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1.
Two new species and one nataral hydrid close to Dryopteris chrysocoma (Christ) C. Chr. are found by means of cytological study, which shows that D. chrysocoma circumscribed in the past is not a single diploid in its range, but consists of several cytotypes. D. para-chrysocoma is a sexual diploid with narrowly lanceolate laminae that are almost glandless. The scales on the rachis and pinna rachis are pale brown, longer in length (4-7 mm) and denser. Indusium lacks glands too. The ultimate segments are narrower and separated by arrow spaces. These characters distinguish it from D. chrysocoma. D. zinongii is a sexual tetraploid. It is recognised by its ovate laminae, sparse, small and dark brown scales on the rachis and pinna rachis (1-2mm in length), broad segments closely adjacent one another and membranous indusia. D. × daliensis is shown to be an apomictic triploid which has rather irregular meiosis. There are some free chromosomes at the first metaphase, some lagging chromosomes and bridges at the first anaphase and some micronuclei in young spores. Some unpaired univalents can even be seen at diplotene. Approximately 14 univalents, 14 bivalents and 27 trivalents were observed at late diakinesis. Although a large number of SMCs were counted, a definite chromosome number has so far proved impossible to be obtained. This is possibly caused by variable pairing of the three genomes and different trivalent numbers formed in each SMC. As a result, generally less than 64 abortive spores are formed in each sporangium, but the sporangium with 32 spores could also be found rarely. All these show that this hybrid may be derived from the cross between a diploid and a tetraploid which have homoeologous genomes. D. × daliensis is morphologically intermediate between D. zinongii and D. paraChrysocoma. in respect to characters such as ovate-lanceolate laminae, brown rachis scales with a dark central stripe, 2-3 mm in length, and abortive spores in unequal size and different shapes etc. In addition, they are often found growing together in Cang Shan, Yunnan. It is therefore reasonable to consider that the latter two are probably the parents of the former. These new cytotypes show the presence of Dryopteris chry-socoma complex which is generally characterized by shell-shaped indusia and glandular fronds. Accoding to the morphology, D. woodsiisora Hayata, D. tenuissima Tagawa, D. alpicola Ching et Z. R. Wang, D. fangii Ching, Fraser-Jenkins et Z. R. Wang and D. pseudochrysocoma Ching etc. should be the members of this complex. In order to clarify the relationships between all the members of D. chrysocoma complex, a great deal of further cytogenetic study, including artificial hybridization and analysis of meiosis in both wild and synthesized hybrids, is required. The author is grateful to Prof. R. C. Ching and Mr. C. R. Fraser-Jenkins of the British Museum (Natural History) for their kind and helpful suggestion, and thank Mr. Q. Xia and Mr. Y. L. Ma for their help in the field work.  相似文献   

2.
The Dryopteris varia species complex belongs to D. subg. Erythrovariae sect. Variae and includes eight closely related, controversial species. In Korea, six species belong to the complex; D. varia s. str., Dryopteris pacifica, Dryopteris sacrosancta, Dryopteris bissetiana, Dryopteris saxifraga, and Dryopteris saxifragivaria. The morphology of these species is highly variable due to the frequent occurrence of agamospory, hybridization, and/or polyploidization. We analyzed sequences of the nDNA pgiC and cpDNA rbcL, trnL–trnF IGS and atpF–atpH IGS regions from all six of these species to elucidate their relationships and origins, and to investigate the parentage of the putative hybrid taxon, D. saxifragivaria. Fourteen nDNA pgiC haplotypes and five cpDNA haplotypes were obtained from accessions of the D. varia complex in Korea. In particular, all accessions examined appear to have multiple pgiC haplotypes. Maximum parsimony and Bayesian inference analyses of the nDNA and cpDNA sequence data show that the agamosporous triploids D. sacrosancta and D. pacifica are of allopolyploid origin involving interspecific hybridization. The results also indicate that agamosporous triploid individuals of D. saxifragivaria in Korea were derived from hybridization between sexual diploid individuals of D. saxifraga (maternal) and agamosporous diploid individuals of D. bissetiana (paternal). In addition, our results strongly suggest that the agamosporous triploid D. varia s. str. is probably of autopolyploid origin, and cytoplasmic gene flow has occurred from D. sacrosancta to Dryopteris chinensis of D. subg. Dryopteris.  相似文献   

