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A pteridophyte is a vascular plant (with xylem and phloem) that reproduces by means of spores. Because pteridophytes produce neither flowers nor seeds , they are sometimes referred to as " cryptogams ", meaning that their means of reproduction is hidden.
A prothallus, or prothallium, (from Latin pro = forwards and Greek θαλλος (thallos) = twig) is usually the gametophyte stage in the life of a fern or other pteridophyte. Occasionally the term is also used to describe the young gametophyte of a liverwort or peat moss as well. In lichens it refers to the region of the thallus that is free ...
Polystichum setiferum, a fern Grimmia pulvinata, a moss Pelvetia canaliculata, a brown alga Hypholoma fasciculare, a fungus. A cryptogam (scientific name Cryptogamae) is a plant, in the broad sense of the word, or a plant-like organism that share similar characteristics, such as being multicellular, photosynthetic, and primarily immobile, that reproduces via spores rather than through flowers ...
Lycopods reproduce asexually by spores. The plants have an underground sexual phase that produces gametes , and this alternates in the lifecycle with the spore-producing plant. The prothallium developed from the spore is a subterranean mass of tissue of considerable size, and bears both the male and female organs ( antheridia and archegonia ...
In seed plants (gymnosperms and flowering plants), the sporophyte forms most of the visible plant, and the gametophyte is very small. Flowering plants reproduce sexually using flowers, which contain male and female parts: these may be within the same (hermaphrodite) flower, on different flowers on the same plant, or on different plants.
A proposed phylogeny of the vascular plants after Kenrick and Crane 1997 [15] is as follows, with modification to the gymnosperms from Christenhusz et al. (2011a), [16] Pteridophyta from Smith et al. [17] and lycophytes and ferns by Christenhusz et al. (2011b) [18] The cladogram distinguishes the rhyniophytes from the "true" tracheophytes, the ...
Lycopodioideae is a subfamily in the family Lycopodiaceae in the Pteridophyte Phylogeny Group classification of 2016 (PPG I). [1] It is equivalent to a broad circumscription of the genus Lycopodium in other classifications. Like all lycophytes, members of the Lycopodioideae reproduce by spores.
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.