共查询到20条相似文献,搜索用时 23 毫秒
1.
2.
Abstract The species of the genus Syntretus Foerster form China are revised in this paper. Five species are recognized with one species, Syntretus longitergitus sp. nov., as new to science. A key to the Chinese species fo this genus is provided. 相似文献
3.
The genus Shelfordia is discovered in China for the first time, and one new species of this genus (S. chinensis sp. nov.) is fully described and illustrated in the present paper. The type specimen is deposited in the Parasitic Hymenoptera Collection, Zhejiang University, Hangzhou, China. 相似文献
4.
Steven J. Wolf 《American journal of botany》1980,67(3):300-308
A total of 134 chromosome counts representing 21 taxa of the genus Arnica are presented. Counts are published here for the first time for A. lonchophylla (n = 38) and A. nevadensis (n = 38). Ten previously unreported counts representing 9 taxa are also presented. The basic chromosome number of the genus is x = 19. With respect to chromosome number, the genus exhibits maximum diversity in the Rocky Mountains of Colorado and Wyoming. Arnica angustifolia, A. cordifolia and A. mollis are recognized as mature polyploid complexes, containing several wide ranging polyploid races and only a few highly restricted or scattered diploid races. Within the genus in general, diploids tend to be restricted to unglaciated areas while polyploids are much wider ranging, particularly in unglaciated areas. 相似文献
5.
6.
A collection of anatomically preserved conifer cones from the Early Cretaceous of Virginia contains two new species of the extinct pinaceous genus Pityostrobus. Superficially, the fossil cones resemble those of modern species of Picea. However, the fossils reveal such a peculiar mixture of anatomical features that they cannot be assigned to any extant genus of the Pinaceae. One of the new species, Pityostrobus hueberi, is most comparable with Pityostrobus corneti Alvin from the Early Cretaceous of Belgium. Pityostrobus virginiana, the other new species, differs from all other members of the genus in only slight—but nonetheless significant—attributes. Pityostrobus hueberi and P. virginiana are the first species of this genus to be reported from Early Cretaceous sediments of the North American Atlantic Coastal Plain. As such, they increase our knowledge of the structural variation exhibited by ancient members of the Pinaceae. 相似文献
7.
The position of the rare and monotypic genus Karimbolea is clarified. Its tribal affinities are examined using mainly floral characters; the former tentative placement in the tribe Asclepiadeae (Asclepiadaceae) is confirmed. Characters of vegetative and floral morphology are used to determine the position of the genus within the tribe Asclepiadeae. Sarcostemma is identified as the most likely sister taxon of Karimbolea. Triterpenoid data obtained from gas-liquid chromatographic analysis of latex are used to test this hypothesis. This paper forms the first study within the Asclepiadaceae using two independent data sets to clarify the position of a taxon of uncertain affinities. 相似文献
8.
Irving W. Knobloch William Tai Thamby Ninan Adangappuram 《American journal of botany》1975,62(6):649-654
Confirmatory, corrective and new chromosome counts are listed for species in the genus Cheilanthes, and a new chromosome count is given for a member of the genus Aspidotis. An analysis of five collections of C. castanea revealed no significant morphological differences despite the different chromosome numbers. The ploidy level of all known species in genera of the Sinopteridaceae is summarized, revealing directions in which future research might proceed to complete our cytological knowledge of this family. 相似文献
9.
A comparative study was made of the gross morphology, fine venation and cuticular features of Leitneria fioridana Chapman, the single living representative of the order Leitneriales and Leitneria eocenica (Berry) Brown, presumbaly a related fossil species. In addition to the type material, newly collected fossil specimens were investigated from clay pits in the Middle Eocene, Claiborne Formation, of western Tennessee and Kentucky. Foliate stipules attached to the petioles of several specimens suggest the assignment of this fossil leaf type to the genus Leitneria is incorrect. The nature of the gross morphology, fine venation and cuticular features confirms the misidentification. Previously, various specimens of this fossil leaf type have been placed in eight species of seven genera in seven families of six angiosperm orders, none of which are correct systematically. The gross morphology, venation and cuticular characters of the fossil leaf are distributed among a few extant South American genera of arborescent Rubiaceae. The fossil is an extinct rubiaceous leaf type which cannot be placed within a single modern subfamily, tribe or genus of the family. The organ genus, Paleorubiaceophyllum is proposed for these leaves. Three varieties of a single fossil species, P. eocenicum, are recognized. One variety with epidermal cells nearly twice the size of the others may represent a polyploid population. 相似文献
10.
