9/18/2014 Topic 03 Overview of Plant Taxa Lecture Reading: 1. Plate 1. Reproductive Terminology (pp 978-979) in Rhoads & Block (2007). 2. Plate 2. Leaf Terminology (pp 980-981) in Rhoads & Block (2007). 3. Rhoads & Block (2007) descriptions of all PA-native plant families mentioned. 4. Ang iosperm Phy logeny Group. 2009. An up da te o f the Ang iosperm Phylogeny Group classification for the orders and families of flowering plants: APG III. I. Ferns & fern allies (pteridophytes) •Vascular •Rhizomatous / Stoloniferous •Free-sporing (lack seeds) with free-living gametophytes •Water needed for fertilization I. Ferns & fern allies (pteridophytes) A. Club-mosses, lycophytes, or lycopods Lycopodiaceae • Microphylls • Dichotomous branching • Sporangia (sing. sporangium) in strobilus (pl. strobili) typical Lycopodium 1 9/18/2014 I. Ferns & fern allies (pteridophytes) A. Club-mosses, lycophytes, or lycopods Lycopodiaceae • Microphylls • Dichotomous branching • Sporangia (sing. sporangium) in strobilus (pl. strobili) typical Diphasiastrum I. Ferns & fern allies (pteridophytes) A. Club-mosses, lycophytes, or lycopods Lycopodiaceae • Microphylls • Dichotomous branching • Sporangia (sing. sporangium) in strobilus (pl. strobili) 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 Equisetum 2 9/18/2014 I. Ferns & fern allies (pteridophytes) C. Leptosporangiate Ferns Equisetum Polypodiaceae sensu lato • Macrophylls (typically pinnate) • Circinate vernation • Branching variable • Sporangia in sorus (pl. sori) • Leptosporangia I. Ferns & fern allies (pteridophytes) D. Whisk-Ferns Psilotaceae • Rootless • Microphylls or enations • Branching dichotomous • Sporangia in synangium Psilotum Tmesipteris E. Phylogeny of Vascular plants 1. Xylem & 2. Phloem; Rhyniophytes † 3. Sporophyte dominant; 4. Branched sporophytes Club-mosses, lycophytes Ferns, horetails, & whisk-ferns 1. Leaves; 2. Roots; 3. Clustered sporangia 1. Macrophylls (lost in modern horsetails and whisk-ferns) spermatophytes, seed plants 1. Ovules/Seeds; 2. Pollen; 3. Eustele; 4. Vascular Cambium (wood) 3 9/18/2014 Angiosperms (vesseled seeds) Gymnosperms (naked seeds) Seed Plants Lycopods Native Ferns & Horsetails II. Seed plants (spermatophytes) • Eustele & vascular cambium (except in monocots) • Macrophylls • Branching axillary (except in cycads) • Spores retained, gametophytes develop on parent sporophyte • Pollen (external water not required for fertilization) • Ovules and Seeds II. Seed plants (spermatophytes) A. Gymnosperms • Ovules exposed at pollination, seeds naked 4 9/18/2014 II. Seed plants (spermatophytes) A. Gymnosperms 1. Cycads • Mostly unbranched, evergreen trees or shrubs with terminal rosette of pinnate lvs. • Circinate vernation • Cataphylls • 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. Ginkgos Ginkgoaceae (Ginkgo) • Branched, deciduous trees w/ fan-shaped lvs on short shoots • Leaf venation dichotomous • Dioecious • Male sporangia in pendulous strobilus • Ovules on forked, pendulous pedlduncle 5 9/18/2014 II. Seed plants (spermatophytes) A. Gymnosperms 3. Conifers • Trees or shrubs with needle-like or scale-like lvs • Mostly evergreen • Resin 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 6 9/18/2014 II. Seed plants (spermatophytes) A. Gymnosperms 3. Conifers Pinaceae (pine family) 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 7.