1	GYMNOSPERMS
2	Gymnosperms – artificial? Today: cycads, conifers, and the Gnetum lineage Monophyly questionable Resolution of relationships requires more extensive sampling 15 families;75-80 genera; 820 species TODAY Many more taxa in the past
3	Gymnosperms All woody, no obligate aquatics, few epiphytes Tracheids, not vessels, in xylem (except Gnetales) Slow to reproduce (up to 1 year between pollination and fertilization; can be two years to cone maturation Usually wind pollinated (but see cycads) Rarely polyploid Dominant in colder and arctic regions
4	Cycads Pinnately compound leaves Trees to 20m tall Ovules/seeds and microsporangia on sporophylls (no true cones) Probably monophyllic Morphology, anatomy, defenses, ecology Retain many primitive features (motile sperm, etc.) NEW Insect pollination – and adaptations Animal dispersal 3 families/10-11 genera/300 species Nowadays mostly S. hemisphere, mostly relictual
5	Cycads Coralloid roots Photo credit: David Webb, http://www.botany.hawaii.edu/faculty/webb/bot410/Roots/CycadNodules.htm Stems with girdling leaf traces and distinctive apical meristems Petioles with omega-like pattern of vascular bundles Leaflets with mucilage canals Origin about 280 million BP Cycasins (poisonous compounds) important as defense against bacteria, fungi, and large animals. Coralloid roots host to cyanobacteria (carryout nitrogen fixation)
6	Cycadaceae Cycas. [Photograph]. Retrieved February 1, 2008, from Encyclopædia Britannica Online: http://www.britannica.com/eb/art-35202 1 genus (Cycas) with about 20 species Stems woody, not or sparsely branched, covered with leaf bases, living leaves near stem apex; sometimes with subterranean stem Leaves persistent, spiral, pinnately compound, circinate vernation Leaflets 1-veined, entire Lower leaflets often reduced and spine-like
7	Cycadaceae (cont.) Photo credits: Top: mherrero, http://www.flickr.com/photos/mherrero/ Bottom: Karlheinz Knock, www.knock1.de Megasporophylls, leaf-like (not clustered into a strobilus) Microsporophylls in compact strobili Pollen nonsaccate, single furrow Often fire resistant Forests and savannas (Australia, Madagascar, SE Asia, Polynesia)
8	Zamiaceae Photo credit: http://www.sci.muni.cz/bot_zahr/fototexty/druhy%20foto.htm Leaves with or without spines Vernation not circinate Leaflets with numerous veins, no clear midvein 8 genera/111 species (Zamia, Encephalartos, Dioon)
9	Zamiaceae (cont.) Sporophylls aggregated into strobili Microsporophylls often in clusters Megasporophylls 1-several/plant, 2 ovules Pollen as in Cycadaceae New World, Africa, Australia; grasslands, woodlands and tropical forests (1 species – Zamia floridana – native to U.S.) Often cultivated A source of Sago (after glycoside removal) Photo credit: Jack Scheper, Floridata.com Top photo – male; bottom photo female
10	Stangeriaceae Stem essentially subterranean Leaflets with midveins and dichotomously branching secondary veins Ovules/seeds in strobilus 1 genus, 1 species
11	Coniferales Largest group of conifers Most ecologically and economically important USUALLY seeds in cones – consisting of an axis and highly modified short shoots (scales), scales are subtended by bracts (fused to the scale in Cupressaceae and Araucariaceae) Origin about 300 mBP Most modern families present by the late Triassic Important in colder regions Valuable as ornamentals & sources of wood (paper, building material, etc.)
12	Coniferales (cont.) Wind pollinated Pollination droplets, pollen tube Slow sperm, not flagellate Often monopodial with dominant central shoot Leaves usually whorled when young) Seeds polycotyledonous 7 families/60-65 genera/600+ species
13	Pinaceae Photo credit: Dave Powell, USDA Forest Service, Bugwood.org Trees, occasionally shrubs Often fragrant (bark and/or lvs) Resin canals present in wood and lvs Leaves simple, linear, spirally arranged, usually persistent Cone scale bracts free 10 genera/ 220 species (Pinus, Picea, Tsuga, Abies, Larix, Cedrus) Almost entirely Northern Hemisphere; 6 genera widespread, 4 genera narrowly distributed
14	Cupressaceae: EXPANDED Photo credit: Richard Carter, Valdosta State University, Bugwood.org Includes old Taxodiaceae 29-32 genera/110-130 species; 16 genera monotypic; Metasequoia, Taxodium & Glyptostrobus are deciduous Trees or shrubs; wood and foliage often aromatic Bark tending to shred in long fibers or breaking into blocks at maturity Leaves scale-, awl-, or needle-like; opposite or spirally arranged; persistent after dying.
