摘要:

Anatomy of leaf, stem, and root of more than 100 species in subtribe Dendrobiinae (Orchidaceae) was studied with the light microscope to provide a comparative anatomical treatment of these organs, to serve as an independent source of evidence that might be taxonomically important, and to recommend such reinterpretations of existing classifications as are suggested by a phylogenetic assessment of data. We based our classification on that of Rudolf Schlechter as the most complete and widely accepted today. We found that the anatomy of plants in subtribe Dendrobiinae reflects a high degree of morphological diversity, and many of the anatomical characters appear to be homoplasous. When these anatomical data are used to interpret the systematic relationships among the genera, they indicate thatDendrobiumis not monophyletic and thatCadetiaandPseuderiaare apparently nested within the structure ofDendrobiumwhen sectionGrastidiumis chosen as a functional outgroup. Lack of resolution in the strict consensus tree illustrates the difficulty of determining the phylogenetic relationships of many of Schlechter's sections using anatomical characters. Nevertheless, we recommend that his sectional classification, with appropriate modifications based on available data, be retained for the present, pending a more detailed understanding of the phylogeny of Dendrobiinae based on morphology, micromorphology, anatomy, and DNA studies.

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1996.tb00483.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

In a study based on morphological, embryological and chemical data of the Plantaginaceae, within the subclass Sympetalae or Asteridae, the superorder Lamianae is shown to be monophyletic. However, it was not possible to reconstruct the phylogeny within Lamianae or to find a sister‐group for the monophyletic Plantaginaceae – Hydrostachyaceae for the latter is rejected. Three or rarely four genera have previously been recognized within Plantaginaceae, but in both casesPlantagoappears as polyphyletic, which is considered unacceptable. Six clades are recognized as subgenera withinPlantago:subgen.Plantago(c. 131 species), subgen.Coronopus(c. 11 species), subgen.Littorella(three species), subgen.Psyllium(c. 16 species), subgen.Bougueria(one species), and subgen.Albicans(51 species). WithinP. subgen.Plantago, the paraphyletic sect.Plantago(c. 42 species) is found in all parts of the world except South America, New Zealand, Australia, and New Guinea, where sect.Oliganthosand sect.Mesembryniaevicariate. It is not possible to infer the phylogeny within sect.Plantago, for example between the endemic species from distant Pacific Islands; their common ancestor might be a species that once had a very wide distribution. Keys to genera, subgenera, sections and series are given. Only one genus,PlantagoL., is recognized. The following proposals are made in the Appendix:P. ser.OliganthosRahn, ser. nov.;P. ser.Carpophorae(Rahn) Rahn, stat. nov. (= sect.C.);P. ser.Microcalyx(Pilg.) Rahn, stat. nov. (= sect.M.);P. unibrackteataRahn, nom. nov. (=P. unifloraHook.f. non L.);P. subgen.Littorella(P. J. Bergius) Rahn, stat. nov. (=LittorellaP. J. Bergius);P. araucanaRahn, nom. nov. (=Littorella australisGriseb. nonPlantago australisLam.);P. americana(Fernald) Rahn, comb. nov.(=Littorellaa.);P. subgen.Bougueria(Decne.) Rahn, stat. nov. (=BougueriaDecne.);P. nubicola(Decne.) Rahn, comb. nov. (=Bougueria n. Decne.);P. subgen.AlbicansRahn, subgen. nov. Ten lectotypes are selec

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1996.tb00484.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY