Pteridophytes are free-sporing vascular land plants that evolutionarily link bryophytes and seed plants. Conventional, group (taxon)-based hierarchic classifications of pteridophytes using phenetic characters are briefly reviewed. Review is also made for recent tree-based cladistic analyses and molecular phylogenetic analyses with increasingly large data sets of multiple genes (compared to single genes in previous studies) and increasingly large numbers of species representing major groups of pteridophytes (compared to particular groups in previous studies), and it is extended to most recent analyses of estimating divergence times of pteridophytes. These classifications, phylogenetics, and divergence time estimates have improved our understanding of the diversity and historical structure of pteridophytes. Heterospory is noted with reference to its origins, endospory, fertilization, and dispersal. Finally, monophyletic and paraphyletic groups recently proposed or re-recognized are briefly described.
A new species of the genus Thismia (Burmanniaceae), T. mullerensis, is described and illustrated from Muller Range, Central Kalimantan, Indonesia. It appears to belong to sect. Euthismia Schltr. (sect. Thismia) in having inner perianth free, spreading and roots vermiform, creeping, and to subsect. Odoardoa Schltr., having perianth lobes equal in length and size. It most resembles T. alba that was collected in 1930 from Malay Peninsula and T. lauriana reported from Central Kalimantan in 1996, but differs in flower structure and color. This species is the third species of the genus Thismia reported from Central Kalimantan.
Musa beccarii Simmonds var. beccarii is re-described based on extensive field studies in the eastern part of Sabah, Malaysia. Then a new variety of wild banana, M. beccarii Simmonds var. hottana Hakkinen, is described and illustrated. This extremely rare new variety was only found in one area at the lower Kinanbatangan River, eastern part of Sabah. It is also considered that M. pigmaea M. Hotta nom. nud. from East Kalimantan, Indonesia, might be the synonym or a closely related variety to the new variety.
Molecular phylogenetic analyses were performed using data sets derived from DNA sequences of the plastid genome (matK and trnK introns) and the nuclear genome (rDNA ITS) in an examination of relationships of all sections of Phalaenopsis and closely related genera. The following insights were provided: (1) The genera Lesliea and Nothodoritis are nested within Phalaenopsis. (2) Phalaenopsis subgenus Aphyllae and section Esmeralda, often treated as the independent genera Kingidium and Doritis respectively, are also nested within Phalaenopsis. (3) Two subgenera of Phalaenopsis, namely, Phalaenopsis and Parishianae, are not monophyletic. (4) Phalaenopsis sections Deliciosae, Stauroglottis, Amboinenses and Zebrinae are not monophyletic. (5) Inconsistencies between the plastid and nuclear lineages indicate a hybrid origin of Phalaenopsis minus and Phalaenopsis philippinensis. (6) In light of these findings, and to accommodate phylogenetic integrity and stability in nomenclature, we adopt a broadly defined Doritis characterized by the possession of four pollinia, an explicit character state.
New combinations for two taxa, Arabidopsis kamchatica (Fisch. ex DC.) K. Shimizu & Kudoh and A. kamchatica subsp. kawasakiana (Makino) K. Shimizu & Kudoh, are proposed. The lectotypes of both names were chosen. The former taxon was previously recognized as either Arabis kamchatica, Cardaminopsis kamchatica or an infraspecific taxon under Arabis lyrata or Arabidopsis lyrata. The latter was previously recognized as either Arabis kawasakiana, Arabis lyrata subsp. kawasakiana or a synonym of Arabidopsis lyrata subsp. kamchatica. We here report the bivalent nature of meiotic chromosome of A. kamchatica subsp. kawasakiana, n=16_<II> and 2n=32. We also provide a molecular evidence of allotetraploidy using a nuclear Chalcone Synthase (CHS) sequence. In conjunction with former chromosomal and morphological studies, we considered that both taxa should be placed under the genus Arabidopsis but distinct from Arabidopsis lyrata. Arabidopsis kamchatica will provide a unique opportunity for the molecular genetic analysis of genome duplication, by utilizing the genetic and genomic information on a model species Arabidopsis thaliana.
Three infraspecific taxa, var. japonica, var. hirsutiflora, and var. boniensis, were recognized in Angelica japonica by Yamazaki (1990). He considered that var. boninensis is distributed both in the Bonin and the Daito Islands. In this paper, in order to evaluate taxonomic status of var. boninensis, we examined the populations of the three varieties on the basis of allozyme analysis. In the obtained UPGMA dendrogram, three major clusters of the populations from the following three areas were recognized: I) the southern part of Kyushu, the Hedo population of Okinawa Island and the Daito Islands; II) the Bonin Islands; and III) Okinawa Island and the Yaeyama Islands. The plant populations of the Daito and the Bonin Islands, which were identified as var. boninensis by Yamazaki (1990), were divided into two different clusters based on the UPGMA dendrogram. The values of genetic identities among the three clusters were lower than the mean values of those among conspecific plant populations. Differences in leaflet shape coincided with these clusters. We concluded that the clusters I, II, and III can be taxonomically treated as independent species Angelica japonica A. Gray, A. boninensis Tuyama, and A. hirsutiflora Liu, Chao et Chung, respectively.
ITS and ETS If sequence data were used to estimate the phylogeny of 13 Japanese Schoenoplectus species, and karyomorphological observations were made on 14 species of this genus. Two major clades were identified in the Japanese Schoenoplectus molecular phylogenetic tree: (1) one including all species of section Actaeogeton, and (2) the another comprising the two sections Malacogeton and Schoenoplectus. Phylogenetic analysis, including three published species of section Schoenoplectus, supported a monophyly of the two major clades. These molecular phylogenetic data also support the intrageneric relationships and morphological characters of genus Schoenoplectus, as defined by Smith & Hayasaka (2001). The section Actaeogeton clade and the sections Malacogeton and Schoenoplectus clade showed the same chromosomal evolution; each clade had both high and low chromosome numbers. The high chromosome numbers may arise by polyploidy because chromosome sizes were almost equal in both. Therefore, chromosomal evolution in the genus Schoenoplectus may be caused more by polyploidy more than aneuploidy. In our study, the putative natural hybrids, S. × trapezoideus and S. × uzenensis were found. The chromosome number of S. × trapezoideus was 2n=43 and S. × uzenensis was 2n=58. These two hybrids had an intermediate chromosome number of both putative parents.
The floral scent of Chimonanthus praecox (L.) Link (Calycanthaceae; Magnoliids) was collected by the headspace method and analyzed using gas chromatography - mass spectrometry (GC-MS). The main components of the floral scents are benzyl acetate (42.2 %), frans-β-ocimene (24.8%), linalool (17.2 %), and benzyl alcohol (6.9%). These compounds are common in the scent profiles of many plants throughout the angiosperms. In addition, the female and male stages (phases) of the protogynous, drooping flowers of C. praecox f. concolor Makino were observed. In the female phase the stamens are bent toward the tepals away from the pistils at a right angle. After approximately two days the stamens commence to move to enclose the pistils. It takes from one to four days for the stamens to eventually enclose the pistils in the various flowers and then anthers shed their pollen.
The chromosome numbers of two species of Cayratia (Vitaceae) are reported. Cayratia japonica var. mollis had a diploid number of 2n=40, while C. trifolia was found to have both diploids of 2n=40 and tetraploids of 2n=80.