15	Cupressaceae (cont.) Pollen non-saccate Cone scales spiral or opposite, flat or peltate, fused to bract, (juicy in Juniperus) Seeds 2-3-winged or wingless, wing from seed coat, 1-20/scale, maturing in 1-3 yrs Wood often fragrant; many genera are highly sought after commercial species for timber, perfumes & flavoring (Juniperus – Gin). Common name cedar is given to many gymnosperms with fragrant wood Photo credit: Chris Evans, River to River CWMA, Bugwood.org
16	Cupressaceae - Juniperus Leaves opposite or ternate, acicular or scale-like Ovulate cones composed of 3-8 fused scales, Scales fleshy at maturity Widely cultivated in western U.S. Photo credit: Mary Ellen (Mel) Harte, Bugwood.org
17	Araucariaceae Long lived trees, to 65 m tall/ 6 m in diameter Conical and symmetrical (especially when young) Highly resinous Lvs simple, entire, varying in shape (awl- or scale-like, linear, oblong or elliptic), spiral or opposite Dioecious or monoecious Pollen not saccate; exine pitted Photo credit: Dennis Haugen, Bugwood.org
18	Araucariaceae (cont.) Photo credit: Dennis Haugen, Bugwood.org Cones solitary, erect (or nearly so), heavy, 2-3 yrs to maturity, scales deciduous; 1 ovule/ scale Valuable lumber and ornamental species. Seeds used for flour In Australia, generally called pines. Wollemia nobilis discovered in Australia in 1994, one of the world’s rarest trees, has mature bark described as looking like bubbling chocolate. Now available as an ornamental.
19	Taxaceae 5 genera/ 20 species Trees to shrubs Not or only slightly resinous Bark scaly or fissured. Lateral branches well developed, similar to leading shoots Leaves simple, linear, flattened, entire, acute, persistent for several years, shed singly, usually spirally attached, often twisted and appearing 2-ranked Dioecious (rarely monoecious) Interesting anatomy Photo credit: Dave Powell, USDA Forest Service, Bugwood.org
20	Taxaceae (cont.) Photo credit: Chris Evans, River to River CWMA, Bugwood.org Pollen not saccate Ovules solitary; cones lacking Seeds with hard outer layer; surrounded by brightly colored aril (outgrowth from beneath ovule, not homologous with epimatium) Torreya provides valuable wood, edible nuts, and oils. Taxus provides furniture grade fine woods and was the preferred wood for long bows; some species are a source of taxol, a cancer-fighting drug.
21	Ginkgoales: Ginkgoaceae Photo credit: Richard Webb, Self-employed horticulurist, Bugwood.org Today: 1 species Ginkgo biloba; more genera & species in past Now all cultivated, fossils much more widespread Tree, to 40 m Resin canals absent Bark – gray, furrowed Long shoots, short shoots Leaves spirally arranged, simple, fan-shaped, bilobed or entire, venation dichotomous
22	Ginkgoales: Ginkoaceae (cont.) Dioecious; XX (female) – XY (male) Pollen strobili on short shoots, long and pendant; pollen not winged Motile sperm Ovules paired, on long stalk from spur shoots Seeds usually 1/stalk, with juicy, stinky outer coat Can live for over 1000 yrs (as can Cycads and Redwoods and …) Photo credits: Paul Wray, Iowa State University, Bugwood.org
23	Podocarpaceae Photo credit: Huntersville, North Carolina; http://www.huntersville.org/interactive%20ordinance/Zoning_TOCshrub.htm 3 genera/ 32 species; mostly Southern Hemisphere Trees or shrubs; to 60 m tall Slightly resinous Dioecious (rarely monoecious) Leaves simple, alternate, persistent, linear to nearly scale-like Pollen usually saccate
24	Podocarpaceae (cont.) Strobilus w/ 1-many ovulate scales; 1 ovule/ scale; scales reduced and fused to ovule, modified into epimatium (fleshy, juicy structure 17 genera/ 170+ species; tropical and subtropical – Southern hemisphere and Old World Valuable for timber Odd shrub (Parasitaxus usta) in New Caledonia lacks roots and parasitizes one of its cousins, Falcatifolium taxoides. Photo credit: R. Van Pelt, May-2005; www.conifers.org/po/po/macrophyllus.htm
25	Gnetales 3 families/3 genera/105 species All three families weird! Show features of both conifers and angiosperms Seeds not enclosed in ovary (conifer feature) Vessels in wood, scales around seed flower-like structures, two sperm nuclei fertilize egg cells (angiosperm features) (but second zygote aborts)