3.
Six new species of Pteridophyta from Costa Rica are described: Dryopteris flaccisquama A. Rojas, Hypolepis lellingeri A. Rojas, H. moraniana A. Rojas, Melpomene alan-smithii A. Rojas, Selaginella osa?nsis A. Rojas and Terpsichore esquiveliana A. Rojas. Blechnum stoloniferum (Mett. ex E. Fourn.) C. Chr. and Trichomanes micayense Hieron. are new records for the country. Only D. flaccisquama and M. alan-smithii are present outside Costa Rica.  相似文献   

4.
安徽祁门地区蕨类植物区系研究   总被引:4,自引:0,他引:4  
安徽祁门地区蕨类植物共有107种(包括变种、变型),隶属于28科56属,其中发现安徽地理分布新记录种1个,即丝带蕨(Drymotaenium miyoshianum)。该区的蕨类植物优势科为鳞毛蕨科(Dryopte ridaceae)、水龙骨科(Polypodiaceae)和蹄盖蕨科(Athyriaceae);优势属为鳞毛蕨属(Dryopteris)、卷柏属(Selaginella)和复叶耳蕨属(Arachniodes)。属的地理成分以泛热带为主,亚热带和温带分布次之;种的地理分布则以中国-日本分布和中国特有分布为主。祁门蕨类植物区系在区系区划上应属于典型的华东地区。该区的蕨类植物生态类型以土生为主。种的相似性分析和属的聚类分析表明:该区系与三清山和天童山的关系密切,而与白石砬子等关系疏远。  相似文献   

5.
贵州灵芝属的种类及一新种   总被引:1,自引:0,他引:1  
本文报道了采自贵州境内的灵芝属真菌26种,其中一新种即:高盘灵芝Ganoderma cupulatiprocerum X.L.Wu et X.Q.Zhang,所有标本分别保存于中国科学院微生物研究所真菌标本室(HMAS)和海南省农业科学院。  相似文献   

6.
To investigate the origin of the triploid agamosporous speciesD. yakusilvicola, an electrophoretic analysis was made for five enzymes of theD. sparsa complex.Dryopteris yakusilvicola showed a monomorphic banding pattern for the five enzymes and was heterozygous in all six gene loci coding them. Comparison of enzyme banding patterns suggests that the genome ofD. yakusilvicola was derived through hybridization betweenD. sabaei and either a sexual tetraploid or an agamosporous triploid ofD. sparsa. Cytological evidence (Darnaediet al., 1989) supports the idea that of the two types ofD. sparsa the sexual tetraploid is a parent. The monomorphic pattern implies thatD. yakusilvicola originated from a single hybrid between the parental species, and that it is a neo-endemic of Yakushima Island.  相似文献   

7.
Rhizome and foliar anatomy of the Mexican Dryopteris Adans. species were studied and compared with other Dryopteridaceae and other fern families to identify anatomical features with diagnostic value. The anatomy of rhizome, stipe, and blade is similar in species of the Dryopteris patula complex. The cells with un-lignified, thickened wall, with cap or U-shape around the meristeles belong to the collenchyma, in contrast with other fern families. Dryopteris wallichiana (Spreng.) Hyl. is anatomically distinguished from the other studied species by having more layers of sclerenchyma and meristeles on the stipe, and by the lack of sclereid nests on the rhizome. Dryopteris rossii C. Chr. and D. maxonii Underw. & C. Chr. are characterized by the presence of crystals on the periphery of rhizome nests. D. maxonni and D. wallichiana lack blade glands.  相似文献   

8.
9.
Three new species of Dryopteris, D. cicatricata J.P. Roux and D. caperata J.P. Roux from São Tomé and D. aurantiaca J.P. Roux from Annobón are described. All three taxa appear to be local endemics. A key to the Dryopteris species occurring on the islands in the Gulf of Guinea is provided.  相似文献   

