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1.
A new Polystichum (Pteridophyta: Dryopteridaceae) hybrid, P. x saltum is described. Several micromorphological characters are anomalous in their being a summation of the character states of the progenitors rather than being intermediate or closer to one of the parent species. The putative parents of this sterile hybrid are P. transvaalen.se and P. wilsonii , both sexual tetraploids (2 n = 164). Polystichum x saltum also has a somatic chromosome number of 2 n = 164, but meiosis yields univalents and bivalents.  相似文献   

2.
阿当耳蕨 新种 图1 Polystichum adungense Ching et Fraser-Jenkins sp. nov. in sched. Species affinis P. rhomboidei Ching, sed pinnis herbaceis, utrinque paleis fibrosis dif-fert. Tota planta 12—14 cm. alta. Rhizoma erectum, paleis brunneis, lanceolatis obtectum.  相似文献   

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4.
贵州产耳蕨属(鳞毛蕨科)一新种—韭菜坪耳蕨   总被引:3,自引:0,他引:3  
骆强 《植物研究》2009,29(2):134-135
描述了贵州耳蕨属一新种,即韭菜坪耳蕨(Polystichum jiucaipingense P. S. Wang et Q. Luo)。新种与栗鳞耳蕨(P. castaneum(Clarke) Nayar et Kaur)相近,但植株较小,叶柄、叶轴上的鳞片淡棕色,孢子囊群着生于全部羽片上而不同。  相似文献   

5.
Polystichum adungense ching et Fraser-Jenkins is described as new from N. Burma and S. W. China  相似文献   

6.
报道了河南省鳞毛蕨科耳蕨属一新记录种——亮叶耳蕨(Polystichum lanceolatum Baker)。对该种进行了特征描述,并编制了河南耳蕨属植物检索表。该种近似正宇耳蕨(P.liui Ching),但羽片上侧耳状凸起不明显,边缘有7~8个具短刺头的牙状齿,孢子囊群在主脉上侧最多3个,下侧不育或偶有1个,囊群盖圆盾形,全缘等特征而不同。凭证标本存放于河南农业大学植物标本馆(HEAC)。  相似文献   

7.
陕西秦岭鳞毛蕨科的2个新记录种   总被引:4,自引:0,他引:4  
徐皓  王玛丽 《西北植物学报》2006,26(6):1250-1252
报道陕西秦岭的2个蕨类新记录种:乌柄耳蕨(Polystichum melanostipes)和密鳞鳞毛蕨(Dryopterispycnopteroides)。根据标本对两种植物的形态进行了详细描述,同时对其地理分布进行了简要说明。  相似文献   

8.
报道了四川贡嘎山地区耳蕨属5个新分类群,即阔基耳蕨,深裂耳蕨,铺散耳蕨,缺耳耳蕨,寒生耳蕨。  相似文献   

9.
Cytological observations on five Dryopteris species and four Polystichum species from China are reported. Most of the materials examined were field-fixed in Emei Shan, Sichuan province, and one of them was in Dali Xian, Yunnan province. Only the count of Dryopteris goeringiana was made from the plant brought from Wuling Shan, Beijing and grown in the garden of our Institute. All the materials were fixed in 1:3 acitic acidalcohol, and stained with acetocamine. All the counts were made at diakinesis or metaphase I of meiosis in SMCs .The results of the observation on them are summarized in table 1. Of these, the chromosome numbers for six species are first report. Five species are sexual: diploid: D. goeringiana, D. porosa, D. subinaequalis, D. yui and P. stenoghyllum. Three spe cies are sexual tetraploid: P. acutidens, P. erosum and P. moupingense. Only D. juxtaposita is an apomictic triploid. The vouchers are preserved in the Herbarium of our Institute (PE). We are indebted to Prof. R. C. Ching and C. R. Fraser-Jenkins for identification of the materials.  相似文献   

10.
Recent advances in molecular systematics of the ferns make it possible to address long-standing questions about classification of the major fern genera, such as the worldwide genus Polystichum (Dryopteridaceae), comprising at least 200 species. In this study we examined rbcL sequences and morphological characters from 55 fern taxa: 34 were from Polystichum and 21 were from other genera in the Dryopteridaceae. We found that Phanerophlebia, possibly including Polystichopsis, is the sister group to Polystichum sensu lato (s.l.), including Cyrtomium. Polystichum as commonly recognized is paraphyletic. Our results lead us to suggest recognizing the clade of earliest diverging Polystichum species as a distinct genus (Cyrtomidictyum) and to continue to recognize Cyrtomium as a separate genus, leaving a monophyletic Polystichum sensu stricto (s.s.). We resolved a tropical American clade and an African clade within Polystichum s.s. However, the resemblance between the once-pinnate, bulb-bearing calciphilic species found in Asia and the West Indies appears to be the result of convergent evolution. Optimizing our morphological character transformations onto the combined phylogeny suggests that the common ancestor of Polystichum s.l. and Phanerophlebia had evolved the common features of the alliance, including ciliate petiole-base scales, once-pinnate fronds, ultimate segments with scarious tips, peltate indusia, and microscales.  相似文献   

11.
A genus-wide molecular phylogeny for Polystichum and allied genera (Dryopteridaceae) was reconstructed to address the biogeographic origin and evolution of the three Hawaiian Polystichum species, all endemic there. The analysis was based on the cpDNA sequences rbcL and the trnL-F spacer from a taxonomically and geographically diverse sample. Parsimony and Bayesian phylogenetic analyses of the combined data support a monophyletic Polystichum and corroborate recent hypotheses as to membership and sequence of origin of the major groups within the genus. The Hawaiian Polystichum species are polyphyletic; two separate lineages appear to have arrived independently from the Old World. The provenance of the diploid Polystichum hillebrandii is continental eastern Asia, while the source of the polyploid lineage comprising tetraploid P. haleakalense and octoploid P. bonseyi is likely continental Asia. From our results, the origin of the Hawaiian species of Polystichum, like many Hawaiian fern genera with several species, is the result of multiple migrations to the islands, rather than single migrations yielding nearly all the local diversity as in the angiosperms. This emerging pattern provides a modern test of the premise that propagule vagility has a central role in determining pattern of evolution.  相似文献   

12.
Petrocosmea glabrstoma ZJ. Qiu & YZ. Wang, a new species from Yunnan Province, China, is described and illustrated. The new species is similar to Petrocosmea forrestii Craib and Pmairei Lévl., but differs from them mainly by its leaves triangular or triangular ovate, corolla glabrous inside with shorter filament. Molecular and morphological data demonstrate that this new species has a close affinity to Pforrestii.  相似文献   

13.
Six species and one subspecies of Codonopsis are described from the Pan Himalaya as new in the present article. They are Codonopsis bomiensis, Ccampanulata, Celliptica, Chemisphaerica, Clixianica, Creflexa, and Ccardiophylla Diels ex Kom. subsp. megaphylla. The six new species each is provided with an illustration.  相似文献   

14.
We describe 11 new pteridophyte species belonging to various families from Bolivia: Dennstaedtiaceae:Hypolepis, scandens, Hypolepis minima; Pteridaceae:Cheilanthes glutinosa, Eriosorus angustus, E. ascendens, E. madidiensis; Tectariaceae:Tectaria jimenezii; and Woodsiaceae:Athyrium latinervatum. Diplazium bipinnatum, D. bolivianum, D. yuyoense. The following new combinations are proposed:Anemia australis, Diplazium andicola, D. andinum, andD. petiolulatum.Polystichum maximum is proposed as a new name forPolystichum giganteum.  相似文献   

15.
Morphological, isozyme, and cytological analyses of the small, pale-scaled polystichums from oakdominated montane rain forests in Costa Rica and Mexico reveal the presence of a separable undescribed species endemic to the Cordillera de Talamanca of Costa Rica. The new taxon,Polystichum lilianae, is an allotetraploid hypothesized to have the sympatricP. turrialbae as one diploid progenitor based on isozyme characters. The isozyme and morphometric data also support the inclusion ofP. smithii, described from southern Mexico, inP. turrialbae, described from Costa Rica. The namePolystichum fournieri, formerly used for all of these plants, applies to species endemic to Oaxaca and Chiapas, Mexico. It is not a progenitor ofP. lilianae.  相似文献   

16.
Raphiocarpus jinpingensis WH. Chen & YM. Shui, a new species of Gesneriaceae, is described and illustrated, from the Xilong Mountain of Jinping County in Yunnan, China, bordering to North Vietnam. The new species is similar as Rpetelotii (Pellegr.) Burtt in shapes of corolla and yellowish flowers, and differs from Rpetelotii mainly in its plants with dense pubescence and calyx tubes subequal to calyx lobes.Its pollen grains and seeds are reported here under Scanning Electonic Microscope (SEM).  相似文献   

17.
A new species of Gesneriaceae from Honghe County, Southeastern Yunnan, China, Tremacron hongheense WH. Chen & YM. Shui, is described and illustrated. The new species is similar to Tremacron forrestii Craib, but differs by its leaf blade adaxially sparsely long setose (vs. densely white appressed pubescent and sparsely rusty brown villous), corolla tube outside short white glandular (vs. nearly glabrous), corolla lobes red and thickening at apex, especially adaxial lip (vs. yellow and not thickening), stamens 16-18cm long (vs. 04-12cm long), staminode 05-14cm long (vs. 02-04cm long).  相似文献   

18.
A new Polystichum (Pteridophyta: Dryopteridaceae) species, P. incongruum J.P.Roux sp. nov. from the Western and Eastern Cape Provinces from Soudi Africa is described. This variable species is related to P. pungens (Kaulf.) C.Presl but differs from it in pinnule morphology, the frequent occurrence of glandular cells along the sporangium stalk, the (more rare) occurrence of clavate unicellular glands along the indusium margin and a chromosome number of 2 n = 164.  相似文献   

19.
Morphological characters, chloroplast DNA, and allozymes were used to analyze the distribution of individuals within a hybrid population of the ferns Polystichum munitum and P. imbricans in northwestern California. Microsites within the population were characterized according to soil moisture and light levels reaching the plants. In sites with low soil moisture and high light levels, all of the ferns were genetically and morphologically like P. imbricans. In contrast, ferns with the genetic and morphological identity of P. munitum predominated in moist shady sites. Intermediate sites supported very few P.munitum, a wide variety of hybrid recombinants, and a majority of ferns with P. imbricans characteristics. The pattern of variation within the population is noteworthy because of the close proximity of the habitat extremes and the long-range dispersal of fern spores. We conclude that natural selection along environmental gradients must be a major factor in determining the ecological and genetic associations within the hybrid zone. The results of this study are evaluated in the context of the fern life cycle and compared to the assumptions of models explaining the establishment and maintenance of hybrid zones, which vary in the role attributed to environmentally mediated natural selection.  相似文献   

20.
本文描述了发现自西藏毛茛科唐松草属的一新种,错那唐松草,并给出其与近缘种的区别特征。  相似文献   

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