © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 77 , 455–477.  相似文献   

15.
The nocturnal-flowering group of Hemerocallis was treated as including three separate species, H.lilioasphodelus,H.citrina and H.minor in the Florae Reipublicae Popularis Sinicae Vol.14(1980).However it is difficult to distinguish them from one another by a single feature,such as the flower number,length of perianth tube,diameter of tuberous roots,for they are strongly overlapping.In the present paper,numerical analysis was made of nine morphological characters and karyotype divergences which are of taxonomic significance as shown in the study of H. fulva and its two varieties (Xiong and Chen,1992),based on dry and living materials from China.In addition,geographical distribution pattern of the three taxa studied shows that they seem to be different geographical races or allopatric ecotypes in a topocline,since they inhabit a climate gradient from warm and moist to cold and drought condition.As a result,the present authors tend to consider it more reasonable to treat them as a single species,H.lilioasphodelus,with three subspecies,that is, H.lilioasphodelus ssp.lilioasphodelus,H.lilioasphodelus ssp. citrina (stat.nov) and H.lilioasphodelus ssp.minor(stat.nov.)  相似文献   

16.
Cyst and root-knot nematodes show high levels of gross morphological similarity. This presents difficulties for the study of their ecology in natural ecosystems. In this study, cyst and root-knot nematode species, as well as some ectoparasitic nematode species, were identified using the second internal transcribed spacer (ITS2) sequence variation detected by polymerase chain reaction-single-strand conformational polymorphism (PCR-SSCP). The ITS2 region was sufficiently variable within the taxa investigated to allow species to be separated on the basis of minor sequence variation. The PCR primers used in this study were effective for 12 species with three genera within the Heteroderinae (Globodera pallida, G. rostochiensis, Heterodera arenaria/avenae, H. ciceri, H. daverti, H. hordecalis, H. mani, H. schachtii, H. trifolii, Meloidogyne ardenensis, M. duytsi and M. maritima). However, pathotypes of Globodera pallida and G. rostochiensis could not be distinguished. The method was tested at two coastal dune locations in The Netherlands (one in the lime-poor dunes of the north and one in calcareous dunes of the south) to determine the population structure of cyst nematodes. At each site, cyst nematodes were associated with three plant species: two plant species on the foredune (Elymus farctus and Ammophila arenaria) and one plant species occurring further inland (Calamagrostis epigejos). Two species of cyst nematodes, H. arenaria and H. hordecalis, were found. H. arenaria associated with vigorous A. arenaria and H. hordecalis in association with degenerating A. arenaria and C. epigejos. The field survey demonstrated that in coastal dunes abiotic factors may be the important affecting the distribution of cyst nematodes.  相似文献   

17.
Abstract This paper deals with Chinese species of Hemiptarsenus Westwood, 1833. Totally five species are found in China. Among them, H. unguicellus (Zetterstedt), H. ornatus (Nees) and H. varicornis (Gi‐rault) were previously recorded, H. zilahisebessi Erdös is newly recorded in China and H. strigiscuta sp. n. is described as new. A tentative key to known species is given, and other three external species, H. fulvicollis Westwood, H. wailesellae Nowicky and H. waterhousii Westwood, are included in the key for comparison. The type specimen is deposited in the Zoological Museum, Institute of Zoology, Chinese Academy of Sciences.  相似文献   

18.
【目的】沟胸步甲属Holcoderus属于鞘翅目(Coleoptera)步甲科(Carabidae)壶步甲族(Lebiini)。本研究旨在对该属在中国分布的各个种进行分类厘定。【方法】基于中国科学院动物研究所的馆藏标本以及欧洲多家博物馆的模式标本,采用形态比较学方法开展研究。【结果】共发现中国沟胸步甲属5种,其中包括新种1种(双毛沟胸步甲H. bisetus sp. n.,模式产地:云南西双版纳),中国新纪录种3种(雅沟胸步甲H. gracilis、绿沟胸步甲H. smaragdinus和红腿沟胸步甲H. aeripennis)。提供了中国所有种类的形态描述及特征图,并编制了分种检索表。【结论】至此,我国所分布的沟胸步甲属物种从此前记录的1种增加至5种。  相似文献   

19.
We present an analysis of isozyme variability in natural populations of the plant species Hippocrepis valentina (Leguminosae), which is endemic to the eastern Mediterranean coast of Spain and currently has endangered species status. Our results, obtained by starch-gel electrophoresis of 15 loci, show normal levels of variability for species with similar biology. The comparison with the patterns of genetic variability of two closely related species, H. balearica and H. grosii, confirms the taxonomic status of H. valentina as a proper species, independent of H. balearica, as previously suggested. The analysis of population subdivision shows that substantial variation among populations is present, and a hierarchical analysis demonstrates that when zones are defined according to their geographic location, a higher differentiation among populations within zones than among zones is found. Indirect estimates of gene flow indicate that levels of migration per generation are relatively low, except for a group composed of four populations, three of which are in close proximity. For the remaining populations, there is evidence of substantial differentiation. These results have implications for the design of a conservation strategy for this species.  相似文献   

20.
Intraspecific variability in three closely related chigger mite species of the genus Hirsutiella Schluger et Vysotzkaya, 1970, H. steineri (Kepka, 1966), H. llogorensis (Daniel, 1960), and H. alpina Stekolnikov, 2001 has been studied based on materials collected in Caucasus and Turkey. It is established that both H. steineri and H. llogorensis include Western Caucasian and Asian forms, the first one being larger than the second one. Western Caucasian samples of H. steineri are also split into large and small forms. The large form inhabits screes with larvae occurring mainly on snow voles, and the small form inhabits meadows and forests with larvae parasitizing snow voles as well as mice of the genus Apodemus and pine voles. Asian population of H. steineri include small low-mountain form which is hard to distinguish from H. llogorensis. In the light of the new data on variability, morphological border between these two species are specified. Correlations between some characters and altitude above sea level are shown within the Western Caucasian and Asian forms of both species, and also in H. alpina. All the three species can occur together on the same individual hosts, but they have different sets of main hosts and different distribution among biotopes in the area of sympatria. The border between H. steineri and H. llogorensis in the places of sympatria can be indistinct owing to the presence of small ecological forms of H. steineri. Our results give a basis for the construction of alternative hypotheses concerning the processes of speciation in trombiculids. Chiggers species could be formed in allopatric way, on the base of such geographical forms, as Western and Asian forms of the Caucasian Hirsutiella species, but they could also be formed in sympatric way, distributing among neighbouring biotopes (e.g., screes and meadows, or screes and forests), as large and small forms of Western Caucasian H. steineri do.  相似文献   

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