10.
BACKGROUND AND AIMS: Although allopolyploidy is a prevalent speciation mechanism in plants, its adaptive consequences are poorly understood. In addition, the effects of allopolyploidy per se (i.e. hybridization and chromosome doubling) can be confounded with those of subsequent evolutionary divergence between allopolyploids and related diploids. This report assesses whether fern species with the same ploidy level or the same altitudinal distribution have similar germination responses to temperature. The effects of polyploidy on spore abortion and spore size are also investigated, since both traits may have adaptive consequences. METHODS: Three allotetraploid (Dryopteris corleyi, D. filix-mas and D. guanchica) and three related diploid taxa (D. aemula, D. affinis ssp. affinis and D. oreades) were studied. Spores were collected from 24 populations in northern Spain. Four spore traits were determined: abortion percentage, size, germination time and germination percentage. Six incubation temperatures were tested: 8, 15, 20, 25 and 32 degrees C, and alternating 8/15 degrees C. KEY RESULTS: Allotetraploids had bigger spores than diploid progenitors, whereas spore abortion percentages were generally similar. Germination times decreased with increasing temperatures in a wide range of temperatures (8-25 degrees C), although final germination percentages were similar among species irrespective of their ploidy level. Only at low temperature (8 degrees C) did two allotetraploid species reach higher germination percentages than diploid parents. Allotetraploids showed faster germination rates, which would probably give them a competitive advantage over diploid parents. Germination behaviour was not correlated with altitudinal distribution of species. CONCLUSIONS: The results of this study suggest that (i) relative fitness of allopolyploids at sporogenesis does not differ from that of diploid parents and (ii) neither does allopolyploidization involve a change in the success of spore germination.  相似文献   

11.
福建卷柏属植物的物种多样性述评   总被引:3,自引:0,他引:3  
卷柏属Selaginella Beauv.是一个在分类上较困难的类群,种类多,形态变化大。全世界有卷柏属植物750种以上,可以分为5个亚属。2002年10月我们对武夷山脉及周边地区的卷柏种类进行了调查,采集的标本存放于新加坡国立大学标本馆(SINU)和厦门大学标本馆(AU)。此外,我们还认真观察了来自福建师范大学标本馆(FNU)和AU的卷柏标本。结果表明,在福建,卷柏有18种1变种。其中,缘毛卷柏S. ciliaris、白毛卷柏S. albociliata和布朗卷柏S. braunii是福建分布的3个新记录。  相似文献   

12.
湖北鳞毛蕨属植物分布新记录   总被引:3,自引:1,他引:2  
报道了湖北鳞毛蕨属8个新记录种,所引证的标本。全部收藏于中国科学院武汉植物研究所标本馆(HIB)。  相似文献   

13.
云南泉蝇属三新种(双翅目:花蝇科)   总被引:2,自引:0,他引:2  
薛万琦 《昆虫学报》2003,46(1):80-84
本文记述采自云南省泉蝇属3新种。1. 分布于云南省泸水片马的尖阳泉种蝇Pegomya acisophalla sp. Nov., 该种近似于四川产的黄前基泉蝇Pegomya flaviprecoxa Li et Deng, 1983, 但新种雄额宽于前单眼,侧颜等于触角宽,最长芒毛短于芒基粗;中足和后足基节黄色,后胫前背鬃3;第五腹板突立;阳茎端阳体和侧阳体等长,侧尾叶端部较宽大,表面有皱纹。2. 分布于云南泸水片马的环阳泉蝇Pegomya cricophalla sp. Nov., 该种近似毛笋泉蝇Pegomya phyllostachys Fan, 1964, 但新种雄尾器特殊,侧阳体呈环状,前阳基侧突单纯,后阳基侧突具小分支,第五腹板侧叶除基部具赘叶外,在端部具骨化的赘叶,其边缘具小齿。3. 分布于云南泸水片马的葫叶泉蝇Pegomy lageniforceps sp. Nov.,该种近似黄前基泉蝇Pegomya flaviprecoxa Li et Deng, 1983, 但新种雄性触角淡棕色,侧颜约等于触角宽,颊高为侧颜宽的2倍;小盾端部带褐色;翅脉淡棕色;中足后足基节黄色,中胫后鬃3,后股中部具2~3根后腹鬃,后胫前背鬃3;雄性尾器不同, 后阳基侧突前枝的端部为菱形,侧尾叶端部后面观略宽大,肛尾叶近葫形, 阳体的端阳体较短而细。模式标本保存于沈阳师范大学昆虫研究所。  相似文献   