Gar W. Rothwell 《American journal of botany》1972,59(10):993-999
Numerous specimens of the pteridospermous pollen organs Idanothekion glandulosum and Callandrium callistophytoides are present in Middle and Upper Pennsylvanian petrifaction material, respectively. Several specimens of Idanothekion, previously known only in an isolated condition, are attached to foliage assignable to the monostelic seed fern Callistophyton. Proof of the affinities of Idanothekion allows this genus to be elevated from a form genus to an organ genus in the Callistophytaceae. The structure of the foliage and the mode of attachment of the Idanothekion specimens are like those previously described for Callandrium. Structural features of Idanothekion and Callandrium are compared, and the question of their identity is discussed. At present one basic type of pollen organ, borne on the abaxial surface of foliar pinnules, is known for members of the Callistophytaceae. 相似文献
11.
R. K. Owen 《African Journal of Aquatic Science》2013,38(1-2):148-152
Summary The ocypodid genus Paratylodiplax was described in 1974 and contains four species, three of which are endemic to southern Africa where they form an important component of the estuarine benthic fauna. However, very little is known about the biology and ecology of the genus, with discrepancies existing between the commonly quoted distributions and actual records of the species. This comment outlines the current taxonomic status of the genus and attempts to resolve the discrepancies in the distributions of the southern African species Paratylodiplax blephariskios has been recorded from the Morrumbene estuary in Mozambique to the Mngazana estuary in the eastern Cape, while the distributions of P. algoensis and P. edwardsii are given as being from the Mngazana to the Eerste estuary and Langebaan Lagoon in the western Cape respectively. 相似文献
12.
C. G. G. J. van Steenis 《American journal of botany》1969,56(7):805-807
The monotypic genus Thysanospermum Champ. ex Bth. from the Far East is reduced to the Indo-Asiatic genus Coptosapelta. It is a marked example of the insufficient attention given to testing, emending, or revising old generic concepts which in the tropics are so often taken for granted from handbooks. It is suggested that large critical regional floras are most appropriate for curing this inadequacy which hampers progress in our understanding of both taxonomical insight and geographical distribution. 相似文献
13.
WANG Xin‐hua 《Insect Science》2000,7(3):223-226
Abstract Xenochironomus tuberosus sp. nov. from southern China is here described and illustrated as male imagines. The new species is separated from other known species of this genus in having frontal tubercle, unusual stout setae on tergite VI, characteristic chaetotaxy on tergite IX and unique superior volsela. Based on the new species, an emendation to the diagnosis of the genus is given. This paper is the first record of genus Xenochironomus from China. 相似文献
14.
菌绒孢是一个小属,已描述过的种约50个,都是植物寄生菌,有的引致植物病害还较 严重.本文报告了我国产的21个种,其中1个是新种,4个是新组合和2个新记录,对18个种均有英文描述和附图,新种还附有拉丁文简介,各个种的地区分布也予以载述.但文中有分布地区而其后未附HMAS标本号码者多系据《中国真菌总汇》(1979)转录.从前人的描述和我们研究中看出,菌绒孢属的属级特征有:(1)产孢细胞合生,合轴式多点全壁芽茁产孢;(2)分生孢子梗壁上和分生孢子顶端和基脐,或仅基脐的孢痕疤明显而厚;(3)分生孢子梗主要从表生甸甸菌丝上作为侧枝或顶生,但有的种也兼有从子座上 簇生的;(4)菌丝多结集成菌丝绳或攀缘于叶毛上;(5)分生孢子链生,少数种也不链生. 这就清楚表明菌绒孢属与尾孢菌属和色链隔孢属(Phaeoramularia)少不同之处在于,尾孢 菌和色链隔孢属二者的分生孢子梗均成簇发生且无表生匍匐菌丝,与极其近似的假尾孢属(Pseudocercospora)不同之处在于,后者的分生孢子梗也着生于表生匍匐状菌丝和簇 生于子座上,但其分生孢子梗和分生孢子的孢痕疤却薄而不明显,因而易于区别开.虽然1974年von Arx在其《纯培养产孢真菌的属》一书中,曾把菌绒孢属作为枝孢 属(Cladosporium)的异名,但这一观点我们未予接受,其理由已在《中国色链隔孢曲(1982)一文中加以说明,这里未予重述.上述这21个种除3个种,即M. costaricensis, M, pawlownicola和M. vaginae我们未获得研究材料,仅据以前作者的报导转录外,其余18个种均系根据标本进行的.这些标本,含M. merremiae sp. nov.的模式标本在内,均贮藏于中国科学院微生物研究所真菌标本室. 相似文献
15.
