Table of Contents

18 January 2005, Volume 43 Issue 1
    Research Articles
  • 1LI Hong-Fang, 2REN Yi*
    J Syst Evol. 2005, 43(1): 1-11.
    The systematic position of the Eupteleaceae, a monogeneric family including only two species (Euptelea polyandra and E. pleiosperma) and endemic to East Asia, has long been in dispute. This paper deals with the variation of the vessel perforation plates of the secondary xylem of the stem of E. pleiosperma in order to provide new anatomical evidence for a better understanding of the systematic position of this family. The results showed that there were two types of vessels in the secondary xylem of the stem of the species, the tracheid-like vessels and typical vessels. In the tracheid-like vessels, the perforation pits were larger than those in the lateral wall, arranged irregularly and did not exhibit typical morphological features of perforation plates, and the membrane of the perforation pits disappeared completely or partly. In the typical vessels, the perforation plates were of varying forms, falling into several subtypes: reticulate perforation plates (including the foraminate ones); reticulate-scalariform perforation plates in which the perforation pits were both reticulate and scalariform; scalariform perforation plates in which scalariform multi-perforation plates were often observed; the transitional form from scalariform perforation plates to simple perforation ones; and some other forms of perforation plates which could not be referred to any subtypes mentioned above. The membrane remnants could be observed only in the perforation pits of the scalariform perforation plates. Multiple end wall and lateral-wall perforation plates were also observed in the secondary xylem. Based on the present results and a comparison between the perforation plate types in the Eupteleaceae with those of the other members of Ranunculales, we considered that the Eupteleaceae might occupy a basal position in the order. We also inferred that the formation of the perforation plates in E. pleiosperma may have undergone different pathways.
  • GAO Tian-Gang, CHEN Yi-Lin
    J Syst Evol. 2005, 43(1): 12-21.
    The systematic position of the taxonomically controversial Nannoglottis is investigated based on SEM observation on microcharacters of the ligules in eight species of the genus. All the species are characterized by having an adaxial epidermis of the ligules consisting of oblong, tabular cells, with the radical and tangential walls being straight; the outer wall with a characteristic thickening along the median plane of the cell; the median plane of the cuticle of outer wall with a pattern of longitudinal rugose stripes; and no systematic connection between the patterns of adjacent cells. This supports a close affinity between the genus Nannoglottis and Astereae, and also indicates the unique systematic position of this genus in the tribe. These results agree with those of the study of the phylogeny of Astereae using ITS sequences. The evolutionary trends of some microcharacters and the utility of microcharacters in the taxonomy of some species of Nannoglottis are also discussed.
  • LIU Yan-Ling, XU Li-Ming, NI Xue-Ming*, ZHAO Jia-Rong
    J Syst Evol. 2005, 43(1): 22-30.
    The Nymphaeaceae are one of the most important taxa for understanding the origin and evolution of primitive angiosperms due to its basal position in the cladograms of the angiosperms recently given based both on several gene sequences and on morphological characters, but phylogenetic relationships within the family have not as yet been resolved. The sequences of nrDNA ITS region of 11 species representing seven genera of the Nymphaeaceae and one outgroup, Ceratophyllum demersum, were used to reconstruct the phylogeny of the family using PAUP4.0b4A. Three most parsimonious trees (Length=1125, CI=0.7618 and RI=0.7214) were obtained. In the consensus tree: (1) Nelumbo was basal to the other genera with a bootstrap value of 100% and occupied an isolated position, so it could be separated from the Nymphaeaceae and placed in its own family, Nelumbonaceae, and its own order, Nelumbonales; (2) Nuphar was monophyletic, nested in the basal position of clade II and was strongly supported to be the sister group of the other genera (excluding Nelumbo) of the Nymphaeaceae, suggesting that its traditional inclusion in the Nymphaeaceae should be maintained; (3) Cabomba and Brasenia were sister group and formed a subclade with a bootstrap value of 99%, indicating their close affinity; (4) Nymphaea was strongly supported to be the sister group of a subclade comprising Euryale and Victoria with a bootstrap value of 94%, indicating that they should be placed in the Nymphaeaceae.
  • 1LI Wei-Ping, 2LIU Sheng-Xiang
    J Syst Evol. 2005, 43(1): 31-36.
    Collections of Aster ageratoides var. gerlachii (Hance) Chang from Shennongjia, Hubei Province, central China, have long been erroneously referred to A. ageratoides var. micranthus Ling. A comparative study on the morphology and cytology of the two varieties was conducted to gain a better understanding of their relationships. The possible factors causing the misidentification are discussed and the diagnostic characters between the two varieties are redefined. The absence of horizontal rhizome in var. micranthus was found to be of important taxonomic value. A. ageratoides var. micranthus was a diploid with the karyotype formula of 2n=2x=18=18m, with the karyotype belonging to 1A type in karyotypic asymmetry, whereas A. ageratoides var. gerlachii was a tetraploid with the karyotype formula of 2n=4x=36=32m+4sm (2SAT), with the karyotype belonging to 2A type. A. ageratoides var. gerlachii is a newly recorded taxon in Hubei.
  • 1 2WANG Ying-Qiang, 1ZHANG Dian-Xiang*, 1CHEN Zhong-Yi
    J Syst Evol. 2005, 43(1): 37-49.
