monilophytes

• clade containing monilophytes, gymnosperms and anthrophyta • Multiple vascular strands in each leaf (lycophytes are microphylls) • Functional ecological difference is not great but shows different evolutionary origins • Probably evolved from leafless ancestors (ancestor of euphylls and lycopods) • Two separate origins of euphylls in euphyllophytes

• 405-375 mya • Larger plants that rhyniophytes with more complex dichotomous branching • No leaves, but enations in some species; rhizomes but not roots • Clusters of sporangia at tips of fertile branches

• Circinate leaf development (curled young leaf) • Leaves: Peritole is the stem and lamina is the blade of the leaf and rachis is the centre of the lamina • Lamina can be pinnate form or bipinnate form • Ground level rhizomes but also have true roots

• Cluster of sporangia on underside or margins of leaves • Clustered in sorus (sori) • Leptosporangium means that the sporangia are on a short stalk • Spores are surrounded with an annulus (thickened cell walls on three sides) • When spores develop, the annulus dries out and shrinks causing it to contract and rip open the spore sac and the spores are thrown out

• Spores land on the ground and grow a haploid gametophyte with two thaloid lobes (small but photosynthetic) • Gametangia are formed (antheridia and archegonia) • Sperm are not dispersed at the same time that the eggs are receptive • Larger gametophytes (just produce eggs) send out signals to smaller gametophytes telling them just to produce sperm (they can be bisexual but often are not)

• Marsileaceae (rooted water ferns) • Salviniaceae (floating water ferns) • Independent evolution of heterospory in these groups

• Tropical and subtropical, often in montane forests • Leaves large and 1- to 3- pinnate • Commonly with large fleshy rhizome • Gametophytes flat, surface-dwelling, photosynthetic, up to 2cm long • Eggs and sperm are produced and fuse, growing a sporophyte

• Leaves divided into basal vegetative part and sporangium-bearing upper segment (may have derived from dichotomous branching) • Homosporous • Subterranean gametophyte with symbiotic fungus

• Simplified seeming primitive traits like rhinophyltes • Dichotomous branching; lacks leaves but has enations • Simple vascular strand in stem (protostele) • Lacks roots but has rhizomes with rhizoids and endomycorrhizae fungus • Non-photosynthetic gametophyte with symbiotic fungus

• Usually in locally damp sites such as river banks • Whorled branches and scale-like leaves at nodes • Distinctive stem anatomy: hollow, ribbed stem with siliceous deposits • Distinctive strobilus with sporangia set on short stalks (sporangiophores) • Green, free-living gametophytes (1-3cm)