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1.
Carex yandangshanica C. Z. Zheng & X. F. Jin, a new species of Carex sect. Rhomboidales Kükenth. from Zhejiang, China, is described and illustrated. The new species is similar to C. thibetica Franch. and C. brevicuspis C. B. Clarke, but differs from the former by having trabeculate leaves, pistillate spikes with 6–10 staminate flowers or without staminate flower at the apex, and achenes at apex contracted into a slightly curved beak, and from the latter by having lateral culms, trabeculate leaves, and elliptic, rubiginous and awned pistillate scales. SEM microphotographs of perigynia and achenes are provided for the new species and related taxa.  相似文献   

2.
Carex zhejiangensis X. F. Jin, Y. J. Zhao, C. Z. Zheng & H. W. Zhang, a new species of Carex sect. Rhomboidales sensu Kükenthal (Cyperaceae) from Zhejiang, eastern China, is described with illustrations. This new species is morphologically similar to C. filipes and C. macroglossa. Compared to C. filipes, C. zhejiangensis has elongated rhizomes, scattered culms, rather densely flowered pistillate spikes, achenes shortly stipitate at the base, and styles erect at the base. In contrast, C. filipes has short rhizomes, caespitose culms, sparsely flowered pistillate spikes, achenes obscurely stipitate at the base, and styles curved at the base. C. zhejiangensis differs from C. macroglossa by having elongated rhizomes and scattered culms, pistillate scales awned at apex, and perigynia contracted to a narrowly infundibuliform beak at apex. Diagnostic morphological characters, which are based upon population sampling, were analyzed in Carex zhejiangensis sp. nov., C. filipes and C. macroglossa.  相似文献   

3.
Carex qingliangensis D. M. Weng, H. W. Zhang & S. F. Xu, a new species of the Cyperaceae from Zhejiang, China, is described with illustrations. The new species is morphologically similar to C. dolichostachya Hayata and C. tianmushanica C. Z. Zheng & X. F. Jin, but differs from the former in having perigynia sparsely pubescent and achenes constricted into a short neck at apex. It differs from the latter in having achenes not contracted in the middle part.  相似文献   

4.
Having mixed extremely various patterns of achenes for a long time in the genus Lactuca L., especially showed in the classification of it on the mainland of Asia, Lactuca L., the primary unnatural genus, becomes more nuclear in its limit. The present paper makes a revision to attempt providing a clear cline between Lactuca L. and its relative genera. On my opinion, only plants, represented by Lactuca sativa L., which have ovoid capitulum during its fruiting, numerous (7-25), yellow ligular florets and longitudinal 1-10 ribs or striae on each side of achenes, acute into filiform beak at its apex, should be defined as Lactuca L. In view of the present concept of Lactuca L., another group of plants, embodied by Lactuca indica L., having its broadening, thin winged-margin of, 1-3 striae on each side of achenes, black, dorsi-ventral compressed, acute into thick and short beak at its apex, evidently, should not be placed into Lactuca L., but be regarded as genus, i.e. Pterocypsela Shih, gen. nov. Pterocypsela Shih distributes in Eastern and southern Asia, where Lactuca L. does not occur. In China there is all of species, seven species, of Pterocypsela Shih. They are P. raddeana (Maxim.) Shih, P. indica (L.) Shih, P. elata (Hemsl.) Shih P. lacciniata (Houtt.) Shih, P. triangulata (Maxim.) Shih, P. sonchus (Lévl.) Shih and P. formosana (Maxim.) Shih, But in Mediterranean regions and Middle and Western Asia mainly distributes Lactu ca L., in which there are only seven species from western China, Xijiang autonomic district. They are L. dolichophylla Kitam., L. sativa L., L. altaica Fisch. et Mey., L. serriola Torner, L. dissecta Don, L. auriculata DC. and L. undulata Ledb. With the combination of violet-purple ligular florets non-ovoid capitulum during its fruiting, a little thick achenes, acuminate into longer. or short beak at its apex and 4-6 ribs on each side of it, Mulgedium tataricum (L.) DC. is evidently different from Lactuca sativa L. with combination of ovoid capitulum during its fruiting, yellow ligular florets and compres sed achenes, acute into filiform beak at its apex. There seems to be no point in refusing Mu lgedium Cass. as a genus. Strictly speak, Mulgedium Cass. seems to be reminiscent of Para prenanthes Chang (see bellow) without beak at the apex of its achenes. In Hengduan moun tains and mountain range of Himalayas M. tataricum (L.) DC. discoveries its relative par tners. They are M. bracteatum (Mook. f. ex. C. B. Clarke) Shih, M. lessertianum (Wall. ex C. B. Clarke) DC., M. monocephalum (Chang) Shih, M. umbrosum (Dunn) Shih, M. meridionale Shih and M. polypodifolium (Franch.) Shih. Having broadering and thickening margin and 4-7 striae on each side of achenes, grey, dorsi-ventral compressed, truncate and beakless at its apex, Lactuca sibirica (L.) Benth. ex Maxim. (Sonchus sibiricus L.) is not only different from Lactuca sativa L. with the combination of yellow ligular florets and filiform beak at apex of its achenes, but also from the genus Mulgedium Cass. with beak at apex of its achenes. Therefore, Lagedium Sojak, established by J. Sojak (1961), should be restored. It should be point out that Lagedium Sojak is monotypic genus excluding Mulgedium tataricum (L.) DC. with beak at the apex of its achenes, non-marginated. Lagedium Sojak widely distributes in temperate and frigid zone ofvnorthern hemisphere. In our country, Lagedium sibiricum (L.) Sojak, sole species of the genus, restricts its northeast region. Paraprenanthes Chang, the new genus, established by Ch. Ch. Chang (1950) based on Lactuca sororia Miq. and Lactuca yunnanensis Franch. seems to be a distinct genus. This genus is characterized by 4-6 ribs on each side of achenes, black, fusiform, a little thick and beakless at its apex. Besides above-mentioned two species, assigned by Chang, in forest of tropic and subtropic zones on the mainland of Asia there are many species with same structure in achenes like L. sororia Miq. and L. yunnanensis Franch. The genus Paraprenanthes Chang seems to be reminiscants of Mulgedium Cass. and Lagedium Sojak, but differs from the former in its beakless achenes, from the later in its non-marginated achenes and 4-6 ribs on each side of it. In our country, there are all species of the genus known in the tropic and subtropic zones on the mainland of Asia. They are P. sororia (Miq.) Shih, P. yunnanensis (Franch.) Shih, P. longiloba Ling et Shih, sp. nov., P. heptontha Shih et D. J. Liou, sp. nov., P. prenanthoides (Hemsl.) Shih, P. pilipes (Migo) Shih, P. thirionii (Lévl.) Shih, P. sylvicola Shih., sp. nov., P. multiformis Shih, sp. nov., P. auriculiformis Shih, sp. nov. and P. sagittiformis Shih, sp. nov.  相似文献   

5.
A new species of Carex sect. Rhomboidales, C. jianfengensis, is described and illustrated from Hainan, China. The new species is similar to C. zunyiensis but differs in having involucral bracts sparsely hispid and with ca.1 cm long sheaths; inflorescence with 4 spikes, terminal spike ca. 2.5 cm long, lateral spikes 2–3.5 × 0.7–1 cm; staminate glumes narrowly ovate, ca. 5 mm; pistillate glumes triangular-lanceolate, 5–7 mm; perigynia 6–8 × 3 mm and pubescent on veins; nutlet 4–5 mm long, rhombic-ovoid, trigonous, base with shortly stipitate, apex abruptly contracted into a erect short beak, and not expanding into an annulate orifice.  相似文献   

6.
Calligonum taklimakanense B. R. Pan & G. M. Shen, a new species of Polygonaceae from Taklimakan Desert, Xinjiang, China, is described and illustrated. It is closely related to C. ebinuricum Ivanova ex Soskov in having similar fruit shape and achenes with two rows of bristles, but differs in straight old branches and slightly coiled achenes without a long beak. Calligonum ebinuricum has tortuous old branches, very coiled achenes, and a 2–4 mm long beak.  相似文献   

7.
在重庆市北碚区缙云山野外植物调查过程中,于海拔500~800 m的溪边阴湿沟谷中发现一种荨麻科植物,虽然该物种雌花序具花序托,但因其雌花花被片5枚,外面先端具角状突起,瘦果只具瘤状突起,更符合赤车属的特征,且结合分子系统学证据,该物种明显属于赤车属.该物种的特征在于其具花序托和总苞的雌花序,根据这一特征可将其置于头序赤...  相似文献   

8.
Carex sinosupina, a new species from Gansu, China is described and illustrated. This species is similar to C. aridula and C. ivanoviae, but differs by having broader leaves, 2.0–3.5 mm wide, perigynia 3–5‐veined abaxially and achenes concave at the middle of one lateral surface. Based on a field survey and SEM (scanning electron microscope) observation of the micromorphology of perigynia and achenes, the morphology and micromorphology of the new species, C. aridula and C. ivanoviae is compared.  相似文献   

9.
A new species of the orchid genus Myoxanthus, M. oliviae, is described based on Peruvian material. The novelty resembles M. serripetalus from which it differs by the 7–8‐veined lateral sepals (versus 6‐ or 9‐veined), the petals contracted below the apex and expanded again into a sagittate apex (versus apex caudate) and entire lip middle lobe (versus fimbriate). The flowers of M. oliviae are pale brownish‐purple, internally intensively suffused with yellow, dark‐purple spotted. The new species grows among rocks at the elevation of 2700–3100 m a.s.l. A key to Peruvian Myoxanthus representatives is provided.  相似文献   

