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1.
方振富 《中国科学院研究生院学报》1987,25(4):307-313
1. The distribution of Salix species among the continents. There are about
526 species of Salix in the world, most of which are distributed in the Northern Hemisphere
with only a few species in the Southern Hemisphere. In Asia, there are about 375 species, mak-
ing up 71.29 percent of the total in the world, including 328 endemics; in Europe, about 114
species, 21.67 percent with 73 endemics; in North America, about 91 species, 17.3 percent with
71 endemics; in Africa, about 8 species, 1.5 percent, with 6 endemics. Only one species occurs
in South America. Asia, Europe and North America have 8 species in common (excluding 4
cultivated species). There are 34 common species between Asia and Europe, 14 both between
Europe and North America and between Asia and North America, 2 between Asia and Africa.
Acording to the Continental Drift Theory, the natural circumstances which promoted speciation
and protected newly originated and old species were created by the orogenic movement of the
Himalayas in the middle and late Tertiary. Besides, the air temperature was a little higher in
Asia than in Europe and North America (except its west part) and the dominant glaciers were
mountainous in Asia during the glacial epoch in the Quaternary Period. Then willows of Eu-
rope moved southwards to Asia. During the interglacial period they moved in opposite direc-
tion. Such a to-and-fro willow migration between Asia and Europe and between and North
America occurred so often that it resulted in the diversity of willow species in Asia. Those
species of willows common among the continents belong to the Arctic flora.
2. The multistaminal willows are of the primitive group in Salix. Asia has 28 species of
multistaminal willows, but Europe has only one which is also found in Asia. These 28 species
are divided into two groups, “northern type” and “southern type”, according to morphology of
the ovary. The boundary between the two forms in distribution is at 40°N. The multistami-
nal willows from south Asia, Africa and South America are very similar to each other and
may have mutually communicated between these continents in the Middle or Late Cretaceous
Period. The southern type willows in south Asia are similar to the North American multista-
minal willows but a few species. The Asian southern type willows spreaded all over the conti-
nents of Europe, Asia and North America through the communication between them before the
Quaternany Period. Nevertheless, it is possible that the willows growing in North America
immigranted through the middle America from South America. The Asian northern type mul-
tistaminal willows may have originated during the ice period.
The multistaminal willows are more closed to populars in features of sexual organs. They
are more primitive than the willows with 1-3 stamens and the most primitive ones in the ge-
nus.
3. The center of origin and development of willows Based on the above discussion it is re-
asonable to say that the region between 20°-40°N in East Asia is the center of the origin and
differentiation of multistaminal willows. It covers Southern and Southwestern China and nor-
thern Indo-China Pennisula. 相似文献
2.
论胡桃科植物的地理分布 总被引:1,自引:0,他引:1
路安民 《中国科学院研究生院学报》1982,20(3):257-274
The present paper aims to discuss the geog raphical distribution of the Juglandaceae
on the basis of unity of the phylogeny and the process of dispersal in the plants.
The paper is divided into the following three parts:
1. The systematic positions and the distribution patterns of nine living genera in
the family Juglandaceae (namely, Engelhardia, Oreomunnea, Alfaroa, Pterocarya, Cyclo-
carya, Juglans, Carya, Annamocarya and Platycarya) are briefly discussed. The evolu-
tional relationships between the different genera of the Juglandaceae are elucidated. The
fossil distribution and the geological date of the plant groups are reviewed. Through
the analysis for the geographical distribution of the Juglandaceous genera, the distribu-
tion patterns may be divided as follows:
A. The tropical distribution pattern
a. The genera of tropical Asia distribution: Engelhardia, Annamocarya.
b. The genera of tropical Central America distribution: Oreomunnea, Alfaroa.
B. The temperate distribution pattern
c. The genus of disjunct distribution between Western Asia and Eastern Asia:
Pterocarya.
d. The genus of disjunct distribution between Eurasia and America: Juglans.
e. The genus of disjunct distribution between Eastern Asia and North America:
Carya.
f. The genera whose distribution is confined to Eastern Asia: Cyclocarya, Platy-
carya.
