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61.
Nanocnide zhejiangensis X.F. Jin & Y.F. Lu, a new species of Urticaceae from Zhejiang, east China, is described with illustrations. The new species is morphologically similar to Nanocnide japonica in having staminate inflorescence longer than leaves, but differs by having glabrous stems, petioles, peduncles and abaxial leaf surfaces, glabrous perianth lobes of staminate flowers, dorsally glabrous perianth lobes of pistillate flowers, and acuminate or solitary spinose–setaceous at the apex. Analysis based on ITS, atpF–H, atpB–rbcL and trnL–F sequences also demonstrate that Nanocnide japonica is the closest extant relative to the new species. 相似文献
62.
63.
Wang Wen-tsai 《植物分类学报:英文版》1993,31(2):170-175
Four new species of the genus Elatostema are described. They are E.
coriaceifolium W. T. Wang, E. glochidioides W.T.Wang,E. liboense W.T.Wang,and E. baiseense W. T. Wang 相似文献
64.
头序赤车的特征在于其具花序托和总苞的雌头状花序,根据此一特征即可将它与赤车属的其它所有种区别开。因此,在2002年被错误归并为异名的此赤车属进化种,以及根据其建立的单种进化组头序赤车组在该文中予以恢复。 相似文献
65.
66.
该文描述了荨麻科三新种:(1)自中国重庆市发现的荨麻科荨麻属一新种,城口荨麻。此种与异株荨麻有亲缘关系,区别特征为此种的茎被少数刺毛,叶片多为心形,雄、雌花序均不分枝,瘦果在中央稍凹陷。(2)自中国广西发现的荨麻科赤车属一新种,来宾赤车。此种与特产云南东南部的富宁赤车相近缘,与后者的区别在于本种茎的毛开展或向上弯曲,叶片长椭圆形,基部斜楔形,雌花具3~4枚花被片,其中1~2枚较大花被片在背面顶端具一长筒状突起。(3)自缅甸北部发现的荨麻科楼梯草属一新种,克钦楼梯草。此种在体态上与骤尖楼梯草甚为相似,与后者的区别在于本种的每一茎节具正常叶和一退化叶,托叶狭披针状条形和无脉,雌总苞苞片无角状突起,雌小苞片较大,呈楔状长圆形,雌花具一小花被片,以及雌蕊具一宽倒卵球形柱头。 相似文献
67.
WANG Wen Tsai 《Plant Diversity》2012,34(2):137-144
One variety, Elatostema bijiangense var. weixiense, belonging to sect. Weddellia ser. Crenata, one species, E.cucullatonaviculare, belonging to sect. Elatostema ser. Cuspidata, two species, E.luoi and E.heterogrammicum, belonging to sect. Elatostema ser. nanchuanensia, and one species, E.fugongense, belonging to sect. Elatostema ser. Albopilosa, are described as new from China. 相似文献
68.
Testing Darwin's transoceanic dispersal hypothesis for the inland nettle family (Urticaceae)
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Zeng‐Yuan Wu Jie Liu Jim Provan Hong Wang Chia‐Jui Chen Marc W. Cadotte Ya‐Huang Luo Bruno S. Amorim De‐Zhu Li Richard I. Milne 《Ecology letters》2018,21(10):1515-1529
Dispersal is a fundamental ecological process, yet demonstrating the occurrence and importance of long‐distance dispersal (LDD) remains difficult, having rarely been examined for widespread, non‐coastal plants. To address this issue, we integrated phylogenetic, molecular dating, biogeographical, ecological, seed biology and oceanographic data for the inland Urticaceae. We found that Urticaceae originated in Eurasia c. 69 Ma, followed by ≥ 92 LDD events between landmasses. Under experimental conditions, seeds of many Urticaceae floated for > 220 days, and remained viable after 10 months in seawater, long enough for most detected LDD events, according to oceanographic current modelling. Ecological traits analyses indicated that preferences for disturbed habitats might facilitate LDD. Nearly half of all LDD events involved dioecious taxa, so population establishment in dioecious Urticaceae requires multiple seeds, or occasional selfing. Our work shows that seawater LDD played an important role in shaping the geographical distributions of Urticaceae, providing empirical evidence for Darwin's transoceanic dispersal hypothesis. 相似文献
69.
Maria del Mar Trigo Baltasar Cabezudo Marta Recio Francisco Javier Toro 《Aerobiologia》1996,12(1):85-90
In the Mediterranean area, Urticaceae pollen, together with the pollen of olive and grasses, are the aeroallergens with the highest incidence in the population. From October 1991 to September 1993, with the aid of a Burkard spore-trap, we carried out a study on the Urticaceae pollen content in the atmosphere of Málaga, a seaside resort situated in the Costa del Sol (southern Spain). In Málaga, the Urticaceae pollen season is very long and their pollen grains are detected throughout the year. However, peaks were recorded in March and April and the variables most influencing concentration were maximum air temperature, sunshine hours and relative humidity. Diurnal patterns show that peaks occur generally from 10:00 h to 16:00 h when the temperature reaches its highest values. 相似文献
70.
Maria del Mar Trigo Baltasar Cabezudo Marta Recio Francisco Javier Toro 《Aerobiologia》1996,12(2):85-90
In the Mediterranean area, Urticaceae pollen, together with the pollen of olive and grasses, are the aeroallergens with the
highest incidence in the population. From October 1991 to September 1993, with the aid of a Burkard spore-trap, we carried
out a study on the Urticaceae pollen content in the atmosphere of Málaga, a seaside resort situated in the Costa del Sol (southern
Spain). In Málaga, the Urticaceae pollen season is very long and their pollen grains are detected throughout the year. However,
peaks were recorded in March and April and the variables most influencing concentration were maximum air temperature, sunshine
hours and relative humidity. Diurnal patterns show that peaks occur generally from 10:00 h to 16:00 h when the temperature
reaches its highest values. 相似文献