14.
Apogamous fern species are often difficult to distinguish from related species because of their continuous morphological variations. To clarify the genetic relationships among the members of the Dryopteris varia complex, we analyzed the nucleotide sequences of the plastid gene rbcL and the nuclear gene PgiC. We also analyzed the diploid sexual species D. caudipinna and D. chinensis, which have not been included in the complex, but were recently shown to be closely related to the complex in a molecular phylogenetic study. The PgiC sequences of the diploid sexual species, D. varia, D. saxifraga, D. sp. ‘protobissetiana’ (undescribed diploid sexual species), D. caudipinna, and D. chinensis, were well differentiated and hence designated A, B, C, D, and E, respectively. Thus, the PgiC constitution of apogamous species in the complex was as follows: D. bissetiana, B + C; D. kobayashii, B + C + E); D. pacifica, A + C, A + B + C, or A + C + D; D. sacrosancta, A + C + E; and D. saxifragivaria, B + C. These results suggest that these apogamous species are formed by hybridizations of species including not only the three diploid sexual species of the D. varia complex (A, B, and C) but also the two diploid sexual species D. caudipinna (D) and D. chinensis (E), which do not belong to the complex.  相似文献   

15.
中国云南西部地衣区系(英文)   总被引:2,自引:0,他引:2  
对中国云南西部高山地区的大型地衣进行了调查。采集地衣标本400余份,鉴定为46属86种,其中40种在朝鲜半岛有报道。所有采集的标本现保藏于顺天大学韩国地衣研究所和中国科学院昆明植物研究所隐花植物标本馆。  相似文献   

16.
Dysanabatium hainanense Peng & Li, sp. n. (Hainan: Wuzhi Shan, Diaoluo Shan) is described and illustrated. Additional records of D. jacobsoni Bernhauer, 1915 are reported. The habitus, the sexual characters, and the distribution of this enormously variable species are illustrated.  相似文献   

17.
本文报道了海南省粉褶蕈属[Entoloma(Fr.)Kumm.]的31个种,其中17个为新记录种。并附分种检索表,表中含6个新种。 所有标本保藏于广东省微生物研究所真菌标本室。  相似文献   

18.
本文报道了海南省粉褶蕈属[Entoloma(Fr.)Kumm.]的31个种,其中17个为新记录种。并附分种检索表,表中含6个新种。 所有标本保藏于广东省微生物研究所真菌标本室。  相似文献   

19.
Spore germination of five globally threatened fern species [Culcita macrocarpa C. Presl, Dryopteris aemula (Aiton) O. Kuntze, D. corleyi Fraser-Jenkins, D. guanchica Gibby and Jermy and Woodwardia radicans (L.) Sm.] was determined after 1, 6 or 12 months of storage in glass vials (dry storage) or on agar (wet storage) at -20, 5 or 20 degrees C. In all species, storage technique, storage temperature and the technique-temperature interaction all had a significant effect on germination percentage. In most cases, the germination percentage was best maintained by wet storage at 5 or 20 degrees C. In the case of the hygrophilous species C. macrocarpa and W. radicans, 6 or 12 months' dry storage killed most spores. Only Woodwardia radicans germinated in the dark during wet storage at 20 degrees C. Wet storage at 5 degrees C prevented dark germination, and reduced bacterial and fungal contamination. Wet storage at -20 degrees C killed all or most spores in all species. In the three Dryopteris species, the differences among the storage conditions tested were smaller than in C. macrocarpa and W. radicans, and the decline in spore viability during storage was less marked, with high germination percentages being observed after 12 months of dry storage at all three temperatures. Dry storage, which has lower preparation time and space requirements than wet storage, was generally more effective at the lower temperatures (-20 or 5 degrees C).  相似文献   

20.
Abstract The present paper deals with three new species of genus Delia from Gansu province, China, namely Delia ancylosurstyla sp. nov., D. apicijoralis sp. nov. and D. longiarista sp. nov. All the type specimens are deposited in the Institute of Zoology, Chinese Academy of Sciences, Beijing, China.  相似文献   

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