摘要:

Abstract—Separate cladistic analyses of the green algae, liverworts, and hornworts are presented. Classificatory and evolutionary implications of these analyses, in addition to our previously published cladistic analyses of mosses and the embryophytes as a whole, are discussed. The embryophytes are monophyletic, and are part of a larger monophyletic group that includes some of the green algae (the “charophytes”). Important evolutionary transformations in the early phylogeny of the land plants include: (1) retention of the zygote on the haploid plant (gametophyte), with the sporophyte generation arisingde novoby delaying meiosis, (2) independent elaboration of an elongate sporophyte in some liverworts, some hornworts, and in the moss‐tracheophyte clade, (3) independent origin of radial (axial) symmetry in the gametophyte in some liverworts and in the moss‐tracheophyte clade, (4) independent origin of leaves on the gametophyte in some liverworts and in mosses, and (5) the unique development of a branching sporophyte with multiple sporangia in the trac

ISSN:0748-3007    

DOI:10.1111/j.1096-0031.1985.tb00431.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Abstract—The phylogenetic relationships of nineteen extant and fossil seed plants are considered. Analysis of 31 characters produced ten topologically similar and equally parsimonious cladograms. A strict consensus tree derived from these cladograms placesLyginopterisas the sister taxon to the other seed plants included. Within this clade all the taxa considered, except medullosans and cycads, form a single monophyletic group defined by the presence of flattened seeds and saccate pollen (“platy‐sperms”). Relationships between medullosans, cycads, and “platysperms” were not resolved, but within the “platysperm” clade conifers and cordaites (Cordaixylon, Mesoxylon) +Ginkgoform a monophyletic group (“coniferophytes”). The “higher platysperms” (glossopterids,Caytonia, corystosperms, Bennettitales,Pentoxylon, Gnetales, and angiosperms) are also monophyletic, but their relationship to “coniferophytes,” peltasperms, andCallistophytonis unresolved.Pentoxylonis placed as sister taxon to the Bennettitales, and together they form the sister group to a clade in which Gnetales and angiosperm are sister taxa. The Bennettitales +Pentoxylon+ Gnetales + angiosperms (“anthophytes”) form a monophyletic sister group to the corystosperms. This analysis is compared with current classifications of seed plants. It does not support a close relationship between Bennettitales and cycads, it provides no evidence for seed plant polyphyly, and it strongly suggests that the current concept of seed ferns has little

ISSN:0748-3007    

DOI:10.1111/j.1096-0031.1985.tb00432.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Abstract—Our knowledge of fundamental angiosperm interrelationships is still very incomplete. The absence of a narrowly circumscribed gymnosperm outgroup, ideally the sister group, makes character evaluation, necessary for a cladistic analysis, difficult. According to current views the superorder Magnoliiflorae with a number of other groups, for example the monocotyledons, may represent a complex of families near the base of the angiosperms. Interrelationships of groups within the monocotyledons are much better understood than those between groups within the dicotyledons. A cladogram of monocotyledon orders based on earlier work by R. Dahlgren, H. T. Clifford, and F. N. Rasmussen is presented. A data matrix for a sample of the angiosperms with 61 characters for 49 taxa, mostly magnoliifloran and related families, is presented. The characters are polarized mainly according to the current view that the primitive angiosperm morphotype is a woody dicotyledon with strobiloid flowers. As an alternative the matrix is adjusted following W. C. Burger's conjecture that the primitive angiosperm was a herbaceous monocotyledon with trimerous flowers. Both matrices were run in a computerized parsimony analysis, resulting in numerous equally parsimonious solutions. This result is illustrative of the great homoplasy in the available character information, and also of how little actually is known about fundamental angiosperm interrelationships or phylogen

ISSN:0748-3007    

DOI:10.1111/j.1096-0031.1985.tb00433.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Abstract—A cladogram of green plants involving all major extant groups of green algae, bryophytes, pteridophytes, and seed plants is presented. It is partly based on contributions by B. Mishler and S. Churchill, H. Wagner, and P. Crane. The relationships of green plants to other green organisms (Prochloron, euglenophytes) are discussed. The characters and subclades of the cladogram are briefly discussed, with an attempt to indicate weak points. The possibility of including some major extinct groups is considered. A cladistic classification consistent with the cladogram is presented. Grades are abandoned as taxa and major clades like the division Chlorophyta (green algae excluding micro‐monadophytes and charophytessensuMattox and Stewart), the division Streptophyta (charophytes + embryophytes), the subdivision Embryophytina (land plants or embryophytes), the superclass Tracheidatae (tracheophytes), and the class Spermatopsida (seed plants) are recogni

ISSN:0748-3007    

DOI:10.1111/j.1096-0031.1985.tb00434.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

ISSN:0748-3007    

DOI:10.1111/j.1096-0031.1985.tb00435.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Book reviewed in this article:Milkweed Butterflies: Their Cladistics and Biology.— P. R. Ackery and R. I. Vane‐Wright. 1984.Scala Millettiearum: A Survey of the Genera of the Tribe Millettieae (Legum.‐Pap.) with Methodological Considerations.— R. Geesink. 1984.Mechanisms of Morphological Evolution.— W. Art

ISSN:0748-3007    

DOI:10.1111/j.1096-0031.1985.tb00436.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

ISSN:0748-3007    

DOI:10.1111/j.1096-0031.1985.tb00437.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY