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1.
Impatiens macrantha S. X. Yu&Ying Qin (Balsaminaceae), a new species from Guangxi, China, is described and illustrated. Phylogenetic analysis based on molecular data shows the new species to belong to I. subg. Clavicarpa and to be closely related to I. tubulosa with which it shares succulent stems and racemose inflorescences, but it can be easily distinguished by having a 4 – or 5 – ridged stem, obovate or elliptic leaf blade, and saccate lower sepal. Furthermore, I. macrantha is distinguishable from other Impatiens in China by its obviously larger leaves and flowers. The evidence from morphology and molecular data both support I. macrantha as new to science.  相似文献   

2.
Impatiens nanlingensis A. Q. Dong & F. W. Xing, a new species of Impatiens (Balsaminaceae) from Guangdong, China, is described and illustrated. It is morphologically similar to I. jinggangensis Y. L. Chen, but differs mainly by its lateral united petals; basal lobes suborbicular, marked with yellow stripes; distal lobes narrowly caudate, apex tailed. It also resembles I. bicornuta, but I. bicornuta differs mainly in its longer peduncles, up to 25 cm, pale blue–purple flowers and broadly sigmoid‐curved–saccate lower sepal.  相似文献   

3.
Impatiens shimianensis Q. Luo (Balsaminaceae), a new species from Shimian county in southwestern Sichuan province, China, is reported and its morphological characteristics are described and illustrated. Pollen grain morphology and seeds under SEM are also described. The new species is somewhat similar to I. bahanensis, I. brachycentra, I. laxiflora, I. parviflora and I. racemosa, but differs mainly by having leaf blades with white short stiff adpressed hairs; basal lobes of lateral united petals triangular, distal lobes lanceolate; and lower sepal salver‐shaped. The distinguishing characters for these six Impatiens species are given in a table.  相似文献   

4.
Trisporangiate anthers were found in four Indian species ofImpatiens (Balsaminaceae),I. barberi, I. clavicornu, I. modesta andI. stocksii, belonging to subgen.Acaulimpatiens. This seems to be the first case of flowering plants characterized by normally formed trisporangiate anthers known to science.  相似文献   

5.
Impatiens pterocaulis S. X. Yu et L. R. Zhang, a new species of the Balsaminaceae from Yancha, Longlin, Guangxi Region, is described and illustrated. This species is similar to I. wilsonii in having nearly white flowers, 4 lateral sepals and a racememos inflorescence, but differs by having winged stems, very short‐spurred lower sepal, yellowish flowers and an acuminate dorsal petal apex. Pollen characters and leaf epidermal micro‐characters of these two species were studied, and the results support that the two species should be kept separate.  相似文献   

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8.
Impatiens liboensis K. M. Liu & R. P. Kuang, a new species collected from Xiaoqikong Scenic Area in southern Guizhou, China, is described and illustrated, including its seed and pollen micro‐morphology. Impatiens liboensis is similar to I. chishuiensis Y. X. Xiong and I. tubulosa Hemsl., but differs by having obviously irregular underground tubers, white or pink–white flowers, lower sepal with a 1.2–1.5 cm long spur, obovate dorsal petal, and obovate‐oblong or obliquely obovate lower lobes of the lateral petals with retuse apex.  相似文献   

9.
采用扫描电镜观察了中国四川雅安地区13种凤仙花属植物的花粉形态,并对其花粉形态进行了主成分分析和聚类分析,基于孢粉学和SRAP聚类结果的比较,讨论不同孢粉学特征对分类结果的影响。结果显示:(1)雅安地区13种凤仙花属植物花粉粒均为中等大小,花粉粒形状从超扁到扁球形变化,花粉粒极面观形状从矩形和椭圆形到四边形、圆形、三角型变化,且只有湖北凤仙、峨眉凤仙和匙叶凤仙是三沟花粉粒,其余种均为四沟花粉粒;外壁纹饰仅扭萼凤仙和齿萼凤仙为细小网状,其余均为网状纹饰。(2)依据不同指标进行的孢粉学聚类均将13种凤仙花属植物划分为3个类群,而SRAP聚类结果则将13种凤仙花属植物划分为5个类群;不同孢粉学聚类结果的相似率只有30.77%。(3)孢粉学聚类并未与分子聚类显示严格的对应关系,以花粉大小和形状、外壁纹饰为指标进行的孢粉学分类与SRAP分类的相似率最高(69.23%)。研究认为,选择不同的花粉形态特征作指标对分类的准确性影响较大,花粉大小和形状、外壁纹饰这2个指标对凤仙花属植物分类具有意义,而萌发沟的特征则很难作为分类的依据,花粉形态特征在分类上有局限性;进行该属植物孢粉学分类需要选择有价值的分类指标,并结合形态学、分子生物学等综合研究。  相似文献   