2. The distribution of species
According to Takhtajan’s view point of phytochoria, the number of species in every
region are counted. It has shown clearily that the Eastern Asian Region and the Coti-
nental South-east Asian Region are most abundant in number of genera and species. Of
the 71 living species, 53 are regional endemic elements, namely 74.6% of the total species.
The author is of the opinion that most endemic species in Eurasia are of old endemic
nature and in America of new endimic nature. There are now 7 genera and 28 species
in China, whose south-western and central parts are most abundant in species, with Pro-
vince Yunnan being richest in genera and species.
3. Discussions of the distribution patterns of the Juglandaceae
A. The centre of floristic region
B. The centre of floristic regions is determined by the following two principles: a.
A large number of species concentrate in a district, namely the centre of the majority;
b. Species of a district can reflect the main stages of the systematic evolution of the
Juglandaceae, namely the centre of diversity. It has shown clearly that the southern
part of Eastern Asian region and the northern part of Continental South-east Asian
Region (i.c. Southern China and Northern Indo-China) are the main distribution centre
of the Juglandaceae, while the southern part of Sonora Region and Caribbean Region
(i.c. South-western U.S.A., Mexico and Central America) are the secondary distribution
centre.
As far as fossil records goes, it has shown that in Tertiary period the Juglanda-
ceae were widely distributed in northern Eurasia and North America, growing not only
in Europe and the Caucasus but also as far as in Greenland and Alaska. It may be
considered that the Juglandaceae might be originated from Laurasia. According to
the analysis of distribution pattern for living primitive genus, for example, Engelhar-
dia, South-western China and Northern Indo-China may be the birthplace of the most
primitive Juglandaceous plants. It also can be seen that the primitive genera and the
primitive sections of every genus in the Juglandaceae have mostly distributed in the
tropics or subtropics. At the same time, according to the analysis of morphological cha-
racters, such as naked buds in the primitive taxa of this family, it is considered that
this character has relationship with the living conditions of their ancestors. All the
evidence seems to show that the Juglandaceae are of forest origin in the tropical moun-
tains having seasonal drying period.
B. The time of the origin
The geological times of fossil records are analyzed. It is concluded that the origin
of the Juglandaceae dates back at least as early as the Cretaceous period.
C. The routes of despersal
After the emergence of the Juglandaceous plant on earth, it had first developed and
dispersed in Southern China and Indo-China. Under conditions of the stable tempera-
ture and humidity in North Hemisphere during the period of its origin and development,
the Juglandaceous plants had rapidly developed and distributed in Eurasia and dis-
persed to North America by two routes: Europe-Greenland-North America route and
Asia-Bering Land-bridge-North America route. From Central America it later reached
South America.
D. The formaation of the modern distribution pattern and reasons for this forma-
tion.
According to the fossil records, the formation of two disjunct areas was not due to
the origin of synchronous development, nor to the parallel evolution in the two con-
tinents of Eurasia and America, nor can it be interpreted as due to result of transmis-
sive function. The modern distribution pattern has developed as a result of the tectonic
movement and of the climatic change after the Tertiary period. Because of the con-
tinental drift, the Eurasian Continent was separated from the North American Conti-
nent, it had formed a disjunction between Eurasia and North America. Especially, under
the glaciation during the Late Tertiary and Quaternary Periods, the continents in Eu-
rasia and North America were covered by ice sheet with the exception of “plant refuges”, most plants in the area were destroyed, but the southern part of Eastern Asia
remained practically intact and most of the plants including the Juglandaceae were
preserved from destruction by ice and thence became a main centre of survival in the
North Hemisphere, likewise, there is another centre of survival in the same latitude in
North America and Central America.
E. Finally, the probable evolutionary relationships of the genera of the Juglanda-ceae is presented by the dendrogram in the text. 相似文献
3.
