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1.
Lu Ling-Ti 《植物分类学报:英文版》1983,21(1):13-25
The genus Rubus is one of the largest genera in the Rosaceae, consisting of more
than 750 species in many parts of the world, of which 194 species have been recorded
in China.
In the present paper the Rubus is understood in its broad sense, including all the
blackberries, dewberries and raspberries, comprising the woody and herbaceous kinds.
So it is botanically a polymorphic, variable and very complicated group of plants.
The detailed analysis and investigation of the evolutionary trends of the main organs
in this genus have indicated the passage from shrubs to herbs in an evolutionary line,
although there is no obvious discontinuity of morphological characters in various taxa.
From a phylogenetic point of view, the Sect. Idaeobatus Focke is the most primitive
group, characterized by its shrub habit armed with sharp prickles, aciculae or setae,
stipules attached to the petioles, flowers hermaphrodite and often in terminal or axillary inflorescences, very rarely solitary, druplets separated from receptacles. Whereas
the herbaceous Sect. Chamaemorus L. is the most advanced group, which is usually
unarmed, rarely with aciculae or setae, stipules free, flowers dieocious, solitary, druplets adhering to the receptacles and with high chromosome numbers (2n = 56).
Basing upon the evolutionary tendency of morphological features, chromosome numbers of certain species recorded in literature and the distribution patterns of species,
a new systematic arrangement of Chinese Rubus has been suggested by the present
authors. Focke in his well-known monograph divided the species of Rubus into 12
subgenera, while in the Flora of China 8 sections of Focke were adapted, but some important revisions have been made in some taxa and Sect. Dalibarda Focke has been
reduced to Sect. Cylactis Focke. In addition, the arrangement of sections is presented
in a reverse order to those of Focke’s system. The species of Rubus in China are
classified into 8 sections with 24 subsections (tab. 3) as follows: 1. Sect. Idaeobatus,
emend. Yü et Lu(11 subsect. 83 sp.); 2. Sect. Lampobatus Focke (1 sp.); 3. Sect.
Rubus (1 sp.); 4. Sect. Malachobatus Focke, emend. Yü et Lu (13 subsect. 85 sp.); 5.
Sect. Dalibardastrus (Focke)Yü et Lu (10 sp.); 6. Sect. Chaemaebatus Focke (5 sp.);
7. Sect. Cylactis Focke, emend. Yü et Lu (8 sp.); 8. Sect. Chamaemorus Focke (1 sp.).
In respect to the geographical distribution the genus Rubus occurs throughout the
world as shown in tab. 2, particularly abundant in the Northern Hemisphere, while
the greatest concentration of species appears in North America and E. Asia. Of the
more than 750 species in the world, 470 or more species (64%) distributed in North
America. It is clearly showm that the center of distribution lies in North America at
present time. There are about 200 species recorded in E. Asia, of which the species
in China (194) amount to 97% of the total number. By analysis of the distribution
of species in China the great majority of them inhabit the southern parts of the Yangtze
River where exist the greatest number of species and endemics, especially in southwestern parts of China, namely Yunnan, Sichuan and Guizhou (tab. 3. 4.). It is interesting to note that the centre of distribution of Rubus in China ranges From northwestern Yunnan to south-western Sichuan (tab. 5), where the genus also reaches its
highest morphological diversity.
In this region the characteristics of floristic elements of Rubus can be summarized
as follows: it is very rich in composition, contaning 6 sections and 94 species, about
66% of the total number of Chinese species; there are also various complex groups,
including primitive, intermediate and advanced taxa of phylogenetic importance; the
proportion of endemic plants is rather high, reaching 61 species, up to 44% of the
total endemics in China. It is noteworthy to note that the most primitive Subsect.
Thyrsidaei (Focke) Yü et Lu, consisting of 9 endemic species, distributed in southern
slopes of the Mts. Qin Ling and Taihang Shan (Fig. 4). From the above facts we may
concluded that the south-western part of China is now not only the center of distribution and differentiation of Rubus in China, but it may also be the center of origin ofthis genus. 相似文献
2.
Fu De-Zhi 《植物分类学报:英文版》1988,26(4):249-264
The genus Dichocarpum was established by W. T. Wang and Hsiao in 1964, who
divided the genus into 2 sections: Sect. Dichocarpum including 10 species distributed on the
mainland of E. Asia, and Sect. Hutchinsonia including 9 species native to Japan. M. Tamura
and L. A. Lauener made a revision of the genus in 1968, who divided the genus into 4 sections, three for the species of the mainland of E. Asia, including 3 series and 10 species, and
the other for the species of Japan, including 2 subsections, 3 series and 9 species. In the present paper, the genus is divided into 2 sections and 6 series, including 15 species and 3 varieties, and a putative phylogeny of the genus is proposed. The genus may be close to the genus
Asteropyrum, and these two genera are rather specialized in Thalictroides (Ranunculaceae),
because they have three very similar characters: the petal with a long claw, the stephanocolpate
pollen and the chromosome morphology. The genus has 2n=24, 35(36?), which indicates that
its basic number is X=6, and the species on the mainland of E. Asia (Sect. Dichocarpum)
may well be paleotetraploids, whereas those in Japan (sect. Hutchinsonia) are paleohexaploids. Most of the advanced species are distributed in Japan and the most primitive ones in
China and the Himalayas, the distribution pattern seggests that the Japanese members of this
genus might have immigrated from China in the Tertiary, and differentiated and evolved
there. The putative phylogeny of the genus is shown in Fig. 2 (at series level) 相似文献
3.
4.
Zhang Zhi-Yun 《植物分类学报:英文版》1988,26(5):394-403
The morphological characters in the genus Orobanche were evaluated from the
taxonomic point of view. The author finds that the plants of this genus are relatively similar
to each other in respect to characters of vegetative organs, fruits and seeds. But the differences
in the floral structures can be served as a basis for delimitating infrageneric taxa. The seed
coat of 18 species and pollen grains of 6 species were also examined under scanning electron
microscope (SEM). They seem to have little significance for distinguishing species.
The result supports G. Beck’s (1930) division of the genus Orobanche into 4 sections, of
which 2 occur in China, based on the characters of the inflorescence, bracteoles and calyx.
The author considers that some characters, such as anther hairy or not, upper lip of corolla
entire or not, lower lip longer or shorter than the upper one, the state of corolla-tube inflec tion and the hair type of filaments and plants, are important in distinguishing Chinese species.
A key to the species of Orobanche in China is given.
This genus consists of about 100 species, and is mostly confined to Eurasia, with over 60
species found in Caucasus and Middle Asia of USSR, where may be the mordern distribu tional centre.
Orobanche L. in China is represented by 23 species, 3 varieties and l forma. As shown in
Table 1, most species (12 species) are found in Xinjiang, which clearly shows a close floristic
relationship between this region and Middle Asia of USSR. 6 species are endemic to China,
of which 4 are confined to the Hengduan Mountains (Yangtze-Mekong-Salwin divide).
The relationships between this genus and related ones of Orobanchaceae are also discussed.
The author holds the following opinions: the genus Phelypaea Desf. should be considered as a
member of Orobanche L. Sect. Gymnocaulis G. Beck, the monotypic genus, Necranthus A.
Gilli endemic to Turkey, is allied with Orobanche L. Sect. Orobanche, the monotypic genus,
Platypholis Maxim, endemic to Bonin Is. of Japan, is far from Orobanche L. in relation and
should be regarded as a separate genus.
The 11 OTU’s, including all the sections of Orobanche L. and 7 genera of Orobanchaceae,
and 15 morphological characters were used in the numerical taxonomic treatment to test the
above-mentioned suggestions. After standardization of characters, the correlation matrices were
computerized. The correlation matrices were made to test the various clustering methods. At
last the UPGMA clustering method was chosen and its result is shown in a phenogram. The
result of numerical analysis is basically in accordance with the suggestions. 相似文献
5.
