Seedless Vascular Seedless Vascular PlantsPlants

Lycopodiophyta: LycophytesPteridophyta: Ferns

4 orders of true ferns + Psilotales: Whisk ferns

Equisetales: Horsetails

Characteristics of the Seedless Characteristics of the Seedless Vascular PlantsVascular Plants

Vascular tissues (protostele, siphenostele, few have eustele) Well developed cuticle Lignin & cellulose in secondary wall Protected Sporangia In most, sporangia are aggregated into strobili Have dominant sporophytes Require water for fertilization

Leaves in the Seedless V. P.Leaves in the Seedless V. P.

Enations: scale-like outgrowth devoid of vascular tissues Microphylls: evolved from enations, with a single vein Megaphylls: evolved as modified branches, have branched veins

Phylum Lycopodiophyta: Phylum Lycopodiophyta: LycophytesLycophytes

Mostly tropical Consist of 3 living orders each with a single

family All living genera are herbs with microphylls

Club Mosses: Club Mosses: F. LycopodiaceaeF. Lycopodiaceae

Example: The genus Lycopodium * All living genera, except two, are classified in this

family Seven genera are represented in U.S. & Canada but most

species are tropical & epiphytes Roots & stems are protostelic Homosporous, sporangia are in axils of fertile leaves

(sporophylls) In Lycopodium, sporophylls are grouped into strobili *

LocopodsLocopods

Lycopodium obscurum Lycopodiella inundata

Lycopodium Lycopodium digitatumdigitatum

An Epiphytic Club MossAn Epiphytic Club Moss

Spike Mosses: Spike Mosses: F. SelaginellaceaeF. Selaginellaceae

One genus Sellaginella (700 species)* Tropical, many found in moist habitats, few

are desert plants Sporophylls arranged in strobili

(Heterosporous)* Has micro- & megasporophylls

Selaginella denticulataSelaginella denticulata

Sporangia Sporangia ((Selaginella underwoodii)Selaginella underwoodii)

http://www.wnmu.edu/academic/nspages2/gilaflora/selaginella_underwoodii.html

SelaginellaSelaginella arbusculaarbuscula

http://zipcodezoo.com/photographers/Charles%20H.%20Lamoureux.asp

SelaginellaSelaginella

Selaginella apoda

Selaginella involvens

Selaginella sppSelaginella spp

Resurrection Plant Resurrection Plant ((Selaginella lepidophyllaSelaginella lepidophylla))

Desert plant: Found in TX, NM, and Mexico

Quillworts: F. IsoetaceaeQuillworts: F. Isoetaceae One genus Isoetes* They are aquatic, or found in seasonally flooded

habitats Plants look like grasses, with underground stem

(corm) All leaves are potential sporophylls Heterosporous, lower leaves are megasporophylls,

upper microsporophylls

Quillworts: Microsporangia & Microspores

Quillworts: Megasporangia & Megaspores

Quillworts: HabitatQuillworts: Habitat

Pteridophyta: Psilotales Psilotales Whisk Ferns Whisk Ferns

Consist of one family & two genera They are the simplest vascular plants Represent an early lineage related to living

ferns

Wisk Fern: Genus Wisk Fern: Genus Psilotum*Psilotum*

Tropical and subtropical in distribution (S. States) Protostelic Lacks roots, has rhizomes & rhizoids Leaves are represented by enations Dominated sporophyte, homosporous Gametophyte is heterotrophic, either symbiotic or

parasitic on soil fungi

PsilotumPsilotum Sporophyte SporophyteSporophyte

Psilotum nudumPsilotum nudum

PsilotumPsilotum nudumnudum

Sporangia

Wisk Fern: Genus Wisk Fern: Genus TmesipterisTmesipteris

Confined to South Pacific Grows as an epiphyte on tree ferns & other plants Has microphylls

Sporangia

http://www.science.siu.edu/landplants/Psilophyta/psilophyta.html

Pteridophyta: Pteridophyta: EquisetalesEquisetales HorsetailsHorsetails

Represented by 1 genus, Equisetum (horsetails)* It is the oldest survivor of plants Widespread in moist habitats and edge of forests Has jointed stem (nodes) & rough texture Has microphylls Homosporous, sporangia are clustered into strobili

Strobilus

Branches

Leaves

Equisetum arvenseEquisetum arvense

Equisetum Equisetum arvensearvense

Equisetum Equisetum hyemalehyemale

Phylum Pteridophyta:Phylum Pteridophyta: True ferns: True ferns:

The largest group of living seedless vascular plants (11,000 spp)

They are found in a variety of habitats 3/4 are tropical 1/3 of tropical ferns grows as epiphytes 1/4 inhabits temperate regions & desert

Polystichum Polystichum acrostichoidesacrostichoides

Dryopteris carthusianaDryopteris carthusiana(mature sporangia)(mature sporangia)

Fern: MorphologyFern: Morphology

Most ferns of temperate region produce annual leaves from subterranean rhizomes

Leaves are megaphylls (fronds), constitute major part of the sporophyte

Ferns are the only seedless vascular plants with megaphylls

Most ferns are homosporous, water ferns are heterosporous

Fern MorphologyFern MorphologyFrond: compound leaf of ferns

Pinnae (leaflet)

Rachis (extension of petiole

Petiole: leaf stalk

Fern SporesFern Spores

Sorus

Fern GametophyteFern Gametophyte

Rhizoid

Archegonia

Antheridia

Fern Life CycleFern Life CycleText Pg. 567

Diversity of FernsDiversity of Ferns

Pteridium aquilinum (Common Brake)

Athyrium filix-femina var. angustum (Lady Fern)

Dryopteris intermedia (Common Wood Fern)

Matteuccia struthiopteris (Ostrich Fern)

Onoclea sensibilis (Sensitive Fern)

Water FernsWater Ferns

Include two orders: Marsileales & Salviniales Constitute the only living heterosporous ferns Marsiliales – Marsilea Salviniales – Salvinia & Azolla

Resembles a four-leaf clover. Grow on mud or submerged with floating leaves

Marsilea spp.Marsilea spp.

Marsilea spp SporocarpMarsilea spp Sporocarp(at base of plants)(at base of plants)

SalviniaSalvinia: Aquatic Habitat: Aquatic HabitatSmall plant, float on surface of water

http://extension.entm.purdue.edu/CAPS/pestInfo/giantSalvinia.htm

Aquatic Fern: Salvinia

Has undivided leaves Plants float freely

http://agspsrv95.agric.wa.gov.au/dps/version02/01_plantview.asp?page=7&contentID=57&

SalviniaSalvinia: Leaf & Hairs: Leaf & Hairs

Hairs protect leaf from getting wet & allow them to remain above water

Aquatic fern: Aquatic fern: AzollaAzolla Weed of the Rice paddies Has bilobed leaves Leaves have pouches that harbor the

nitrogen-fixing bacteria (Anabaeana)

Azolla spp.

Heterocyst

Cyanobacteria such as Nostoc & Anabaena possess a heterocyst where nitrogen fixation takes place

Azolla caroliniana

Azolla caroliniana at Rice Creek Pond (red). The other plants are duckweeds.

Azolla caroliniana on Mud