Lindsay S. Olive 《American journal of botany》1962,49(3):297-303
Olive , L. S. (Columbia U., New York, N. Y.) The genus Protostelium . Amer. Jour. Bot. 49(3): 297–303. Illus. 1962.—Two new species of this simplest genus of the cellular slime molds are described: P. fimicola , a species with spherical spores and gelatinizing stalks occurring on dung, and P. arachispora , an elongate-spored species from dead plant material. The first has been found in North Carolina and the West Indies, while the second species has been found only once in North Carolina. Protostelium mycophaga var. major , from Connecticut, has distinctly larger spores than the original species. Further data on the distribution and development of P. mycophaga are presented. The genus is transferred to a family of its own, the Protosteliaceae . 相似文献
16.
C. W. Hesseltine 《American journal of botany》1960,47(3):225-230
Hesseltine , C. W. (Northern Utilization Research and Development Division, Peoria, Ill.) The zygosporic stage of the genus Pirella (Mucoraceae). Amer. Jour. Bot. 47(3) : 225—230. Illus. 1960.–Pirella circinans Bainier has been found to be heterothallic. The zygospores, which have never before been reported, are formed when + and – strains are mated at 15°C. on such media as tomato paste-oatmeal or potato dextrose agars. Zygospores are formed in a diffuse manner in the aerial mycelium and are similar to those found in the genus Mucor. The single species, P. circinans, is described on a synthetic medium and its synonyms are listed. It is believed to represent a genus between Mucor and the family Thamnidiaceae. 相似文献
17.
关于子囊菌亚门石耳科的属级分类问题地衣学家持有不同的观点。这些观点使属级分类出现了单属系统,二属系统,三属系统以及四属系统与五属系统。现在新二属系统,即石耳属一疱脐衣属系统已被越来越多的地衣学家和子囊菌学家所接受。但是,因为由Dodge (1968)描述的单种属拉诺属(Llanoa)的模式种与早已为人熟知的网脊石耳很相似,而近年来,这一单种属又被一些作者所接受、因此、我们不得不对该属模式种所依据的原始材料进行必要的复查。复查结果表明,拉诺属的模式种卖为网脊石耳的异名。因此,拉诺属也就成为石耳属的异名。此外,基于石耳科中三十五种地衣和五十二项特征的聚类分析结果也支持新的二属系统。 相似文献
18.
Abstract Four Chinese species of genus Bryomyia Kieffer are recorded in the present paper, among which, one species: B. puberula Li et Bu is described as new to science; two species; B. bergrothi Kieffer and B. gibbosa (Felt) are recorded for the first time from China. Key to the known Chinese species of the genus is given. Type specimen is deposited in the Department of Biology, Nankai University, Tianjin, China. 相似文献
19.
Abstract The genus Donaciolagria Pic is transferred from the subfamily Lagriinae to the subfamily Statirinae. The species Donaciolagria femoralis (brchmann) is redescribed. Two new species, D. viridimetallica sp. nov. and D. flavitibialis sp. nov. are described. A key to Chinese species of the genus is given. With 22 original pictures. 相似文献
20.
Complete cytochrome b gene sequences from all but one species of delphinid plus four outgroups were analyzed using parsimony, maximum likelihood, and neighbor-joining methods. The results indicate the need for systematic revision of the family; a provisional classification is presented and compared to previous studies. Among the suggested revisions are removal of Orcinus from the Globicephalinae, placement of Grampus within the Globicephalinae, removal of all Lagenorhynchus spp. from the Delphininae, and placement of Sousa in the Delphininae. The genus Lagenorhynchus is found to be polyphyletic. L. albirostris (type species for the genus) and L. acutus are not closely related to each other or to nominal congeners. L. acutus is therefore assigned to the genus Leucopleurus. The remaining four Lagenorhynchus species are closely related to Lissodelphis and Cephalorbynchus and are placed in the genus Sagmatias. These three genera constitute the revised Lissodelphininae. Within the Delphininae, a well-supported clade includes the two species of Delphinus, Stenella clymene, S. frontalis, S. coeruleoalba, and the aduncus form of Tursiops truncatus. Accepting the monophyly of this group renders the genera Stenella and Tursiops polyphyletic. Apart from this finding, phylogenetic resolution within the Delphininae was poor, so comprehensive taxonomic revision of this group awaits further study. 相似文献