Chin Hui-Chen Chang Mei-Chen Ling Ping-Ping Ting Chih-Tsun Dou Fang-Ping 《植物分类学报:英文版》1985,23(1):11-18
The chromosome numbers of 5 tuberous sections of Chinese Dioscorea, including 23 species and varieties, are reported in the present paper as a continuation of the previous reports. They are all polyploids with the basic number x=10. On the basis of analysis of chromosome numbers of whole genus, the rhizomatous diploid species of Sect. Stenophora Uline are presumed to be primitive taxa, while the polyploids of chromosome numbers 40-142 are considered derived groups as a result of hybridization between their ancestral diploids followed by chromosome doubling. Sect. Lasiophyton Pr. et Burk., Sect. Opsophyton UIine, Sect. Shannicorea Pr. et Burk., Sect. Combilium Pr. et Burk. and Sect. EnantiophylIum Uline may be the advanced groups. The chromosomal evolution and geographical distribution suggest that the primitivediploid might have originated in Hengduan Mountains of Asia, an old highland. 相似文献
6.
本文论述了猪毛菜属系统分类的简史。依据该属的系统分类新资料,对我国猪毛菜属的分组系统作了进一步整理,将国产猪毛菜属植物归为6组5亚组。文中还讨论了该属的起源发生、迁移、分化以及地理分布等问题。 相似文献
7.
依据世界范围栝楼属植物种类的形态学、孢粉学、细胞学、系统发育研究资料,对栝楼属植物的系统演化和现代地理分布的形成进行了总结。栝楼组在栝楼属中处于原始地位,大苞组、叶苞组属于较进化类群,该属内的部分类群是在二倍体的水平上经过多倍化形成的。栝楼属在第三纪时期广布于欧洲、北美洲、亚洲、大洋洲,到第三纪晚期演化进程加快,南亚和中国西南山地逐步成为该属的起源中心与分化中心;受第四纪冰川期影响,该属在欧洲的种类逐渐消失,东亚成为该属的现代分布中心。栝楼属作为中国本地起源种,是中国植物区系中的重要组成部分。 相似文献
8.
桂樱属(Laurocerasus Tourn.ex Duh.)是蔷薇科李亚科的一个属。它是De Tournefort(Institutiones rei Herbariae 627.t.403.1700)以Prunus laurocerasus L.和P.lusitanica L.两种奠定基础,而至1755年由Duhmal代为正式发表而建立。自该属建立以后的二百多年来,各国植物学家对其分类位置各持不同观点。 相似文献
9.
Zhang Yu-Hua 《植物分类学报:英文版》1987,25(3):204-219
The genus Yinshania was established by Ma Yu-chuan and Zhao Yi-zhi in 1979,
when only one species, Y. albiflora Ma et Y. Z. Zhao, was discribed from Nei Monggol. In
the present paper the genus Yinshania is revised and four new species, two new varieties and
four new combinetions are reported. There are so far eight species and two varieties in total
in this genus.
Important morphological characters of the genus are analysed, which shows that the lateral
nectariferous glands positioned at lateral base of the brevistamens are triangularovoid; there are
dense minute pustules on the surface of valves, which is easily neglected because the pustules disappear or shrinked when dry; simple or furcate hairs are present in the most species, seldom absent;
the shape of pollen grains is relatively steady, elliptic or long-elliptic, with the polar view trifidcircular, the equatorial view elliptic or long elliptic, the aperture 3-colpate, exine reticular.
The type of genus Yinshania is changed. Cochlearia acutangula O. E. Schulz was published
in 1929, but Y. albiflora Ma et Y. Z. Zhao in 1979. They are the same species and a new combinetion, Y. acutangula (O. E. Schulz) Y. H. Zhang, is made. Thus, the type of genus Yinshania should be changed to Y. acutangula (O. E. Schulz) Y. H. Zhang.
Besides, He Ye-qi 6121 (paratype, PE), which is different from Y. acutangula var. albiflora, is separated from it and transferred the typical variety, Y. acutangula.
According to the characters of fruit shape the genus Yinshania is divided into two sections,
namely, Sect. Microcarpa and Sect. Yinshania, and then Sect. Yinshania is subdivided into two
series.
Sect. 1. Microcarpa. Silicles widely ovoid or subglobose, 1-2.2 mm long, 0.8-2.2 mm wide,
the ratio of length and width about 1.1.
Sect. 2. Yinshania. Silicles oblong, oblong-ovoid or long-lanceolate, ellipsoidal, 1.5-4.5 mm
long, 0.3-1.5 mm wide, the ratio of length and width about 2.5-3.3.
Ser. 1. Henryanae. Raches flexuose; plants densely hairy; leaves 3-5-foliolate, seldom
pinnatipartite or pinnatisect.
Ser. 2. Yinshania. Raches non flexuose; plants sparsely hairy; leaves pinnatisect or pinnatipartite.
The genus Yinshania is a genus endemic to China, with their range from eastern Xizang to
western Hubei from northern Guizhou to central Nei Monggol. The taxa are mostly of a small
area. Sect. Microcarpa is concentrated in Sichuan and southern Gansu; Sect. Yinshania is
spread from Xizang and Sichuan, nouthwards to Gansu, Ningxia, Shanxi, Hebei and Nei Monggol (Ser. Yinshania); and from Sichuan south-eastwards to Guizhou and Hebei (Ser. Henryanae). There are five species in Sichuan. The present paper conjectures that the distribution
centre of the genus is in the Hengduan Mountains and its adjacent areas. 相似文献
10.
After the genus Phlegmariurus (Herter)Holub was proposed by J. Holub 1964,
the repercussions are different, with some botanists accepting it, while others refusing. We
take it as a separate genus since the related species from China are distinctly different from
those of Huperzia Bernh. The plants of this genus in China are classified into three sections:
Sect. Huperzioides H. S. Kung et L. B. Zhang, sect. nov.; Sect. Carinaturus (Herter)H.
S. Kung et L. B. Zhang, comb. nov. and Sect. Phlegmariurus. A key to sections is given.
The taxonomy on the new section, Sect. Huperzioides, is presented. Thirteen species are reported in China, involving 4 new combinations: Ph. petiolatus (Clarke)H. S. Kung et L. B.
Zhang, Ph. cryptomerianus (Maxim.)Ching, Ph. ovatifolius (Ching)W. M. Chu, Ph.
nylamensis (Ching et S. K. Wu)H. S. Kung et L. B. Zhang; and 7 names are considered for
the first time as synonyms: Huperzia formosana Holub [ = Ph. taiwanensis Ching ], H.
austrosinica Ching [ = Ph. petiolatus ], Lycopodium mingchgense Ching [ = Ph.
mincheensis Ching ], Ph. mincheensis var. angustifolius C. Y. Ma [ = Ph. mincheensis ],
Ph. longyangensis C. Y. Ma [ = Ph. fordii ], Ph. nanus C. Y. Ma [ = Ph. fordii ], Ph.
yandongensis Ching et C. F. Zhang [ = Ph.fordii]. One new record in China is found: Ph.hamiltonii. 相似文献
11.
中国石杉属(狭义)小杉兰组的分类学研究 总被引:5,自引:0,他引:5
本文将石杉科石杉属(狭义)分为两组,即小杉兰组Sect.Huperzia和蛇足石杉组Sect.Serratae
(Rothm.)Holub,对小杉兰组的概念进行了修订并对国产有关种类进行了分类学研究。共记载国产小杉
兰组植物12种1变种,并包括1个新组合:Huperzia quasipolytrichoides(Hayata)Ching var. rectifolia
(J.F.Cheng)H.S.Kung et L.B.Zhang,2个新异名:H.hupehensis Ching和H.whangshanensisChing et P.C.Chiu. 相似文献
12.
Pu Fa-Ting 《植物分类学报:英文版》1991,29(5):385-393
Ligusticum is a highly specialized genus in the tribe Ammineae Koch of the
subfamily Apioideae. It is transitional between the tribe Ammineae Koch and the tribe
Peucedaneae DC., and shows a very close affinity to the genus Selinum.
In the present paper, the taxonomic history is reviewed; the external morphology, pollen
morphology and geographic distribution are analysed, and its evolutionary tendencies are
discussed. In addition, a key to the 34 species is provided, and economic uses reported in the
literature are summarized.
Ligusticum consists of over 60 species widely distributed in Eurasia and North America;
the genus is typically temperate. There are two principal distribution centers, one in the
Himalayas, including the Hengduan Mountains of western China, and the other in North
America. Thirty-four species occur in China, most of which are distributed in the alpine belt
of south-western China, with only a few species occurring in northern China. They usually
grow in alpine thicket meadows or in alpine meadows. Among them are 28 species endemic
to China, 4 of which are described as new in the present paper, i. e. L.yuayuanense,
L.litanense, L.filifolium, and L.yunnanense. L.elatum (Edgew.) C. B. Clarke, a species of
India, Afghanistan, and Pakistan, and L. thomsonii C.B.Clarke var. evolutior C. B. Clarke,
of India, Pakistan and Kashmir, are reported from China for the first time.
Some species are important in traditional Chinese medicine, for example, L. sinense
Oliv., L. sinense Oliv. cv. Chuanxiong, L. sinense Oliv. cv. Fuxiong, L. delavayi Franch.,
L. jeholense (Nakai et Kitagawa) Nakai et Kitagawa, L. tachiroei (Franch. et Sav.) Hiroe
et Constance, etc.
The genus Tilingia was established by Regel in 1858, based on Tilingia ajanensis. The
chief characters of the genus are distinct calyx teeth and carpels bearing a solitary vitta in
each furrow. However, these characters do not differentiate Tilingia from Ligusticum, so
that Tilingia was transferred to Ligusticum by Kozo-Poljansky in 1916. Tilingia tachiroei
(Franch. et Sav.) Kitagawa was transferred to Ligusticum by Hiroe et Constance in
1958. Shan et Sheh in “F1. Reip. Pop. Sin.” Tom. 55 supported the treatment by
Kozo-Poljansky and Hiroe and Constance
The genus Ligusticopsis was separated from Ligusticum by Leute in 1969, based on
the prominent calyx teeth of the former. Ligusticopsis included 14 species, all confined
to China. But this genus has not been accepted by any other botanists since its establishment.
The subdivision of Ligusticum in this paper is based mainly on the characters of
involucel bracteoles and mericarps, combined with the shape and aperture types of pollen
grains. The genus is divided into the following two sections.
Sect.1 Ligusticum, Bracteoles linear or lanceolate, entire; mericarps slightly
lateral-compressed to slightly dorsal-compressed; vittae solitary to numerous in each
furrow; leaf-segments ovate, lanceolate, or linear; pollen grains mainly rhomboidal or
ellipsoidal; apertures gonitreme.
Sect. 2 Pinnatibracteola Pu. Bracteoles 1-3-pinnatisect or 2-3-lobed at apex;
mericarps dorsal-compressed; vittae usually numerous in each furrow; leaf-segments
usually linear, rarely ovate or lanceolate; pollen grains rectangular,
elongate-rhomboidal, or equatorially constricted; apertures mainly peritreme, rarely gonitreme or intermediate. 相似文献
13.
Lu Sheng-Lien 《植物分类学报:英文版》1992,30(6):529-540
Some new taxa of the genus Festuca (Gramineae) are described
from China. They are Sect. Longiglumes S.L. Lu,Sect. Muticae S.L. Lu, Sect.
Sinensis S.L. Lu, Sect, Nitidulae S.L. Lu, and Festuca pubiglumis S.L. Lu, F.
longiglumis S. L. Lu, F.fascinata Keng, F. mutica S.L. Lu, F. sinensis Keng, F.
subalpina Chang et Skvort. ex S.L. Lu, F. chelungkingnica Chang et Skvort. exS.L. Lu. In addition, one new name F. taiwanensis S.L. Lu is included. 相似文献
14.
The present paper deals with the infrageneric classification, phylogeny and geographic distribution of the genus Lomatogonium.