木兰科分类系统的初步研究 总被引:10,自引:0,他引:10
刘玉壶 《中国科学院研究生院学报》1984,22(2):89-109
A new system of classification of Magnoliaceae proposed. This paper deals mainly with taxonomy and phytogeography of the family Magnoliaceae on the basis of external morphology, wood anatomy and palynology. Different authors have had different ideas about the delimitation of genera of this family, their controversy being carried on through more than one hundred years (Table I). Since I have been engaged
in the work of the Flora Reipublicae Popularis Sinicae, I have accumulated a considerable amount of information and material and have investigated the living plants at their natural localities, which enable me to find out the evolutionary tendencies and primitive morphological characters of various genera of the family. According to the evolutionary tendencies of the characters and the geographical distribution of this family I propose a
new system by dividing it into two subfamilies, Magnolioideae and Liriodendroideae Law (1979), two tribes, Magnolieae and Michelieae Law, four subtribes, Manglietiinae Law, Magnoliinae, Elmerrilliinae Law and Micheliinae, and fifteen genera (Fig. 1 ), a system which is different from those by J. D. Dandy (1964-1974) and the other authors.
The recent distribution and possible survival centre of Magnoliaceae. The members of Magnoliaceae are distributed chiefly in temperate and tropical zones of the Northern Hemisphere, ——Southeast Asia and southeast North America, but a few genera and species also occur in the Malay Archipelago and Brazil of the Southern Hemisphere. Forty species of 4 genera occur in America, among which one genus (Dugendiodendron) is endemic to the continent, while about 200 species of 14 genera occur in Southeast Asia, of which 12 genera are endemic. In China there are about 110 species of 11 genera which mostly occur in Guangxi, Guangdong and Yunnan; 58 species and more than 9 genera occur in the mountainous districts of Yunnan. Moreover, one genus
(Manglietiastrum Law, 1979) and 19 species are endemic to this region. The family in discussion is much limited to or interruptedly distributed in the mountainous regions of Guangxi, Guangdong and Yunnan. The regions are found to have a great abundance of species, and the members of the relatively primitive taxa are also much more there than in the other regions of the world.
The major genera, Manglietia, Magnolia and Michelia, possess 160 out of a total of 240 species in the whole family. Talauma has 40 species, while the other eleven genera each contain only 2 to 7 species, even with one monotypic genus. These three major genera are sufficient for indicating the evolutionary tendency and geographical distribution of Magnoliaceae. It is worthwhile discussing their morphological characters and
distributional patterns as follows:
The members of Manglietia are all evergreen trees, with flowers terminal, anthers dehiscing introrsely, filaments very short and flat, ovules 4 or more per carpel. This is considered as the most primitive genus in subtribe Manglietiinae. Eighteen out of a total of 35 species of the genus are distributed in the western, southwest to southeast Yunnan. Very primitive species, such as Manglietia hookeri, M. insignis and M. mega-
phylla, M. grandis, also occur in this region. They are distributed from Yunnan eastwards to Zhejiang and Fujian through central China, south China, with only one species (Manglietia microtricha) of the genus westwards to Xizang. There are several species distributing southwards from northeast India to the Malay Archipelago (Fig. 7).
The members of Magnolia are evergreen and deciduous trees or shrubs, with flowers terminal, anthers dehiscing introrsely or laterally, ovules 2 per carpel, stipule adnate to the petiole. The genus Magnolia is the most primitive in the subtribe Magnoliinae and is the largest genus of the family Magnoliaceae. Its deciduous species are distributed from Yunnan north-eastwards to Korea and Japan (Kurile N. 46’) through Central
China, North China and westwards to Burma, the eastern Himalayas and northeast
India. The evergreen species are distributed from northeast Yunnan (China) to the
Malay Archipelago. In China there are 23 species, of which 15 seem to be very primi-
tive, e.g. Magnolia henryi, M. delavayi, M. officinalis and M. rostrata, which occur in
Guangxi, Guangdong and Yunnan.
The members of Michelia are evergreen trees or shrubs, with flowers axillary, an-
thers dehiscing laterally or sublaterally, gynoecium stipitate, carpels numerous or few.
Michelia is considered to be the most primitive in the subtribe Micheliinae, and is to
the second largest genus of the family. About 23 out of a total of 50 species of this
genus are very primitive, e.g. Michelia sphaerantha, M. lacei, M. champaca, and M.
flavidiflora, which occur in Guangdong, Guangxi and Yunnan (the distributional center
of the family under discussion) and extend eastwards to Taiwan of China, southern
Japan through central China, southwards to the Malay Archipelago through Indo-China.
westwards to Xizang of China, and south-westwards to India and Sri Lanka (Fig. 7).
The members of Magnoliaceae are concentrated in Guangxi, Guangdong and Yunnan
and radiate from there. The farther away from the centre, the less members we are
able to find, but the more advanced they are in morphology. In this old geographical
centre there are more primitive species, more endemics and more monotypic genera.
Thus it is reasonable to assume that the region of Guangxi, Guangdong and Yunnan,
China, is not only the centre of recent distribution, but also the chief survival centreof Magnoliaceae in the world. 相似文献
4.
Xizang (Tibet) is rich in Leguminosae flora, comprising 41 genera and 254 species
so far known, exclusive of the commonly cultivated taxa (including 11 genera and 16
species). There are 4 endemic genera (with 8 species), 10 temperate genera (with 175
species) and 19 tropical genera (with 46 species) as well as the representatives of those
genera whose distribution centers are in East Asia-North America, Mediterranean
and Central Asia.
1. There are altogether 4 endemic genera of Leguminosae in this region. Accord-
ing to their morphological characters, systematic position and geographical distribution,
it would appear that Salweenia and Piptanthus are Tertiary paleo-endemics, while
Straceya and Cochlianths are neo-endemics. Salweenia and Piptanthus may be some
of more primitive members in the subfamily Papilionasae and their allies are largely
distributed in the southern Hemisphere. The other two genera might have been derived
from the northern temperate genus Hedysarum and the East Asian-North American
genus Apios respectively, because of their morphological resemblance. They probably
came into existanc during the uplifting of the Himalayas.
2. An analysis of temperate genera
There are twelve temperate genera of Leguminosae in the region, of which the
more important elements in composition of flora, is Astragalus, Oxytropis and Cara-
gana.
Astragalus is a cosmopolitan genus comprising 2000 species, with its center
distribution in Central Asia. 250 species, are from China so far known, in alpine zone of
Southwest and Northwest, with 70 species extending farther to the Himalayas and
Xizang Plateau.
Among them, there are 7 species (10%) common to Central Asia, 12 species (15.7%)
to Southwest China and 40 species (60%) are endemic, it indicates that the differentia-
tion of the species of the genus in the region is very active, especially in the subgenus
Pogonophace with beards in stigma. 27 species amounting to 78.5% of the total species of
the subgenus, are distributed in this region. The species in the region mainly occur in
alpine zone between altitude of 3500—300 m. above sea-level. They have developed into
a member of representative of arid and cold alpine regions.
The endemic species of Astragalus in Xizang might be formed by specialization of
the alien and native elements. It will be proved by a series of horizontal and vertical vicarism of endemic species. For example, Astragalus bomiensis and A. englerianus are
horizontal and vertical vicarism species, the former being distributed in southeast part
of Xizang and the latter in Yunnan; also A. arnoldii and A. chomutovii, the former
being an endemic on Xizang Plateau and latter in Central Asia.
The genus Oxytropis comprises 300 species which are mainly distributed in the
north temperate zone. About 100 species are from China so far known, with 40 species
extending to Himalayas and Xizang Plateau. The distribution, formation and differ-
entiation of the genus in this region are resembled to Astragalus. These two genera are
usually growing together, composing the main accompanying elements of alpine mea-
dow and steppe.
