1!Club Mosses, Ferns & Horsetails:!the Seed-free Vascular Plants!Vascular Plants - a quick review!Two unrelated groups within “cryptogams” – seed free vascular plants – are recognized as phyla:!1. Lycopodiophyta : lycopods !2. Polypodiophyta: ferns, horsetails, and whisk ferns !Vascular Plants - a quick review!They produce free spores, the principal dispersal units, via meiosis. Spore: a reproductive cell, capable of developing into an adult without fusion with another cell. !spores!Why were the seed-free plants “grouped” together?!spores!Vascular Plants - a quick review!Spores develop within a sporangium (pl. sporangia)!sporangium!Why were the seed-free plants “grouped” together?!2!spores!Vascular Plants - a quick review!Spores germinate and develop into gametophytes that exist independently of the spore-producing plants. The gametophytes (haploid, n) tend to be inconspicuous and short-lived.!gametophyte!sporangium!Why were the seed-free plants “grouped” together?!spores!Vascular Plants - a quick review!Like all plants, seed-free plants produce two kinds of gametes in their gametophytes: sperm and egg that unite to form a zygote (2n or diploid) via fertilization!gametophyte!sporangium!zygote!Why were the seed-free plants “grouped” together?!spores!Vascular Plants - a quick review!The sporophyte (2n) develops from the zygote and is more conspicuous, usually perennial and lives for an indefinite period!gametophyte!sporangium!zygote!sporophyte!Why were the seed-free plants “grouped” together?!Wisconsin Seed-free Plants!The best website to identify and see images of Wisconsinʼs seed-free plants is Gary Fewlessʼ at UW-Green Bay; links provided below!Key to Ferns and Fern Allies of Wisconsin List of Pteridophytes of Wisconsin Glossary of Fern Terminology also: Michigan Online Flora3!The best manual to identify lycopods and ferns is Ferns of Northeastern and Central North America (2nd ed.) in the Peterson Field Guides!Wisconsin Seed-free Plants!Warning: !!Families and genera (and thus species names) are changing quickly in the seed-free plants!Phylum Lycopodiophyta"club mosses, spike mosses, quillworts!Leaves microphylls: generally small, simple, one-veined leaves. Microphylls evolved by the process of enation and vascularization. An enation is a veinless, lateral protrubence on the stem. When the enation becomes vascularized it is termed a microphyll.!Sporangia: the spore producers on the sporophytes are located singly on the upper surfaces or in axils of the bracts of a cone or of green leaves!Phylum Lycopodiophyta!This group arose in the Later Silurian about 420 million years ago and was dominant in the Carboniferous and used to be much more diverse.!Carboniferous forest from Illinois!Phylum Lycopodiophyta!Lycopodiaceae - club mosses!Diphasiastrum complanatum!Ground cedar, crowfoot !15 genera and about 375 species!!Lycopodium now split into several genera!!cosmopolitan distribution, most diverse in tropics!Evergreen, stems elongate and dichotomously branching. Leaves often densely covering the stem. !Oily compounds in the cell walls ignite rapidly into a flash of light and were used by magicians and sorcerers in the Middle Ages. More recently they were used as a flash early in photography and in experimental photocopying machines. Many species over-collected for Christmas wreaths.!4!Phylum Lycopodiophyta!Lycopodiaceae - club mosses!Homosporous: “same spore” - one kind of spore produced; cones terete (rounded)!Phylum Lycopodiophyta!Lycopodiaceae - club mosses!other examples!Dendrolycopodium obscurum!Ground pine!Phylum Lycopodiophyta!Lycopodiaceae - club mosses!other examples!Lycopodiella inundata!Bog club moss!Phylum Lycopodiophyta!Lycopodiaceae - club mosses!other examples!Huperzia lucidula!Shiny club moss!Alkaloid for Alzheimers? !5!Phylum Lycopodiophyta!Huperzia lucidula!Shiny club moss!Polytrichum!forest mosses!Phylum Lycopodiophyta!Selaginellaceae - spike mosses!1 genus and about 750 species!!Mainly tropical family with some species extending into arctic regions of both hemispheres!Leaves spirally arranged and often 4-ranked on the secondary and ultimate branches. !!Spores borne in or near the axils of well-differentiated sprophylls, usually on 4 sided stroboli.!!!Phylum Lycopodiophyta!Selaginellaceae - spike mosses!1 genus and about 750 species!!Mainly tropical family with some species extending into arctic regions of both hemispheres!Leaves spirally arranged and often 4-ranked on the secondary and ultimate branches. !!Spores borne in or near the axils of well-differentiated sprophylls, usually on 4 sided stroboli.!!!Heterosporous: “different” spores !!Unlike Lycopodiaceae, Selaginellaceae are heterosporous with different types of spores: microspores and megaspore (not related to size) the micro give rise to male gametophytes and the mega give rise to the female gametophytes.!6!Phylum Lycopodiophyta!Selaginellaceae - spike mosses!Heterosporous: “different” spores !!Unlike Lycopodiaceae, Selaginellaceae are heterosporous with different types of spores: microspores and megaspore (not related to size) the micro give rise to male gametophytes and the mega give rise to the female gametophytes.!Phylum Lycopodiophyta!Selaginellaceae - spike mosses!Selaginella eclipes!meadow spike moss !Phylum Lycopodiophyta!Selaginellaceae - spike mosses!Selaginella ruprestis!Rock spike moss !Selaginella selaginoides!Northern spike moss!Endangered! !Phylum Lycopodiophyta!Isoetaceae - quillworts!1 genus and about 150 species; worldwide; 2 spp. in WI - Isoetes echinospora most common!!Aquatic or semi-aquatic plants with corm-like stems with secondary growth. Absorb carbon through their roots.!Leaves with ligules and quite long (15+ cm) for microphylls.!Isoetes echinospora!I. butleri - not native!7!Phylum Lycopodiophyta!Isoetaceae - quillworts!Heterosporous plants with sporangia borne at the base of sporophylls which are similar to vegetative leaves. Megasporangia + microsporangia!Phylum Polypodiophyta - ferns & horsetails!Equisetaceae - horsetails, scouring rushes [previously placed in own phylum - Equisetophyta]!1 genus, Equisetum, 15 species with a cosmopolitan distribution except for Australia or New Zealand [9 species in Wisconsin]!Plants are primarily colonizers of unforested areas, lake margins and wetlands!Shoots monomorphic or dimorphic (see right).!!Often highly branched (horsetails) appearing like leaves. Others not branched (scouring