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Some lycophytes are homosporous while others are heterosporous. [5] When broadly circumscribed, the lycophytes represent a line of evolution distinct from that leading to all other vascular plants, the euphyllophytes, such as ferns, gymnosperms and flowering plants.
Historically both lycophytes and monilophytes were grouped together as pteridophytes (ferns and fern allies) on the basis of being spore-bearing ("seed-free"). In Smith's molecular phylogenetic study the ferns are characterised by lateral root origin in the endodermis , usually mesarch protoxylem in shoots, a pseudoendospore, plasmodial tapetum ...
Lycopodiopsida is a class of vascular plants also known as lycopsids, [1] lycopods, or lycophytes. Members of the class are also called clubmosses , firmosses , spikemosses and quillworts . They have dichotomously branching stems bearing simple leaves called microphylls and reproduce by means of spores borne in sporangia on the sides of the ...
The Pteridophyte Phylogeny Group (PPG) is an informal international group of systematic botanists who collaborate to establish on the classification of pteridophytes (lycophytes and ferns) that reflects knowledge about plant relationships discovered through phylogenetic studies. In 2016, the group published a classification for extant ...
The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers.They differ from mosses by being vascular, i.e., having specialized tissues that conduct water and nutrients, and in having life cycles in which the branched sporophyte is the dominant phase.
However, genetic analysis has shown Psilotum to be a reduced fern. [6] It is not clear whether leaf gaps are a homologous trait of megaphyllous organisms or have evolved more than once. [1] While the simple definitions (microphylls: one vein, macrophylls: more than one) can still be used in modern botany, the evolutionary history is harder to ...
Fern allies and ferns were sometimes grouped together as division Pteridophyta. [1] Another traditional classification scheme of living plants is as follows (here, the first three classes are the "fern allies"): Kingdom: Plantae. Division Tracheophyta (vascular plants) Class Lycopodiopsida, clubmosses and related plants (fern-allies)
Polypodiales are unique in bearing sporangia with a vertical annulus interrupted by the stalk and stomium. [2] These sporangial characters were used by Johann Jakob Bernhardi to define a group of ferns he called the "Cathetogyratae"; [3] the Pteridophyte Phylogeny Group has suggested reviving this name as the informal term cathetogyrates, to replace the ambiguously circumscribed term "polypods ...