10.
This study focuses on the morphological variability of Lactuca serriola achenes in relation to eco-geographic features. Fifty L. serriola populations from four European countries, Czech Republic, Germany, the Netherlands and United Kingdom, were studied. Five morphological characters of the achenes - length and width of achene, length/width index, length of beak, and number of ribs - were evaluated. Significant differences exist in achene morphology of two leaf forms of L. serriola, forma serriola and forma integrifolia. Achenes of f. serriola are shorter, thinner, shorter beaked, lower length/width index, and higher number of ribs compared to f. integrifolia. There was significant variation in the measured characters. Statistical analysis indicated that achene length and width increased along an east-west transect from 2.95 to 3.35 mm and 0.93 to 1.00 mm, respectively. Mean beak length had a similar trend with the exception of German achenes. They had shorter beaks than achenes originating from the Czech Republic with 4.38 and Germany with 4.33 mm. The same trend was evident for L/W index from Czech with a ratio of 3.21 and Germany with 3.14. The number of ribs increased from east to the west in continental Europe, whereas the lowest number of ribs was recorded in achenes collected in Czech with 10.89 and the UK with 10.59. Achene morphology was significantly correlated with three eco-geographic features; longitude, latitude, soil texture of the habitats. The other eco-geographic factors, altitude and population size, did not significantly correlate with the studied characters of L. serriola achenes.  相似文献   

11.
Carex dapanshanica X. F. Jin, Y. J. Zhao & Z. L. Chen, a new species of Cyperaceae from Mount Dapan, Zhejiang Province, eastern China is described and illustrated. The new species is morphologically similar to C. chungii C. P. Wang, but differs in having 2 or 3spikes, pistillate scales with brown margins and short‐awned at apex, and glabrous perigynia. Micromorphological photographs of the achenes of C. dapanshanica and C. chungii under SEM (scanning electron microscope) are provided as well.  相似文献   

12.
该文描述了自云南西北部发现的毛茛科银莲花属一新组,即维西银莲花组(sect. Deinostigma)和一新种,即维西银莲花(Anemone weixiensis)。此组与卵叶银莲花组有亲缘关系,与后者的区别在于其心皮较少(约11枚),子房被短柔毛,柱头明显,呈椭圆体形,瘦果被短柔毛,不扁,无肋,顶端具椭圆体形宿存柱头。  相似文献   

13.
Govenia rubellilabia, a new terrestrial orchid from Sierra Madre de Chiapas, Mexico, is described and illustrated. Diagnostic characters of this new species are compared with other species ofGovenia. Govenia rubellilabia is similar in appearance toG. matudae, but it can be distinguished from this species by a shorter inflorescence with fewer flowers, green-yellowish tepals, a reddish lip lacking spots in the margin of the apex, and by a shorter anther beak.  相似文献   

14.
After having examined all specimens of the genus Prenanthes L. of Compositae in the Herbarium of Institute of Botany, Academia Sinica, I find that the classic concept on the genus Prenanthes established by G. Bentham in 1873 has not been held exactly by some of European, American, Japanese and Chinese botanists. For example, W. B. Hemsley, S. T. Dunn, A. Franchet, S. Kitamura and C. C. Chang placed plants from China which belong to other groups into the genus; I also find that the classic concept of the genus is not clear. The present paper makes a revision not only on the classic concept of the genus, but also on its concept assumed by the above-mentionded botanists. With the combination of numerous (25-35), white or yellow ligular florets, numerous ribs of achenes, Prenanthes alba L. (Nabalus albus (L.) Shih, comb. nov.) is distinctly different from Prenanthes purpurea L., which has the combination of purple, few (5-15) ligular florests and few ribs of achenes. Nabalus Cass., as a genus established early (1825) by H. Cassini, should be restored. It is not reasonable to treat Nabalus as a subgenus (E. B. Babcock et al. 1947) or a section (S. Kitamura, 1956) or as a synonym (G. Bentham, 1983) of the genus Preanathes L. The present author recognizes seven species in the new revised genus Prenanthes L. in China, 4 of which are described as new. In the genus Nabalus Cass. only one species, N. ochroleuca Maxim., is distributed in Northeast China. As Lactuca melanantha Franch. (1895), Prenanthes henryi Dunn (1903), P. glandulosa Dunn (1903), Lactuca triflora Hemsl. (1888) (it was transferred to Prenanthes L. by C. C. Chang in 1934), Prenanthes formosana Kitam. (1934) and P. wilsoni Chang (1934) all have campanulate involucres, purple phyllaries, purple dorsi-ventrally compressed achenes, longitudinal rids 6-9 on each side of achene truncate and beakless at its apex and pilose tubes of corollae, they should be placed neither into the genus Prenanthes with obtusely tri-or pentagonous, subterete achenes and glabrous tubes of corollae, nor into the genus Lactuca with beak achenes. Besides the above-mentioned species misnamed by some of foreign and Chinese botanists, 6 other species also have the same structure in achenes and corollae. Evidently, they fall into a new genus with the name Notoseris Shih. The new genus Notoseris Shih of the tribe Lactuceae of Compositae seems to be more reminiscent of Lactuca L. than of Prenanthes L. emend. All the 12 species of the genus Notoseris Shih are endemic to China and distributed in the area of south of Yantze River. Of them 6 are new combinations and 6 are described as new.  相似文献   

