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Topic 03 Overview of Taxa Lecture Reading: 1. Plate 1. Reproductive Terminology (pp 978-979) in Rhoads & Block (2007). 2. Plate 2. Terminology (pp 980-981) in Rhoads & Block (2007). 3. Rhoads & Block (2007) descriptions of all PA-native plant families mentioned. 4. Angi osperm Phy logeny Group. 2009. An up da te o f the Ang iosperm Phylogeny Group classification for the orders and families of flowering : APG III.

I. & allies ()

•Vascular •Rhizomatous / Stoloniferous •Water needed for fertilization •Free-sporing (lack )

I. Ferns & fern allies (pteridophytes) A. Club-, , or lycopods

Lycopodiaceae • Microphylls • Dichotomous branching • Sporangia in strobilus typical

Lycopodium

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I. Ferns & fern allies (pteridophytes) A. Club-mosses, Lycophytes, or lycopods

Lycopodiaceae • Microphylls • Dichotomous branching • Sporangia in strobilus typical

Diphasiastrum

I. Ferns & fern allies (pteridophytes) A. Club-mosses, Lycophytes, or lycopods

Lycopodiaceae • Microphylls • Dichotomous branching • Sporangia in strobilus typical

Huperzia

I. Ferns & fern allies (pteridophytes) B. Horsetails & Scouring-Rushes

Equisetaceae • Minute microphylls in whorls • Nodal, whorlar branching • Hollow, ribbed stems • Silicaceous stems • Sporangia in strobilus

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I. Ferns & fern allies (pteridophytes) C. Leptosporangiate Ferns Equisetum lato • Macrophylls (typically pinnate) • Circinate • Branching variable • Sporangia in (plural sori) • Leptosporangia

I. Ferns & fern allies (pteridophytes) D. Whisk-Ferns

Psilotaceae • Rootless • Microphylls or enations • Branching dichotomous • Sporangia in synangium (plural synangia)

Psilotum

Tmesipteris

E. Phylogeny of Vascular plants

Xylem & ; dominant; Dichotomous branching of Club-mosses, lycophytes

Ferns, horetails, & whisk-ferns (Microphylls); ; Clustered sporangia Macrophylls , plants

Seeds; ; Eustele; Vascular Cambium ()

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E. Phylogeny of Vascular plants

Hollow internodes; Ribbed stem; Interaxillary branching with whorled phyllotaxy horsetails, scouring-rushes

whisk-ferns LfllftLoss of lvs; loss of roots; synangia Stelar characters Leptosporangiate ferns

Leptosporangia

II. Seed plants (spermatophytes)

• Eustele & vascular cambium (except in monocots) • Macrophylls • Branching axillary (excep in ) • retained, develop on parent sporophyte • Pollen (external water not required for fertilization) • and Seeds

II. Seed plants (spermatophytes) A.

• Ovules exposed at , seeds naked

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II. Seed plants (spermatophytes) A. Gymnosperms 1. Cycads • Mostly unbranched, evergreen or with terminal of pinnate lvs. • Circinate vernation • • Branching, when present, dichotomous or adventitious • Dioecious • Male sporangia in strobilus

II. Seed plants (spermatophytes) A. Gymnosperms Zamiaceae (e.g., Zamia) 1. Cycads Cycadaceae (Cycas)

II. Seed plants (spermatophytes) A. Gymnosperms 2. Ginkgoaceae () • Branched, deciduous trees w/ fan-shaped lvs on short • Leaf venation dichotomous • Dioecious • Male sporangia in pendulous strobilus • Ovules on forked, pendulous pedlduncle

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II. Seed plants (spermatophytes) A. Gymnosperms 3.

• Trees or shrubs with needle-like or scale-like lvs • Mostly evergreen • canals • Dioecious or monoecious • Male sporangia in strobilus • Ovules on branched strobilus called a “cone”

II. Seed plants (spermatophytes) A. Gymnosperms 3. Conifers Male strobili Female cone

II. Seed plants (spermatophytes) A. Gymnosperms 3. Conifers Male strobili Female cone

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II. Seed plants (spermatophytes) A. Gymnosperms 3. Conifers

Pinaceae (pine ) Cupressaceae (Cypress family) •Lvs needle-like •Lvs needle- or scale-like •Flat, spiraled cone scales •Peltate, opposite cone scales •Seeds large, unilateral wing, 2 per scale •Seeds small, equilateral wing, >2 per scale

II. Seed plants (spermatophytes) A. Gymnosperms 3. Conifers

Taxaceae (yew family) •Lvs needle-like •Small cone with 1-fertile scale w/ 1 seed •Fleshy aril from funiculus

Taxus

II. Seed plants (spermatophytes) B. Angiosperms or flowering plants •Ovules concealed by carpels comprising pistil(s) at pollination seeds in •“” •Plants variable in

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