K: Plantae Div: Sphenophyta“horsetails or scouring rushes”

Evolved during the Devonian Period (395 mya); one of the dominants during the Caboniferous Period.(345-280 mya).

K: Plantae Div: Sphenophyta“horsetails or scouring rushes”

1. Silica in cell walls. 2. Leaves microphyllous; small and scalelike; form whorls at

nodes. 3. Vegetative and fertile shoots. 4. Large sporophyte (2n) & small gametophyte (n) - both independent. 5. Extensive rhizomes with roots that branch irregularly. 6. All branching (leaves & roots) whorled at nodes. 7. Growth from the base of each segment (intercalary). 8. Are homosporous.

K: Plantae Div: Sphenophyta“horsetails or scouring rushes”

Intercalary meristem– adds length to the internodes

K: Plantae Div: Sphenophyta“horsetails or scouring rushes”

K: Plantae Div: Sphenophyta“horsetails or scouring rushes”

*All of the silicified cells are in the epidermis. *Stomates of epidermis sunken in E. hymanale. *Carinal canals for water conduction. *Central canal and vallecular canals for gas exchange. Endodermis

– outside layer around stele

Pericycle– single cell layer just inside of endodermis– gives rise to branch roots

K: Plantae Div: Sphenophyta“horsetails or scouring rushes”

Reproduction: homosporous

K: Plantae Div: Sphenophyta“horsetails or scouring rushes”

Reproduction: homosporous sporangiophore and sporangia

K: Plantae Div: Sphenophyta“horsetails or scouring rushes”

Reproduction: homosporous tapetum and tapetal plasmodium

K: Plantae Div: Sphenophyta“horsetails or scouring rushes”

Reproduction: homosporous green spores germinate quickly.

K: Plantae Div: Sphenophyta“horsetails or scouring rushes”

Reproduction: homosporous spores with elators

K: Plantae Div: Sphenophyta“horsetails or scouring rushes”

Reproduction: homosporous green spores germinate quickly.

K: Plantae Div: Sphenophyta“horsetails or scouring rushes”

Reproduction: homosporous meiosis spores (n) germinate ----------> gametophyte (n)

2 types of gameophytes: male and monoecious antheridia & archegonia

K: Plantae Div: Sphenophyta“horsetails or scouring rushes”

Reproduction: homosporous fertilization --> zygote (2n) --> sporophyte (2n)

K: Plantae Div: Psilophyta“Whisk Ferns”

Evolved during the late Devonian Period (approx. 375 mya)

K: Plantae Div: Psilophyta“Whisk Ferns”

1. Plant Body (2n) composed of thin dichotomously branched aerial stems and rhizomes with ridges and pentagonal in x-section.

2. No roots but have rhizoids with micorrhiza.

K: Plantae Div: Psilophyta“Whisk Ferns”

1. Plant Body (2n) composed of thin dichotomously branched aerial stems and rhizomes with ridges and pentagonal in x-section.

2. No true roots but have rhizoids with micorrhiza. 3. Bears small leaf-like appendages, or prophylls. (no vascular tissue but leaf traces) 4. Spores (n) are produced in trilobed structures on the tips of

short branches called synangia.

K: Plantae Div: Psilophyta“Whisk Ferns”

4. Spores (n) are produced in trilobed structures on the tips of short branches called synangia.

tapetal plasmodium sporangial wall

K: Plantae Div: Psilophyta“Whisk Ferns”

Psilophyte spores (n) are kidney-shaped.

K: Plantae Div: Psilophyta“Whisk Ferns”

Psilophyte spores (n) are slow to develop into monoecious gametophytes (n).

archegonia

K: Plantae Div: Psilophyta“Whisk Ferns”

Psilophyte spores (n) are slow to develop into monoecious gametophytes (n).

antheridium

K: Plantae Div: Psilophyta“Whisk Ferns”

Development from the fertilized egg (zygote 2n) proceeds in the archegonium.

K: Plantae Div: Psilophyta“Whisk Ferns”

Eventually the young sporophyte (2n) becomes the mature plant body (2n).

K: Plantae Div: Psilophyta“Whisk Ferns”

Stem and rhizome development: immature stem tip - promeristem, protoderm, ground

meristem, procambium

K: Plantae Div: Psilophyta“Whisk Ferns”

Mature stem -

K: Plantae Div: Psilophyta“Whisk Ferns” Genus: Tmesipteris