Caragana is an endemic genus in Eurasian temperate zone and one of constructive
elements of alpine bush-wood. About 100 species are from China, with 16 species in Xi-
zang. According to the elements of composition, 4 species are common to Inner Mon-
golia and Kausu, 4 species to Southwest of China, the others are endemic. This not only
indicates that the species of Caragana in Xizang is closely related to those species of
above mentioned regions, but the differentiation of the genus in the region is obviously
effected by the uplifting of Himalayas, thus leading to the formations of endemic species
reaching up to 50%.
3. An Analysis of Tropical Genera
There are 19 tropical genera in the region. They concentrate in southeast of Xizang
and southern flank of the Himalayas. All of them but Indigofera and Desmodium are
represented by a few species, especially the endemic species. Thus, it can be seen that
they are less differentiated than the temperate genera.
However, the genus Desmodium which extends from tropical southeast and northeast
Asia to Mexio is more active in differentiation than the other genera. According to Oha-
Shi,s system about the genus in 1973, the species of Desmodium distributed in Sino-Hima-
laya region mostly belong to the subgenus Dollinera and subgenus Podocarpium. The
subgenus Dollinera concentrates in both Sino-Himalaya region and Indo-China with 14
species, of which 7 species are endemic in Sino-Himalaya. They are closely related to
species of Indo-China, southern Yunnan and Assam and shows tha tthey have close con-
nections in origin and that the former might be derived from the latter.
Another subgenus extending from subtropical to temperate zone is Podocarpium.
Five out of the total eight species belonging to the subgenus are distributed in Sino-
Himalaya and three of them are endemic.
An investigation on interspecific evolutionary relationship and geographic distribu-
tion of the subgenus shows that the primary center of differentiation of Podocarpium
is in the Sino-Himalaya region.
Finally, our survey shows that owing to the uplifting of the Himalayas which has
brought about complicated geographic and climatic situations, the favorable conditions
have been provided not only for the formation of the species but also for the genus in cer-tain degree. 相似文献
5.
我国悬钩子属植物的研究 总被引:1,自引:0,他引:1
陆玲娣 《中国科学院研究生院学报》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 axill-
ary 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, dru-
plets adhering to the receptacles and with high chromosome numbers (2n = 56).
Basing upon the evolutionary tendency of morphological features, chromosome nu-
mbers 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 im-
portant 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 south-
western parts of China, namely Yunnan, Sichuan and Guizhou (tab. 3. 4.). It is in-
teresting to note that the centre of distribution of Rubus in China ranges From north-
western 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 distribu-
tion and differentiation of Rubus in China, but it may also be the center of origin ofthis genus. 相似文献
6.
陈心启 《中国科学院研究生院学报》1981,19(3):323-329
Acanthochlamydoideae, a new subfamily of Amaryllidaceae, is proposed in the pre-
sent paper, based upon the monotypic genus Acanthochlamys which was detected by
the writer in 1979 and named Didymocolpus as a new genus but was preceded by P. C.
Kao in 1980 under the former name. The genus is indeed of great morphological in-
terest. It has semicylindric leaves with a deep furrow on the ventral and dorsal sides
respectively. The lower part of the leaf is connate with, or adnate to, the lower mid-
rib of a rather large and membranous vagina . Such a feature, as far as we know, is
very rare in the monocotyledons.
The flower resembles that of Amaryllidaceae in having inferior ovary, six stamens
and corolla-like perianth with a rather long tube. But it is quite different in other
characters, such as head-like cyme, leaf-like bracts and bisulcate leaves, which all are
foreign to any taxon known in the Amaryllidaceae. On the other hand, it bears some
resemblance particularly in habit and inflorescence to Campynemanthe of the Hy-
poxidaceae, and also to Borya and Bartlingia of the Liliaceae (in the tribe John-
sonieae), but differs in its long perianth-tube and curious leaf structure. It is highly
probable that the resemblance between them is only superficial and not indicative of
direct or close relationship.
