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The ANITA grade and the Magnoliid Complex. Spring 2010. Basal Angiosperms: Nymphaeaceae (Water Lily Family). Widespread, tropics to temperate regions Aquatic rhizomatous herbs, sap milky 70 species; 8 genera
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The ANITA grade and the Magnoliid Complex Spring 2010
Basal Angiosperms:Nymphaeaceae(Water Lily Family) Widespread, tropics to temperate regions Aquatic rhizomatous herbs, sap milky 70 species; 8 genera Flowers: many parts; laminar stamens; “floating”; colorful perianth; “beetle” syndrome Special uses: ornamentals; sacred lotus Required taxa: Nymphaea (water lily)
Basal Angiosperms:Nymphaeaceae (Water-lily Family) • numerous petals, stamens, carpels • laminar stamens • pollen monosulcate • stigma discoid, radiating • berry-like fruit, dehiscent • perisperm (from the sporophyte) • usually lack vessels (or have tracheid-like vessels)
Basal Angiosperms—Austrobaileyales: Illiciaceae(Star Anise Family) SE Asia, SE USA and Caribbean Trees and shrubs 1 genus, Illicium; ca. 40 species Flowers: many floral parts/tepals; 1 ovule/carpel Special uses: star anise (spice) Required taxa: (none)
Illicium – Star Anise Illicium parviflorum Illiciumfloridanum
Angiosperm Evolution: Pollen • Basic division in distinguishing angiosperms is NOT monocotversusdicot!! • Basic distinction is the number of pores or sulcae in the pollen grains. • Trends in pollen evolution clearly show a shift from uniaperturate pollen found in gymnosperms and the basal angiosperms to triaperturate pollen found in the more derived flowering plants. • Plesiomorphic condition in angiosperms is one sulcus (monocolpate). • Fossil record is quite good to document this transformation in pollen type.
Figure 9.1 from the text, Showing monocolpate to Tricolpate pollen
Magnoliid characters“Magnocots” • 2-ranked leaves, paracytic stomates • Perianth generally 3-merous • Stamens and carpels: distinct, • numerous, spirally arranged • Boat-shaped, monosulcate pollen • Superior ovary • Seeds with fleshy seed coat/aril in many; • minute embryo, copious endosperm • Many anatomical characters (esp. wood)
Magnoliids—Magnoliales:Magnoliaceae(The Magnolia Family) • Temperate to tropical regions of eastern North America; east Asia, South America • Trees or shrubs with simple leaves • Number of species: 2 genera, 220 species • Flowers: apocarpous; anthers laminar, large number; receptacle elongated • Significant features: Aromatic; fruit an aggregate of follicles or winged samaras in Liriodendron • Special uses: ornamentals; timber • Required taxa: Magnolia
Magnoliaceae • solitary flower • elongate receptacle • aggregate of follicles • woody plant • simple leaves • stipules • many spirally arranged parts • separate carpels • laminar stamens Magnolia virginiana sweetbay
Within the family, Magnolia is diagnosed by: -presence of a red or orange fleshy seed coat -follicles opening along the abaxial seam
Magnoliids—Laurales:Lauraceae(Laurel or Bay Family) • Widespread in tropical and subtropical regions; SE Asia & northern South America • Trees, shrubs, vines. • Diversity: 2,500 species, 50 genera • Flowers: concave receptacle; anthers dehiscing via pores with flaps; sticky pollen; pollen without apertures; carpel 1; embryo large, endosperm lacking. • Significant features: ethereal oils • Special uses: cinnamon (Cinnamomum) and bay (Laurus nobilis) used as spices; avocado (Persea) • Required taxon: Sassafras
Lauraceae Cupule under the drupe! Cinnamomum cinnamon Sassafras albidum sassafras
Lauraceae Economic plants and products: Cinnamomum zeylandicum True cinnamon
Magnoliids—Piperales:Piperaceae • Widely distributed in tropical and subtropical regions. • Primarily herbs; sometimes epiphytic; small trees • Diversity: 2,020 species, 6 genera • Flowers: minute, densely packed in thick spikes; noperianth (!); carpels 1-4, connate, with 1 ovule per gynoecium, basal placentation; fruit usually a drupe. • Significant features: stem with bundles in >1 ring or + scattered • Special uses: Piper nigrum (black pepper); Piper betle (betel pepper), ornamentals (Peperomia) • Required taxon: Peperomia
Magnoliids—Piperales:Aristolochiaceae(Dutchman’s Pipe or Birthwort Family) • Widespread in tropical and subtropical regions; absent in Australia. • Lianas or herbs, occasionally shrubs • Diversity: ca. 460 species, 7 genera • Flowers: Highly modified, showy, fused sepals, radial or bilateral, tubular, and S-shaped or pipe shaped calyx tube; corolla usually lacking or vestigial; ovary more or less inferior, of (4-)6 connate carpels; ovules numerous; filaments more or less adnate to style. • Significant features: “dead meat” carrion coloration attracts insects, usually flies. Trap-flowers. • Special uses: ornamentals; some medicinal uses. • Required taxa: Asarum, Aristolochia
Asarum (wild ginger) -stemless perennial with aromatic rhizomes -flowers actinomorphic -filament tips extending beyond the anthers -ovary inferior -fruit a fleshy capsule, seeds large
Characters of Aristolochia(Dutchman’s pipe) • Tropical or warm temperate regions • Perennial herbs or shrubs, twining or climbing or sometimes upright • Calyx tubular, greenish or purplish • Anthers sessile, strongly adnate to the short and fleshy style • “trap” flowers
Ceratophyllaceae -Submerged aquatic with many adaptations for this habitat -Fossil record extends back to the early Cretaceous -Phylogenetic position uncertain, but clearly part of the early radiation of angiosperms above the ANITA grade
On to the monocots… ...clearly monophyletic…superbly apomorphic! ! !
As we venture through the various major groups of angiosperms… Identify the plesiomorphic characteristics associated with particular groups and note their apomorphies (if any) as well. Try to associate “syndromes” of characteristics with each group (make note of special characters occurring together). One good way to study is to write keys to the groups we cover in any given unit. Names of groups are important! Learn to spell and say them! Ask questions!!