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The ANITA grade and the Magnoliid Complex. Spring 2012. Major Angiosperm Clades. Amborellaceae Nymphaeales Austrobaileyales MAGNOLIID COMPLEX MONOCOTS EUDICOTS [TRICOLPATES]. ANITA GRADE. Soltis et al. 2000, APG II 2002, Judd et al. 2002. Angiosperm Evolution: Pollen.
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The ANITA grade and the Magnoliid Complex Spring 2012
Major Angiosperm Clades Amborellaceae Nymphaeales Austrobaileyales MAGNOLIID COMPLEX MONOCOTS EUDICOTS [TRICOLPATES] ANITA GRADE Soltis et al. 2000, APG II 2002, Judd et al. 2002
Angiosperm Evolution: Pollen • Basic division in distinguishing angiosperms is NOT monocotversusdicot!! • Basic distinction is the number of pores or sulcae (grooves) in the pollen grains. • Trends in pollen evolution clearly show a shift from uni-aperturate pollen found in gymnosperms and the “basal” angiosperms to tria-perturate pollen found in the more derived flowering plants. • Plesiomorphic condition in angiosperms is uni-aperturate. • Fossil record is quite good to document this transformation in pollen type.
Fig. 7.1 monoaperturate pollen (one pore or groove)
“Basal” Angiosperms:Amborellaceae (Amborella Family) Amborella trichopoda
“Basal” Angiosperms:Nymphaeaceae(Water Lily Family) Widespread, tropics to temperate regions Aquatic rhizomatous herbs, sap milky Ca. 70 species; 5-6 genera Flowers: many parts; laminar stamens; floating; colorful perianth; beetle pollination syndrome Special uses: ornamentals 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)
Beetle pollination syndrome • Flowers often green or white • Flowers with various but strong scents • Can open during the day or night • Flowers open or enclosed • Nectar and/or pollen reward • See Ch. 13 in Simpson
Major Angiosperm Clades Amborellaceae Nymphaeales Austrobaileyales MAGNOLIID COMPLEX MONOCOTS EUDICOTS [TRICOLPATES] ANITA GRADE Soltis et al. 2000, APG II 2002, Judd et al. 2002
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 or 7 genera, 200 species • Flowers: apocarpous; anthers laminar, large number; receptacle elongated • Significant features: Aromatic; fruit an aggregate of follicles in Magnolia 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
Other Magnoliid families of interest (but not required) • Lauraceae (the laurel or bay family) • Piperaceae (the pepper family) • Aristolochiaceae (the birthwort family)
Magnoliids—Laurales:Lauraceae(Laurel or Bay Family) • Widespread in tropical and subtropical regions; SE Asia & northern South America • Trees, shrubs, vines. • Diversity: 2,200 species, 45 genera • Flowers: concave receptacle that often enlarges in fruit; 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) • Family not required
Lauraceae Enlarged receptacle under the drupe! Cinnamomum cinnamon Sassafras albidum sassafras
Lauraceae Economic plants and products: Cinnamomum zeylandicum True cinnamon
Bird dispersal and ecological role of Lauraceae
Magnoliids—Piperales:Piperaceae • Widely distributed in tropical and subtropical regions. • Primarily herbs; sometimes epiphytic; small trees • Diversity: 3,600 species, 5 genera • Flowers: minute, densely packed in a thick spike or spadix; 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) • Family not required
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 inferior or half-inferior, of 3-6 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. • Family not required
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 • 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
On to the monocots… ...clearly monophyletic…superbly apomorphic! ! !