This is no doubt a very curious plant of which we still know incompletely, and
for which an appropriate place in the monocotyledons has not yet been found. Con-
sidering its floral characters, however, it seems safe for the present to place it as a
separate subfamily in the Amaryllidaceae and is juxtaposed with the Ixiolirioideae
and Amaryllidoideae, the only two subfamilies of Amaryllidaceae according to H. Mel-
chior (1964), and, of course, to either of them it is not directly related. Its true affinity
remains problematic.
The only species, Acanthochlamys bracteata, is found in Mar-er-kan (102°12'N,
31°47'E), Qian-ning (101°30'N, 30°33'E), Xiang-cheng (99°39'N, 28°54'E) and Dau
cheng (100°10'N, 29°03'E) in western Sichuan of southwest China, in open bushland
or grassland at an altitude between 2700—3500 meters. Its geographical distribution is
mapped and its morphological details are illustrated to facilitate its identification.
相似文献
7.
1) The Compositae in Tibet so far known comprise 508 species and 88 genera,
which nearly amounts to one fourth of the total number of genera and one third of the
total number of species of Compositae in all China, if the number of 2290 species and 220
genera have respectively been counted in all China. In Tibet there are all tribes of Com-
positae known in China, and surprisingly, the large tribes in Tibetan Compositae are
also large ones in all China and the small tribes in Tibet are also small ones in all China.
Generally speaking, the large genera in Tibet are also large ones in all China and the
small genera in Tibet are likewise small ones in all China. In this sense it is reasonable to
say that the Compositae flora of Tibet is an epitome of the Compositae flora of all China.
In the Compositae flora of Tibet, there are only 5 large genera each containing 30
species or more. They are Aster, Artemisia, Senecio, Saussurea and Cremanthodium. And
5 genera each containing 10—29 species. They are Erigeron, Anaphalis, Leontopodium,
Ajania, Ligularia and Taraxacum. In addition, there are 77 small genera, namely 87%
of the total of Compositae genera in Tibet, each comprising 1—9 species, such as Aja-niopsis, Cavea and Vernonia, etc.
2) The constituents of Compositae flora in Tibet is very closely related to those of
Sichuan-Yunnan provinces with 59 genera and 250 species in common. Such a situation
is evidently brought about by the geographycal proximity in which the Hengtuang Shan
Range links southeastern and eastern Tibet with northern and northwestern Sichuan-
Ynnnan. With India the Tibetan Compositae have 59 genera and 132 species in common,
also showing close floristic relationships between the two regions. Apparently the floris-
tic exchange of Compositae between Tibet and India is realized by way of the mountain
range of the Himalayas. The mountain range of the Himalayas, including the parallel
ranges, plays a important role as a bridge hereby some members of the Compositae of
western or northern Central Asia and of the northern Africa or of western Asia have
migrated eastwards or southeastwards as far as the southern part of Fibet and northern
part of India, or hereby some Compositae plants of eastern and southeastern Asia or
Asia Media have migrated northwestwards as the northern part of Central Asia.
Some of the species and genera in common to both Tibet and Sinjiang indicate that
this weak floristical relationship between these regions is principally realized through two
migration routes: one migration route is by way of the Himalayas including the parallel
ranges to Pamir Plataeu and Tien Shan, or vice versa. The other migration route is by
way of northern Sinjiang to Mongolia, eastern Inner Mongolia, southwards to Gansu,
Qinghai (or western Sichuan), eastern Tibet up to the Himalayas, or vice versa.
However, Tibet is not entirely situated at a migration crossroad of the floral ele-
ments. An ample amount of the data shows that Compositae flora have a particular
capability of development in Tibet. of the total number of species of Tibetan Com-
positae, 102 species and 1 genus (Ajaniopsis Shih) are endemic. Besides, 8 genera are re-
gional endemics with their range extending to its neighbourhood. The higher percentage
of endemics at specific level than at generic in Tibetan Compositae may be a result of
active speciation in response to the new enviromental conditions created by the uplifting
of the Himalayas. The flora in Tibetan Plateau as a whole appears to be of a younger
age.