    Comparative studies on pollination biology of two floral morphs in Alpinia hainanensis were carried out in Hainan Province and Guangzhou, Guangdong Province, southern China. Populations of A. hainanensis have two floral morphs and the behaviors of stylar movements in the two floral morphs are similar to those found in other species of Alpinia previously reported. However, the stylar movement behavior of the cataflexistylous morph is 2 h slower than that of the anaflexistylous morph. There are some asynchronous stylar movements on the same floral morph, even on the same inflorescence. Yet, all anthers of the anaflexistylous floral morphs dehisce only after all stigmas of the same phenotype have moved out of the receptive position, viz., above the anthers. Our results indicate that the anaflexistylous morph has more pollen grains per flower, higher pollen/ovule ratio (P/O), and larger nectar volume than the cataflexistylous morph, while approximately equal ovule numbers, sugar and amino acid concentration. Field experiments indicate that the fruit sets are significantly high in both artificially out-crossed and self-pollinated flowers, while no fruit set was observed in bagged emasculated flowers and the unpollinated bagged flowers. These facts exhibit that A. hainanensis is self-compatible and there is no self-pollination and agamospermy in the species. There are significant differences in the fruit sets among the anaflexistylous flowers with hand-pollination treatments at different times during the day, but not in the cataflexistylous flowers. The fruit set by hand pollination is much higher than that under natural condition. This means that A. hainanensis is dependent upon insects for pollination, and insufficiency of pollinators limited fruit set under natural condition. The effective pollinators were Ameglla sp. and two species of carpenter bees (Xylocopa sp.). However, only fewer insects at a lower frequency visited flowers of A. hainanensis in nature. The breeding system of A. hainanensis is xenogamy with flexistyly.
  • 1LI Zhen-Ji, 2Benito C. TAN *
    J Syst Evol. 2005, 43(1): 50-59.
    Examination of some 80 historical herbarium specimens preserved in a number of institutions in Fujian Province and our recent collections made from Mt. Wuyi Shan area shows that there are 18 species and one variety of Selaginella in the province, of which, Selaginella albociliata, S. braunii and S. ciliaris are three new records for the provincial flora. A new key to the species of this genus in the province is given. Pertinent taxonomic notes and phytogeographical discussion of the species diversity of Fujian Selaginella are also provided.
  • CAI Lian-Bing
    J Syst Evol. 2005, 43(1): 60-67.
    Based on both herbarium and field observations, Ptilagrostis dichotoma Keng ex Tzvel. and P. junatovii Grub. are reduced to synonymy of P. mongholica (Turcz. ex Trin.) Griseb. and of P. concinna (Hook. f.) Roshev. Respectively, and a new combination, P. roshevitsiana (Tzvel.) L. B. Cai, is proposed.
  • YANG Chang-You
    J Syst Evol. 2005, 43(1): 68-70.
    A new species of the genus Delphinium (Ranunculaceae) from Tianshan, Xinjiang, China, D. neowentsaii C. Y. Yang, is described and illustrated. The new species is similar to D. laxiflorum DC. in having leaves reniform, petioles not dilated at base, flowers small, inflorescence laxly racemose, pedicels adpressed pubescent, spur of the upper sepal conic-subulate, 13-15 mm long, 3 mm wide at base, outside pubescent, sepals blue, but differs by having both petals and staminodes yellowish.
  • 1GOU Guang-Qian, 2WANG Pei-Shan
    J Syst Evol. 2005, 43(1): 71-72.
    Selaginella xishuiensis G. Q. Gou & P. S. Wang, a new species of the Selaginellaceae from Guizhou, China, is described and illustrated. The new species is related to S. davidii Franch. in habit and size, but differs by having leaves ciliate along margin. It is also similar to S. prostrata H. S. Kung in habit, but differs by having sporophylls homomorphic.
  • 1SHEN Ze-Hao, 2ZHAO Zi-En
    J Syst Evol. 2005, 43(1): 73-75.
    Arenaria shennongjiaensis Z. E. Zhao & Z. H. Shen, a new species of the Caryophyllaceae from Shennongjia, Hubei, China, is described and illustrated. It is related to A. giraldii (Diels) Mattf. in having fusiform root, and petals tooth-like lobed, but differs by having stem with one line of glandular hairs, and petals tooth-like 4-lobed, with the lobes being 2-lobulate.
  • YAN Shuang-Xi, WANG Peng-Fei, ZHU Chang-Shan, YANG Qiu-Sheng*, KONG De-Zheng
    J Syst Evol. 2005, 43(1): 76-78.
    Clematis acerifolia var. elobata S. X. Yan, a new variety of the Ranunculaceae from Henan, China, is described. The variety is different from the typical one in being dwarf, less than 20 cm high, leaves ovate or broadly ovate, not lobed, base broadly cuneate or subtruncate, margin irregularly serrate.
  • LIN Qi, CHEN Chia-Jui
    J Syst Evol. 2005, 43(1): 79-81.
    Based on a study of the type material of Elatostema gagnepainianum H. Schröter, a lectotype was designated for this name and it was treated as a new synonym of Procris crenata C. B. Robinson.
  • 1YEN Chi*, 1YANG Jun-Liang, 2YEN Yang
    J Syst Evol. 2005, 43(1): 82-93.
    Taxonomy is a tool for organism recognition, an understanding of phylogenetic relationships among organisms, a guide for germplasm utilization, and a common language for communication. Therefore, a taxonomic treatment needs to reflect our current understanding of such relationships. In nature, there are only two absolute units of living organisms: individuals and species. A species is a group of individuals who are connected to each other as a unit by their indispensable relationships of breeding. Reproductive separation is an essential boundary between species, and the only factor to form independent gene pools during organismal evolution. Since there is no absolute boundary among taxa above species, any taxonomic treatments above species cannot avoid arbitrariness. Nevertheless, some classification should be made for the convenience of their description, utility and/or study. This paper classifies the biosystematic relationships among taxa in Triticeae on the basis of genetic studies. The principles for our taxonomic treatment are: (1) reflecting the current understanding of the phylogeny among the species involved, (2) being convenient for germplasm utilization, and (3) avoiding unnecessary radical change apart from the tradition.