15.
16.
Artemisia sphaerocephala and A. ordosica are two dominant shrub species in Mu Us sandy land (Inner Mongolia, China) and are widely used for vegetation restoration. However, there are two different conclusions about the effect of light on their germination: light promotes germination versus light inhibits germination. The aim of this study was to evaluate these two conclusions and relate the results to instances of failure of these two species to germinate well when air-dispersed in revegetation projects. The effects of fluctuating temperature, light/dark, source (population), position on mother plant, storage condition, and storage time were tested on germination of achenes of these two species. At low temperature, final percent germination (FPG) of achenes in dark and nearly dark conditions was significantly higher than those in light. At 10:20°C, achenes of both A. sphaerocephala and A. ordosica had higher FPG in dark than in light regardless of source, position on mother plants or storage condition. At suboptimum (5:15°C) and supraoptimal (25:35°C) temperatures, germination of A. sphaerocephala and A. ordosica achenes was inhibited in both light and darkness. It was concluded that light inhibits germination of A. sphaerocephala and A. ordosica achenes at low (10:20°C) temperature but not at high (15:25°C) temperature. Since the temperature in Mu Us sandy land is around 10:20°C in early June, when air sowing is done, achenes should germinate best when they are covered by a thin layer of sand.  相似文献   

17.
Wm. Wayt Thomas 《Brittonia》1986,38(4):314-316
While preparing a treatment of the genusRhynchospora forFlora Mesoamericana, a new species from Cerro Pirre was discovered.Rhynchospora pirrensis, described and illustrated here, can be distinguished from other species in sectionPaniculatae by its long, broad, mostly basal leaves and its punctatepapillose achenes. A key to all the broad-leaved species of that section is provided.  相似文献   

18.
Carex ozarkana, a new species from Arkansas, Oklahoma, and extreme northeasternmost Texas is described and illustrated. It is a distinctive regional endemic of mineral soil wetlands most similar to the widespreadCarex albolutescens andC. longii but differing in its elongate, nodding inflorescences (on robust plants), prominently clavate spikes with elongate staminate bases, reddish brown pistillate and staminate scales, and wider achenes with a long apiculum.  相似文献   

19.
New chloranthaceous floral structures from the Late Cretaceous (Late Santonian/Early Campanian) of Scania, southern Sweden, have provided important new information on theChloranthistemon plants. The material includes well preserved fragments of inflorescence axes with flowers in situ documenting thatChloranthistemon flowers were bisexual and closely resembled those of extantChloranthus (Chloranthaceae). An emended diagnosis is given for the type species of the genus,Chloranthistemon endressii, and a new species,C. alatus, is described. The flowers ofChloranthistemon are small, perianthless and strongly zygomorphic, consisting of a tripartite and broadened androecium borne in an abaxial to lateral position on the monocarpellate ovary, and arranged in the axils of decussate bracts. Stamens are either completely free (C. alatus), or free at the base and coherent at the apex (C. endressii). The apical connective is extensive in both species; elaborated into conspicuous wing-like structures inC. alatus, or into a massive and shield-like structure inC. endressii. Pollen grains ofC. endressii are spheroidal, and reticulate and spiraperturate, while those ofC. alatus are ellipsoidal, tectate and foveolate with a unique combination of a distal colpus and a proximal furrow (colpus?) perpendicular to each other. Ovaries observed in well preserved flowers of both species are small and undifferentiated. Larger, dispersed fruits of chloranthaceous affinity are abundant and distinct, and probably represent at least two or three species, but cannot be linked with certainty to any of theChloranthistemon species described here.  相似文献   

20.
Machaeranthera heterocarpa, a new species from southern Texas, is described and illustrated. It is closely related to M. tenuis of Trans-Pecos Texas, is described Mexico from which it differs most notably in stem pubescence, fruit morphology, and chromosome number. The adaptive significance of the heteromorphic achenes of this new species is discussed.  相似文献   

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