3) The uprising of the Himalayas and of the Tibetan Plateau accompanied by the
ultraviolet ray radiation, the microthermal climate and the high wind pressure has, no
doubt, played a profound influence upon the speciation of the native elements of Tibetan
Compositae. The recent speciation is the main trend in the development of the Com-positae flora native in Tibet in the wake of upheaval of the plateau. 相似文献
8.
张志耘 《中国科学院研究生院学报》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
9.
10.
11.
Paphiopedilum malipoense S. C. Chen et Tsi is a very interesting new species with its flower similar to that of Cypripedium, especially section Cypripedium. It belongs
to subgenus Brachypetalum, the most primitive group of Paphiopedilum, but differs from
its allied species in hgniva elliptic-lanceolate sepal with cuspidately acuminate apex, rather
narrow petals and horizontal lip, which are of common occurrence in many cypripediums, but
very rare in paphiopedilums. Apparently, this is an intermediate form, or a link, between
Paphiopedilum and Cypripedium, but it does not seem to arise from hybridization between
them, because no Cypripedium has been found wherever Paphiopedilum occurs.
The new species is distributed in southeastern Yunnan of China. In this area, as well
as in river valleys of western Yunnan or the Hengduan Mountains, there have been four
species of the same genus reported before. As we know, the Hengduan Mountains and their
adjacent areas are rich in Cypripedium. The differentiation of the genus there is remarka-
ble. All five sections it contains occur there and three of them are quite distinctive. For
example, the general appearance of the section Bracleosa is dissimilar to that of any other
cypripediums, but closely resembles that of Listera. It appears that the difference between
sect. Bracteosa of Cypripedium and sect. Brachypetalum of Paphiopedilum is not neces-
sarily wider than that between sect. Bracteosa and sect. Cypripedium of the same genus.
Apparently, it is reasonable to consider Paphiopedilum to be an evolutional branch of Cy-
pripedium extending into tropical area, with its primitive group (subgenus Brachypetalum)
still remaining in its northern fringe area. This primitive subgenus has eight species, dis-
tributed from western Yunnan to the Malay Peninsula. Five of them, including the inter-
mediate and primitive form published here, are found in the hilly land of southeastern Yun-
nan and the river valleys of western Yunnan. All these facts suggest its area of origin: the
river valleys of the Hengduan Mountains and the lower hilly land contiguous to the southof them. 相似文献
12.
海菜花属的分类、地理分布和系统发育 总被引:1,自引:0,他引:1
李恒 《中国科学院研究生院学报》1981,19(1):29-42
The genus Ottelia is one of the great genera of Hydrocharidaceae. About 25 spe-
cies 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 ex-
plorations 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 car-
pus.
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 flow-
ers; 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. cor-
data, 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 fresh-
water environment of different continents have been separately differentiated and evolv-
ed 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 primi-
tive 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
13.
新种墨脱毛兰可能是足茎毛兰的“异常整齐花”型。 “异常整齐花”现象在兰科中时
有所见,在不同分类群中情况各异,至今尚未见系统的研究。本文认为辐射对称花被是兰科的
正常特征之一,主要见于原始的种类和少数进化的种类,也不同程度地存在于“异常整齐花”实
体中。具辐射对称花被的兰科植物大多数不是“异常整齐花”型,判断时要参酌其他特点,持慎
重态度。兰科“异常整齐花”有两种情况,一是异常型,亦即正常植株中仅偶见“异常整齐花”,
或同一个种可同时产生“异常整齐花”植株与正常植株,两者并存。另一种情况是正常型,亦即
只产生“异常整齐花”,而无正常的两侧对称花。后者意味着在进化过程中的一种飞跃,即形成
了新植物。对此最好作为独立的种处理,特别是在它的来源还不清楚的情况下更是如此。目
前所认为的一些所谓“异常整齐花”实体,大都是推测而已,其中有些或许在将来会被证明为正 常的、原始的植物。 相似文献