Table of Contents

10 November 1996, Volume 34 Issue 6
    Research Articles
  • Liang Han-xing, Pan Kai-yu, Chen Zhi-duan
    J Syst Evol. 1996, 34(6): 565-568.
    In the present study, floral organogenesis of Saururus chinensis was observed and compared with that of S. cernuus. The two species share essentially similar patterns of floral initiation and stamen development. Their inflorescence produces “common primordial” in acropetal succession on the flanks of the inflorescence meristem. Each primordium bifurcates transversely to form a floral apex above and a bract primordium below. Six stamens arise in three pairs at the floral apex. The median sagittal pair arises first,the lateral distal pair second, and the lateral proximal pair arises last. On the contrary, the initiation of carpels is quite different from each other. In S. cernuus, the median sagittal pair arises first,and the lateral pair next. In S. chinensis, however, the lateral pair arises first, and the median sagittal pair second. The present study also made a brief generalization using the data obtained from different fields on the relationship of the two species in the genus Saururus, which are disjunctly distributed between eastern Asia and North America.
  • Ren Yi, Hu Zheng-hai
    J Syst Evol. 1996, 34(6): 569-576.
    The morphology of the dichotomous venation,anastomoses and blind veins in the venation of the leaf of Kingdonia uniflora were studied in the present work. The laminan 5-divided. There are three veins at the base of the lamina,among which the middle one enters the base of the middle segment,and each lateral one dichotomyzes into two daughter veins. Each daughter vein enters the base of the lateral segments.The veins at the base of the segments dichotomize repeatedly 5~6 times forming the veins of different orders.Each vein of a particular order and its branches corresponde a particular lobe of the same order, and the ultimate vein terminates in the middle part of the umbo at the apex a tooth.In some cases,a vein in a lobe or a lobule dichotomizes and one of the daughter veins enters the lobe or lobule,but the other enters the neighbouring lobe or lobule.This kind of dichotome is named lobes-overstepped vein. One or two of the daughter veins can be blind veins with different lengths. The daughter veins overstepping the other lobe or lobule can form an anastomosis. The existence of the lobes-overstepped vein and the anastomosis formed by the overstepped daughter vein indicate that the venation of this monotypic genus is more complex than it was considered. Sometimes the two neighbouring veins of two lobes or lobules can be extremely approached and this is the approximate vein.There are two types of anastomoses in the venation of this species. No intermediate forms of the fusion of the vascular bundles were observed between the two completely fused veins of the anastomoses and thetwo separate veins of the approximate veins. But the vestige of different degrees of the commissural veins was observed. Therefore,we consider the formation of anastomosis from the approximate veins impossible. There are three types of blind veins in the venation of this species. The blind veins might have formed by the reduction of the vein terminating in a tooth accompanied by the reduction of the tooth, the interruption of the commissural veins of the anastomoses and the interruption of a veinlet from the branching point of a vein dichotome. According to the present morphological studies, we conclude that the dichotomous venation of the leaf of Kingdonia uniflora is of a characteristic of reduction and that the anastomosis is the vestige of the reduction from the closed venation to the open one. The occurrence of this kind of venation in the leaf of this species and some ferns and gymnosperms is a result of convergent evolution.
  • Liu Jian-quan, Ho Ting-nong
    J Syst Evol. 1996, 34(6): 577-585.
    This paper describes embryological characters of Comastoma pulmonarium(Turcz.)Toyokuni for the first time,with an aim of discussing the systematic position of the genus Comastoma.The development of anther walls conforms to the dicotyledonous type.All tapetum cells origin from the primary parietal cells.The tapetum with uninucleate cells is of secretory type.The epidermis persists while endothecium degenerates.Cytokinesis in the microsporocyte meiosis is of simultaneous type and microspore tetrads are tetrahedral.Pollen grains are 3-celled.The ovary is bicarpellate,unilocular with eight series of ovules and typical with parietal placentation.The ovule is unitegmic,tenuinucellate and anatropous.Ihe embryo sac originates from a single-cell archesporium.The chalazal megaspore in linear tetrad is the functional one.The development of embryo sac is of the Polygonum type.Before fertilization,two polar nuclei fuse into a secondary nucleus.Three antipodal cells persist while divide into 8-12 cells,each of which is multiseriate containing more than 3 nuclei.The size of the antipodal cell is enlarged to be several times bigger than the normal cell.The haustorium formed from antipodal cells is distinct.Fertilization is porogamous.The pollen tube destroys a synergid to enter embryo sac and discharge the two sperms.One of the sperms fuses with the egg cell to form the zygote while the other with the scondary nucleus to form the primary endosperm nucleus almost simultaneously.The fertilization conforms to premitotic syngamy type.The development of the endosperm is of the Nuclear type.The early several divisions of the endosperm nuclei are simultaneous and each nucleus contains 2~3 nucleoli. The embryogeny corresponds to the Physalis I variation type the Soland type.The antipodal cells form a layer of“out endosperm”just out of the endosperm nucleus layer and degenerate after the division of the zygote.Compared with Gentiana,Gentianella and Lomatogonium,Comastoma is embryologically more closely related to Gentianella than to Gentiana and Lomatogonium.It shares more embryological similarities with Gentianella than the other two genera,but differs from Gentianella in some important characters such as ovule curvature,ovule series,placentation and the path of pollen tube.However,these diagnostic characters are usually used to circumscribe the taxon above the generic rank.Therefore,from embryological evidence,Comastoma is better bestowed as a generic rank.This genus is more primitive than Gentianella according to evolutionary trends of the embryological characters.
  • Xiong Zhi-ting, Chen Sing-chi, Hong De-yuan
    J Syst Evol. 1996, 34(6): 586-591.
    The nocturnal-flowering group of Hemerocallis was treated as including three separate species, H.lilioasphodelus,H.citrina and H.minor in the Florae Reipublicae Popularis Sinicae Vol.14(1980).However it is difficult to distinguish them from one another by a single feature,such as the flower number,length of perianth tube,diameter of tuberous roots,for they are strongly overlapping.In the present paper,numerical analysis was made of nine morphological characters and karyotype divergences which are of taxonomic significance as shown in the study of H. fulva and its two varieties (Xiong and Chen,1992),based on dry and living materials from China.In addition,geographical distribution pattern of the three taxa studied shows that they seem to be different geographical races or allopatric ecotypes in a topocline,since they inhabit a climate gradient from warm and moist to cold and drought condition.As a result,the present authors tend to consider it more reasonable to treat them as a single species,H.lilioasphodelus,with three subspecies,that is, H.lilioasphodelus ssp.lilioasphodelus,H.lilioasphodelus ssp. citrina (stat.nov) and H.lilioasphodelus ssp.minor(stat.nov.)
  • Huang Jin-ling, Liu Xian-zhang
    J Syst Evol. 1996, 34(6): 592-596.
    A species of the genus Tupistra,T.pingbianensis J.L.Huang et X.Z.Liu,is described as new,and its karyotype and pollen morphology are reported. The bimodal karyotype of this species is formulated as 2n=38=14m+10sm+8st+6t,and pollen grains are spheroidal,inaperturate,with rugulate exine sculpture.Based on its floral structure,karyotype and pollen morphology,T.pingbianensis J.L.Huang et X.Z.Liu is considered phylogenetically closely related to T.fungilliformis Wang et Liang.Whether the repense rhizome,solitary leaves of T.pingbianensis J.L.Huang et X.Z.Liu indicate a close relationship between the genus Tupistra and the genus Aspidistra needs further studies.
  • Li Jian-qiang
    J Syst Evol. 1996, 34(6): 597-609.
    A cladistic analysis of the genera in the family Fagaceae is made in the present paper.As a monophyletic group,the family Fagaceae includes 6 genera,namely,Lithocarpus,Castanopsis,Castanea,Trigonobalanus,Fagus and Quercus.The Betulaceae and Nothofagaceae were selected for outgroup comparison after a careful consideration.Twenty five informative characters had been used in this study.Three principles:outgroup comparison,fossil evidence and generally accepted view points of morphological evolution,were used for polarization of the characters. A data matrix was constructed by 7 ingroups,2 outgroups and 25 characters.The data matrix was analysed with the Maximal Same Step Method,Group Union Method and the Synthetic Method.Three cladograms were constructed and a parsimonious cladogram (Lenth=75)was used as the bases in discussing the intergeneric systematic relationships in Fagaceae. In the Fagaceae,the first differentiated group might be the extinct common ancester of the extant genera Lithocarpus,Castanopsis and Castanea.They are reasonably with the distinct characters:mixed inflorescence or androgynous and the female flowers with staminodes.Among the three genera,Lithocarpus was differentiated earlier than the others and it remains more primitive (entire leaves;smaller diameter of vesseles;scanty tylose;cupule scaly appendages;mixed inflorescence and the female flowers with well developed stamens in some species),Castanopsis is closely related to,but more primitive than Castanea. As in a clade group,the genus Trigonobalanus orginated apparently later than the ancester of Lithocar- pus,Castanopsis and Castanea.Fossil evidence suggests that this genus originated as early as in the Paleocene to Eocene.And some characters,for example,leaf with glandular peltate trichomes,chromosome number 2n=44,are only appeared in Trigonobalanus.Three species in this genus are disjunctly distributed in tropical Asia and South America,this genus is considered as both an isolated and primitive taxon in the Fagaceae,and it is also probably paraphyletic with the subfamily or tribe categories in this family. As shown in cladograms 1 and 2,the genus Fagus forms an isolated clade which consists of a relatively advanced taxon in the Fagaceae (with fiber tracheid and the reduction of the inner integument). In three cladograms,the clade of Quercus is the most advanced one,which is consistent with the current view-point about the systematic position of the genus Qucrcus and the concept of Qucrcus (s. l. ) in Fagaceae. The following conclusions may be reached by the author: (1) The six genera in the Fagaceae evolved in four parallel lines phylogenetically ,so they could be treated as four independent subfamilies,namely Castaneoideae ,Trigonobalanoideae,Fagoideae and Quercoideae ; (2) Parallel evolution is the main form in the phylogeny of the Fagaceae,some characters of the reproductive cycle, for example, fruit becoming ripe in the next year and the abortion of ovules etc. are the main factors which affect the gene flow among the genera in the Fagaceae; (3) In the Fagaceae, Lithocarpus is a primitive genus, and Trigonobalanus and Castanopsis both are also relatively primitive,but Castanea,Fagus and Quercus are relatively ad-vanced.
  • Jiang Lin, Lin Yuou-ruen
    J Syst Evol. 1996, 34(6): 610-620.
    Twenty-six species and eight varieties of Sect.Viscidipubes & Sect.Albibractea are endemic to Asia.Most species of Sect.Viscidipubes are distributed from low to high altitudes and cold areas in the Hengduan-Himalayan Mountains,with only a few species extending to E or S Asia.Sect.Albibractea is distributed mainly in the subtropics and tropics,lower altitudes and moist areas in S & SE Asia,with a few species extending to the Qinling range of China.Both sections are more advanced than the other sections.They were studied by cladistic analysis and outgroup comparison.Data matrix of 55 characters from stems,leaves,inflorescences,female flowers,bisexual flowers,achenes,pollen grains and chemical constitution was employed in separate and combined studies.Eighteen most parsimonious cladograms were generated with 358 steps,consistency index of 0.72 and retention index of 0.87. 1.Within Artemisia,Sect.Viscidipubes and Sect.Albibractea are sister groups to all the other groups. 2.We support the idea to separate Sect.Viscidipubes (incl.Ser.Viscidipubes,Ser.Erlangshanenses and Ser. Pleiocephalea) and Sect.Albibractea (incl.Ser.Albibractea,Ser.Flaccidae and Ser. Anomalae).The authors suggest that Ser.Anomalae include A.deversa and Ser.Erlangshanenses include A.zayuensis and A.yadongensis as well as Ser.Viscidipubes include A.gyitangensis and A.boreali-siamensis.As the result of the cladistic analysis,the authors tend to propose a new series, Ser.Tanguticae,incl.A.tangutica in the section. 3.We consider that SW China,especially W Sichuan,is the speciation center and the tration of the present distribution center.4.A.boreali-siamensis,only in N Thailand,is not related to the widely distributed species in Ser.Pleiocephalae,such as A.atrovirens,A.chingii and A.myriantha,but rather closely related to species,such as A.vexans,A.occidentali-sichuanensis,which are endemic to W.Sichuan and E.Xizang.
  • Rao Guang-yuan
    J Syst Evol. 1996, 34(6): 621-626.
    Six species of Sedum are taxonomically discussed and revised in the present paper. As a result,names of seven species,one subspecies and two varieties are reduced. Critical comments on and a full synonym of these taxa are presented. The taxonomic status of S.phyllanthum Lé Vant,and S.subtile Miq.,which were treated as doubtful species in Flora Reipulicae Popularis Sinicae (FRPS) Vol.34(1),is discussed.S.formosanum N. E. Br.,treated as a synonym of S. alfredii Hance in FRPS, is recognized as a distinct species,and it is found to extend westwards to the mainland of China. S. hakonense Makino is recorded as new to China.
  • Zhang Zhi-yun, Li Heng
    J Syst Evol. 1996, 34(6): 627-630.
    The present paper reports the habit,habitat and the morphological characters of inflorescences and flowers of Corylopsis trabeculosa (Hamamelidaceae),a species endemic tothe Dulongjiang Region,Gongshan County, Yunnan Province,China. The morphological comparison supports the opinion that it is an independent species.
  • Chen Yi-ling
    J Syst Evol. 1996, 34(6): 631-634.
  • Lang Kai-yong
    J Syst Evol. 1996, 34(6): 635-640.
  • Tan Zhong-ming, Chen Guang-hou
    J Syst Evol. 1996, 34(6): 650-652.
  • Wei Yin-xin
    J Syst Evol. 1996, 34(6): 653-671.
    A total of 48 algae samples were collected from southern bays of the Donghu Lake from September in 1963 to December in 1964.The desmids were very plentiful,164 species,75 varieties and 13 forms belonging to 20 genera were identified.Among these,two species,seven varieties and two forms are new to science**,and 12 species,25 varieties and five forms are recorded for the first time in China.The dominant species with frequent occurrence were 11 species and one variety in four seasons. The result of counting and analysing the samples collected in different seasons (six times for each) shows that the number of the taxa of Desmids in summer (June and August)was the highest,that in autumn and winter (September,October and December) the next,and that in spring (April) is the lowest.Fourty five of 252 desmids taxa are tropical and subtropical,among which 19 are either endemic to or common in S and SE Asia. The desmid flora of Wuhan district is therefore subtropical in nature and closely related to the S and