A cladistic analysis was undertaken to establish the taxa and to evaluate the relationships between the taxa. The PAUP computer program was used in this analysis. The most parsimonious tree (Cladogram) of the rotate-corolla group of
subtribe Gentianinae shows that Lomatogonium is closely related to Lomatogoniopsis and Swertia, but distantly to Veratrilla. Among them, Swertia is more primitive than Lomatogonium and hence Sect. Swertia was selected as the outgroup to polarize the character states of ingroup (Lomatogonium). A data matrix of 29 charaters of Lomatogonium was made for constructing the cladogram. Two most parsimonious trees were formed one of which, with the lowest f value, was at last selected as a shortest tree. In this tree 18 species fall into three groups, i.e. Sect. Sarcorhizoma, Sect. Lomatogonium and Sect. Pleurogynella. The former comes at a lower level with more plesiomorphies while the latter at a higher level with
more apomorphies. Lomatogonium is distributed in the northern temperate zone. However, 16 species are centred in Asia and two extend to Europe, or further to the Arctic region, but none has been found from Africa, Australia and South erica. The analysis of distribution pattern of species shows that the Qinling-Hengduan Mountain region is both the frequence and diversity centers of Lomatogonium. From the cladogram of Lomatogonium (Fig. 5 ), L. perenne appears to occupy the most plesiomorphic node. This is an indication that it is the extant species closest to the ancestral form and it also implies that the ancestral species may reside in the habitat of this species (the Qinlin-Hengduan Mountain region). On the other hand, a umber of species of Swertia Sect. Swertia also occur in this region today, which indicates that the Qinlin-Hengduan Mountain region may well be the original center of Lomatogonium. From the distribution pattern of L. rotatum, it can be concluded that the time of the origin dates back at least before the Pliocene. After emergence, this genus had first developed and dispersed in the original center and adjacent region, then diverged into two lineages. One gave rise to the widespread species (northern temperate distribution species L.
carinthiacum and L. rotatum), and the other formed the Himalayan species.A taxonomic revision of the whole genus Lomatogonium is presented. In this paper, one new section (Sect. Sarcorhizoma), one new species (L. zhongdianense S. W. Liu et T. N. Ho) and one new variety (L. forrestii var. densiflorum S. W. Liu et T. N. Ho) are described. The key to the species is given. Type studies are made for all the taxa. 相似文献
15.
16.
Pan Jin-Tang 《植物分类学报:英文版》1988,26(2):120-129
In this paper the classification of the genus Bergenia Moench is provided, its
geographic distribution analysed, and the phylogeny also traced. Based on an analysis of
morphological characters such as leaves, ocreas, branches of inflorescences, Pedicels, hypanthium, sepals, and glandular indumentum, thi genus is divided into 3 sections: 1. Sect. Scopulosae J. T. Pan, sect. nov., 2. Sect. Bergnia, 3. Sect. Ciliatae (A. Boriss.) J. T. Pan, stat. nov.
The Sect. Scopulosae J. T. Pan may be considered as the primitive one, while Sect. Ciliatae
(A. Boriss.) J. T. Pan may be regarded as the advanced one, with Sect. Bergenia in between.
So far, the genus Bergenia Moench comprises 9 species in the total. Southeast Asia and
North Asia (south and east Siberia, USSR) each have only 1 species, West Asia (Afghanistan) has 2, Central Asia (Kirghizia-Tajikistan-Uzbekstan area, USSR) 3, South Asia 4 (Nepal
has 4, India, Pakistan and Kashmir area each has 3, Bhutan and Sikkim each has 2), East
Asia 6. In East Asia, Mongolia and Korea each have only 1 species, but China has 6 (including endemic species 2 and new species 1). Sichuan Province and Xizang Autonomous Region
each have 3, Yunnan Province 2, Shaanxi Province (Qinling Mountains) and Uygur Autonomous Region of Xinjiang each have only 1.
Thus the distribution centre of this genus should be in the region covering Sichuan, Yunnan and Xizang. Moreover, it is noteworthy that Bergenia scopulosa T.
P. Wang in Sect. Scopulosae seems to have retained primitive characters, for example, non-ciliate leaves and ocreas, glabrous pedicels, hypanthium and sepals, and
this primitive species is found in Qinling Mountains and Sichuan. According to the
distribution of the primitive species, the author suggests that the centre of origin of
this genus be in the region covering Qinling Mountains and Sichuan. 相似文献
17.
The genus Swertia is one of the large genera in Gentianaceae, including 154
species, 16 series and 11 sections. It is disjunctly distributed in Europe, Asia, Africa and N.
America, but entirely absent from Oceania and S. America.
According to Takhtajan’s (1978) regionalization of the world flora, Swertia is found in
14 regions. Eastern Asiatic region with 86 species, of which 58 are local endemics, 13 series
and 9 sections, ranks the first among all the regions. The highest concentration of the taxa
and endemics in Eastern Asiatic region occurs in SW China-Himalayan area (Sikang-Yunnan
P. , W. Sichuan, W. Yunnan-Guichou Plateau of China and NE. Burma, N. Burmense P. ,
E. Himalayan P. and Khasi-Manipur P. ). In this area there are 74 species (48 endemics),
12 series, and 9 sections; thus about half species of the world total, three quarters of series
and 82% of sections occur in this small area. Besides, the taxa at different evolutionary
stages in Swertia also survive here. It is an indication that SW. China-Himalayan area is a
major distribution centre of the genus Swertia. In addition, Sudan-Zambezian Region in
Africa, with 22 species, 4 series and 2 sections, is a second distribution centre.
The primitive type of the genus Swertia is Sect. Rugosa which consists of 2 series and
23 species. It is highly centred in the mountains of SW. China (Yunnan, Sichuan, Guizhou
and SE. Xizang) where 2 series and 16 species occur. Among them 15 species of Ser. Rugosae were considered as the most primitive groups in this genus. From our study, the outgroup of Swertia is the genus Latouchea Frahch. , which is distributed in Yunnan, Sichuan,
Guizhou, Hunan, Guangdong, Guangxi and Fujian. The two groups overlap in distribution
in SW. China. According to the principle of common origin, the ancestor of two genera ap peared most probably in this overlapping area. It was inferred that SW. China Was the birth-place of the genus Swertia.
Four sections of Swertia have different disjunct distribution patterns: Sect. Ophelia is of
Tropic Asia, Africa and Madagascar disjunct distribution; sect. Swertia is of north temperate distribution; sect. Spinosisemina is in Tropical Asia (Trop. India to S. China and Philipines); sect. Platynema also is in Tropical Asia (Java, Sumatra, Himalayas to SW. China).
These disjunct patterns indicate that the Swertia floras between the continents or between
continent and islands have a connection with each other. From paleogeographical analysis,
Swertia plants dispersed to Madagascar before the Late Cretaceous, to SE. Asian Islands in
the Pleistocene, to North America in the Miocene. The distribution of Swertia in Madagascar might be later than that in Asia. Therefore the origin time of the genus Swertia was at
least not later than the Late Cretaceous, and might be back to the Mid-Cretaceous.
The genus Swertia first fully developed and differentiated, forming some taxa at different evolutionary stages (Rugosa, Swertia, Poephila, Ophelia and Platynema etc. ) in the original area, and these taxa quickly dispersed in certain directions during the Late Cretaceous-Middle Tertiary when the global climate was warm and no much change. There seem
to be three main dispersal routes from the origin area to different continents; (1) The westward route i. e. from SW. China, along the Himalayas area to Kashmir, Pakistan,
Afghanistan and Iran, and then southwestwards into Africa throuth Arabia. Four sections
(Poephila, Macranthos, Kingdon-Wardia and Ophelia) took this dispersal route. Most
species of sect. Ophelia dispersed along this route, but a few along southern route and north
ern route. Sect. Ophelia greatly differentiated in Africa and the African endemic sectionSect. Montana was derived from it. The two sections form there a second distribution center
of Swertia. (2) The southward route, i. e. towards S. India through the Himalayas, and
towards SE. Asian islands through C. and S. China, Indo-China. Along this dispersal route
sect. Platynema, Sect. Spinosisemina and a few species of Sect. Ophelia dispersed; (3) The
northward rout, i. e. northwards across N. China, C. Asia to a high latitude of Euasia,
and also through E. Asia into N. America. The following groups took this route: sect. Rugosa, sect. Swertia, sect. Frasera, sect. Heteranthos and sect. Ophelia ser. Dichotomae.
Therefore, it seems that the genus Swertia originated in SW. China and then dispersed
from there to N. and S. Asia, Africa, Europe and North America and formed the moderndistribution pattern of this genus. 相似文献
18.
Li Hen 《植物分类学报:英文版》1981,19(1):29-42
The genus Ottelia is one of the great genera of Hydrocharidaceae. About 25 species distributed in the Palaeotropics, extending from Africa through India and SE.