10.
Impatiens pingxiangensis H. Y. Bi & S. X. Yu (Balsaminaceae), a new species from the limestone areas in Guangxi, China, is described and illustrated. The new species is similar to I. obesa in having succulent stems, subsessile peduncle, tufted pedicel and the lower petal in each pair of lateral united petals being connate, but differs from the latter by having perennial stems, leaf blades with 7–9 pairs of lateral veins, 1–2‐flowered racemes, ovate inner lateral sepals, and elliptic capsule. Moreover, the pollen and seed coat characters also support the recognition of the new species.  相似文献   

11.
A new species of Impatiens L. from Hubei, China, Impatiens zhuxiensis Q.L. Gan & X.W. Li, is described and illustrated. Impatiens zhuxiensis resembles I. nasuta Hook. f. and I. compta Hook. f. and these are the only species in I. sect. Impatiens with a long abaxial rostrum on the midvein of the dorsal petal. However, the flowers of I. zhuxiensis are yellow while those of I. nasuta and I. compta are deep purple-red and pale purple-blue, respectively; I. zhuxiensis has the midvein of the dorsal petal abaxially elongated into a pointed rostrum near the apex, whilst the rostrum of I. nasuta is elephant-trunk-shaped near the middle, and that of I. compta is recurved near the apex. A molecular phylogenetic analysis of Impatiens based on ITS, atpB-rbcL and trnL-F supported these three species as closely allied and that they belong to I. sect. Impatiens.  相似文献   

12.
该文报道重庆市1新记录种——太子凤仙花(Impatiens alpicola Y.L.Chen et Y.Q.Lu),并描述该新记录种的形态特征和生境分布,凭证标本存放于重庆三峡学院生命科学与工程学院植物标本馆。另编制了重庆市分布凤仙花属植物分种检索表。  相似文献   

13.
Chirita tiandengensis Fang Wen & Hui Tang, a new species of Chirita from Guangxi, China, is described and illustrated. The new species is similar to C. napoensis Z. Y. Li, C. lunglinensis W. T. Wang and C. obtusidentata W. T. Wang, but differs by leaf blades ovate‐lanceolate, both surfaces sparsely strigulose; cymes 5‐ or 8‐flowered, bracts narrowly lanceolate, 6–8×1.5–2.0 mm; larger flowers (3.8–4.6 cm long), pink corolla, infundibuliform‐tubular tube; backside of anthers puberulous, filaments straight; staminodes glabrous, fused on the capitate top; stigma bipartite to the base with narrowly lanceolate lobes.  相似文献   

14.

Background and Aims

The family Balsaminaceae is essentially herbaceous, except for some woodier species that can be described as ‘woody’ herbs or small shrubs. The family is nested within the so-called balsaminoid clade of Ericales, including the exclusively woody families Tetrameristaceae and Marcgraviaceae, which is sister to the remaining families of the predominantly woody order. A molecular phylogeny of Balsaminaceae is compared with wood anatomical observations to find out whether the woodier species are derived from herbaceous taxa (i.e. secondary woodiness), or whether woodiness in the family represents the ancestral state for the order (i.e. primary woodiness).

Methods

Wood anatomical observations of 68 Impatiens species and Hydrocera triflora, of which 47 are included in a multigene phylogeny, are carried out using light and scanning electron microscopy and compared with the molecular phylogenetic insights.

Key Results

There is much continuous variation in wood development between the Impatiens species studied, making the distinction between herbaceousness and woodiness difficult. However, the most woody species, unambiguously considered as truly woody shrubs, all display paedomorphic wood features pointing to secondary woodiness. This hypothesis is further supported by the molecular phylogeny, demonstrating that these most woody species are derived from herbaceous (or less woody) species in at least five independent clades. Wood formation in H. triflora is mostly confined to the ribs of the stems and shows paedomorphic wood features as well, suggesting that the common ancestor of Balsaminaceae was probably herbaceous.

Conclusions

The terms ‘herbaceousness’ and ‘woodiness’ are notoriously difficult to use in Balsaminaceae. However, anatomical observations and molecular sequence data show that the woodier species are derived from less woody or clearly herbaceous species, demonstrating that secondary woodiness has evolved in parallel.  相似文献   

15.
Impatiens chashanensis H. Y. Bi & S. X. Yu (Balsaminaceae), a new species from the Sichuan Province in China, is described and illustrated. In comparison with the morphologically close I. dicentra , both species have succulent stems and the lobes of the lateral united petals end in a long hair, but I. chashanensis differs in having white flowers, four lateral sepals, lacerate apex of the inner sepal, shorter spur with swollen, slightly bifid apices. Moreover, leaf epidermal characters also support the recognition of the new species.  相似文献   

16.
《Journal of bryology》2013,35(2):105-108
Abstract

Frullania larjiana Sushil K. Singh & Singh is described as a new species from the Western Himalaya, India. The species is characterized by ovate-suborbicular leaf lobes that are truncate at their antical bases; uniformly lanceolate–explanate lobules, 0.15?0.17 × 0.0?0.09 mm with a vestigial stylus 1–2 cells long; small underleaves, 0.16?0.3 × 0.1?0.15 mm; obovate to oblong-obovate female bract lobes; triangular lanceolate bract lobules without a stylar tooth and an obovoid, smoothly 5-keeled, shortly beaked perianth.  相似文献   

17.
中国凤仙花科植物叶表皮特征及其分类学意义   总被引:1,自引:0,他引:1  
利用光学显微镜观察凤仙花科106份样本材料、36种代表植物的叶表皮微形态特征。结果表明:该科植物叶表皮微形态特征种内稳定,对于种间及属间关系的界定具有重要的分类学价值。上表皮细胞的形状及垂周壁的式样种间差异明显,各分类群间有明显的界限,是种间界定的重要依据,因此上表皮微形态特征具有重要的的分类学价值,基于上表皮的微形态特征将研究的36种代表植物划分为5个类型。下表皮的微形态特征虽更为多样,种间差异显著,可用于种间界定,但对于属下划分难以提供有价值的性状。该科植物叶表皮微形态特征与宏观形态特征的相关性较弱,与地理分布格局的相关性较强,关系更为密切。同一地理分布区域内的种类宏观形态特征虽然差别明显,但叶表皮微形态特征却表现出较强的一致性,这似乎也反映了叶表皮微形态这一性状受环境饰变的影响比较明显。综上所述,叶表皮微形态特征可为凤仙花科的系统发育,尤其是凤仙花属种间界定提供有价值的分类学佐证  相似文献   

18.
Floral variation among closely related species is thought to often reflect differences in pollination systems. Flowers of the large genus Impatiens are characterized by extensive variation in colour, shape and size and in anther and stigma positioning, but studies of their pollination ecology are scarce and most lack a comparative context. Consequently, the function of floral diversity in Impatiens remains enigmatic. This study documents floral variation and pollination of seven co‐occurring Impatiens spp. in the Southeast Asian diversity hotspot. To assess whether floral trait variation reflects specialization for different pollination systems, we tested whether species depend on pollinators for reproduction, identified animals that visit flowers, determined whether these visitors play a role in pollination and quantified and compared key floral traits, including floral dimensions and nectar characteristics. Experimental exclusion of insects decreased fruit and seed set significantly for all species except I. muscicola, which also received almost no visits from animals. Most species received visits from several animals, including bees, birds, butterflies and hawkmoths, only a subset of which were effective pollinators. Impatiens psittacina, I. kerriae, I. racemosa and I. daraneenae were pollinated by bees, primarily Bombus haemorrhoidalis. Impatiens chiangdaoensis and I. santisukii had bimodal pollination systems which combined bee and lepidopteran pollination. Floral traits differed significantly among species with different pollination systems. Autogamous flowers were small and spurless, and did not produce nectar; bee‐pollinated flowers had short spurs and large floral chambers with a wide entrance; and bimodally bee‐ and lepidopteran‐pollinated species had long spurs and a small floral chamber with a narrow entrance. Nectar‐producing species with different pollination systems did not differ in nectar volume and sugar concentration. Despite the high frequency of bee pollination in co‐occurring species, individuals with a morphology suggestive of hybrid origin were rare. Variation in floral architecture, including various forms of corolla asymmetry, facilitates distinct, species‐specific pollen‐placement on visiting bees. Our results show that floral morphological diversity among Impatiens spp. is associated with both differences in functional pollinator groups and divergent use of the same pollinator. Non‐homologous mechanisms of floral asymmetry are consistent with repeated independent evolution, suggesting that competitive interactions among species with the same pollination system have been an important driver of floral variation among Impatiens spp.  相似文献   

19.
Mechanisms of interference through improper pollen transfer are described for sympatric populations of the simultaneously flowering annuals Impatiens capensis and I. pallida. Stigmas of both Impatiens species are receptive to conspecific pollen from the time of androecium disarticulation until after perianth drop. Pollen of I. pallida adheres to, and germinates on, the stigmas of I. capensis. The pollen tubes reach the ovules but do not fertilize them. In contrast, pollen of I. capensis adheres poorly to I. pallida stigmas and fails to germinate. Pollen mixtures of the two Impatiens species cause a much greater reduction in fruit set in I. capensis than in I. pallida. Despite the interference of I. pallida pollen, I. capensis persists in mixed populations with I. pallida by: 1) possessing stigmas receptive to pollen throughout the female phase; 2) having the ability to produce a full seed complement via one pollination event; and 3) possessing cleistogamous flowers to ensure sexual reproduction.  相似文献   

20.
为探究凤仙花近缘种植物的细胞学和微形态学方面的亲缘关系,该文选取荔波凤仙花(Impatiens liboensis)及近缘种赤水凤仙花(I.chishuiensis)和管茎凤仙花(I.tubulosa)的根尖和叶表皮为实验材料,采用体细胞染色体常规压片法和叶表皮光学显微镜观察法对凤仙花近缘种植物进行染色体及叶表皮特征研...  相似文献   

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