26	Welwitschiaceae 1 genus/ 1 species – Welwitschia mirabilis SW Africa; deserts, mostly restricted to within 200km of coasts in the “fog belt.” Stem: massive short woody, unbranched, becoming a concave disc up to a meter across Leaves 2, strap-like, continue to grow throughout life of plant, tips wearing away and becoming twisted and frayed Pollen and seed strobili on branched stalks arising near leaf bases Photo credit: Botanischer Garten Jena; http://commons.wikimedia.org/wiki/Image:Welwitschia-mirabilis-2.jpg
27	Welwitchiaceae (cont.) Photo credit: Dieter von Willert; http://www.conifers.org/we/index.htm Water is absorbed through odd structures on leaves, mostly from dew. CAM photosynthesis Leaves grow 8-15 cm/yr, suggesting that the oldest known plants are between 500 and 1000 yrs old. Landmines protect plants in Angola, about the only good that comes from land mines
28	Gnetaceae Photo credit: Xiangying Wen One genus, 20-35 species, mostly Asian Primarily lianas, less frequently trees or shrubs Monoecious or dioecious Leaves opposite, elliptic, with reticulate venation and drip tips
29	Gnetaceae Strobili unisexual, in catkin-like formations; Male strobili aggregations of 1-2 sporangia with bracts at base Female strobilus has 1 ovule with 2 integuments and “perianth”. Seeds enclosed in a red, orange, or yellow, fleshy (rarely corky) false seed coat; female gametophyte tissue copious, succulent Many species are edible, with the seeds being roasted, and the foliage used as a leaf vegetable. Some are also valued in herbal medicine Photo credit: Karlheinz Knoch, www.knoch1.de
30	Ephedraceae Photo credit: C.J. Earle, http://www.conifers.org/ep/ep/viridis.htm Erect or climbing shrubs or vines Branches numerous, round, whorled to fascicled, finely longitudinally grooved, internodes 1-10 cm Leaves opposite or whorled, scale-like, fused basally into a sheath, often shed soon after developing Most species dioecious Pollen not saccate
31	Ephedraceae (cont.) Pollination via wind or insects (insect pollinated species produce nectar near the ovaries) Apical ovule encased in a pair of fused bracts Seeds distributed either via wind (bracts with winged keels) or via birds (bracts enlarged, fleshy & juicy) Several species used medicinally to treat cough and circulatory weakness among other ailments Not all species contain epinephrine Photo credit: KK Shrestha, http://www.efloras.org/florataxon.aspx?flora_id=110&taxon_id=111784
32	Pinaceae - Pinus Photo credit: Paul Wray, Iowa State University, Bugwood.org True “pines” Leaves in fascicles of (1)2-5, the FASCICLE round in cross-section, on short shoots from branchlets Cone scales imbricate Seeds terminally winged, 2/scale
33	Pinaceae (cont.) Monoecious Cones w/spirally arranged , flattened bract/scale complexes, bracts free from scale Seeds usually w/long, terminal wing (derived from scale tissue) Quick Fact: Leading source of timber world-wide UT: 4 native genera (as follows)/10 species Photo credit: Dave Powell, USDA Forest Service, Bugwood.org
34	Pinaceae - Picea Leaves sharp, ± square in cross-section, with persistent woody base, the sterigmata Branchlets rough after needle drop because of sterigmata Cones mostly pendent, throughout tree, with relatively thin scales Bark thin, scaly Photo credit: USDA Forest Service - Rocky Mountain Region Archive, USDA Forest Service, Bugwood.org
35	Pinaceae - Abies Photo credit: bugwood.org True firs Bark thin, smooth (except for horizontal resin pockets) Branchlets smooth after needle cast Leaves blunt, flat in cross-section Ovulate cones upright, and restricted to upper 1/3 of tree Cone scales deciduous at maturity
36	Pinaceae - Pseudotsuga “Bark deeply furrowed Branchlets smooth after needle cast Leaves blunt, constricted at base, flat in cross-section Ovulate cones pendent Cone scales retained; bracts conspicuous, 3-pronged Photo credit: Mary Ellen (Mel) Harte, Bugwood.org