Asia to Korea and Japan, Australia and New Caledonia, 1 species in Brazil; centres of
specific devolopment are found in Central Africa and SE Asia.
The present study is mainly based on the materials collected during the field explorations in the lakes of Yunnan and observations on the structure of the spathe and
flowers, the variation of leaf of the plants cultivated in Kunming Bot. Garden.
Instead of the wings of the spathe used by Dandy, by the characters such as uni-or
bisexual flowers, this genus is divided into two subgenera, which by the number of the
flowers in spathe and the number of the carpus in ovary again subdivided into 4
sections. They are as the following:
A. Subg. Ottelia. Flowers bisexual.
Sect. 1. Ottelia. Spathe with 1 flower; ovary with 6(—9) carpus.
Sect. 2. Oligolobos (Gagnep.) Dandy. Spathe with many flowers; ovary with 3 carpus.
B. Subg. Boottia (Wall.) Dandy. Flowers unisexual; the male spathe with 1-many
flowers, the female spathe with many flowers.
Sect. 3. Boottia. The male spathe with 1 flower; ovary with 9(—15) carpus.
Sect. 4. Xystrolobos (Gagnep.) H. Li. The female spathe with (2-) many flowers; ovary with 3 or 9 carpus.
The Chinense species of ottelia is in great need for revision. All of the species in
China previousely described under Ottelia Pers, Boottia Wall., Oligolobos Gagnep, and
Xystrolobos Gagen. are here combined into 3 species. They are O. alismoides, O. cordata, O. acuminata with 4 variaties.
After a study of the geographic distribution and infer relation-ships among the
floristic elements it has been proved that Ottelia is certainly an ancient genus, and the
primitive types came into being and widely dispersed before the separation of Laurasia
from Gondwana.
During a considerable period of time the elements of the genus Ottelia in freshwater environment of different continents have been separately differentiated and evolved into more or less derived types. The structure of flowers in all of the asian species
shows the following evolutionary tendenoes: 1. In this genus the plants with unisexual
flowers have evolved from plants with bisexual flower; 2. In the groups with bisexual
or unisexual flowers the number of stamens and styles reduced to 3-merous, but the
number of flowers in spathe increased. So that the subgenus Ottelia is more primitive
than the subgenus Bottia; While in the subgenus Ottelia O. alismoides is a more primitive than O. balansae and in the subgenus Boottia O. cordata is the most primitive, butO. alata seems to be the most advanced. 相似文献
19.
中国产瓦韦属植物叶柄与根状茎的比较解剖研究 总被引:3,自引:0,他引:3
详细观察了已发表的60种瓦韦属植物叶柄和根状茎的横切面。瓦韦属植物叶柄维管束条数最多7条,最少2条,其中2个较粗,其余较细,排成一字型、三角型、四角型、半轮型等。根状茎上的维管束条数最少5条,最多16条,属于网状中柱,维管束不规则环形排列,夏绿种类厚壁组织较少或没有,常绿种类厚壁组织较多。叶柄与根状茎的研究对瓦韦属组的划分和种的确立有重要的参考价值。参考这些特征,瓦韦属相应地划分成六个组,即:大叶瓦韦组、扭瓦韦组、瓦韦组、革质叶瓦韦组、纸质叶瓦韦组、网眼瓦韦组。一些种类相应地进行了合并。 相似文献
20.
中国沙拐枣属植物的数值分类研究 总被引:7,自引:0,他引:7
选择了中国19种沙拐枣属(CalligonumL.)植物,共测定及引用了35个形态分类指标,应用单因素方差分析(MANOVA)和主成分分析(PCA),分别对形态因子进行了单元和多元分析。结果表明,所有的种间形态指标均差异显著,冠幅(BC),木质枝枝节长度(LKWB),果实直径(DF),雄蕊长度(SL),同化枝枝节长度(LKAS)和同化枝化枝角度(ARAS)指标在沙拐枣属植物的数值分类上,具有很强的差异性分析意义。依据平方欧氏距离,应用类平均法(UPGMA)将19种沙拐枣植物聚为5类,系统聚类结论与主成分分析的三维排序结果基本一致,与传统的形态分类结果有一定的差异。 相似文献