Poales Poales 4 Main Groups: • Acorales - Sister to All Monocots • Alismatales – Inc

Poales Poales 4 Main Groups: • Acorales - Sister to All Monocots • Alismatales – Inc

Poales Poales 4 main groups: • Acorales - sister to all monocots • Alismatales – inc. Aroids - jack in the pulpit • “Lilioids” (lilies, orchids, yams) cattails, rushes, sedges – non-monophyletic – petaloid • Commelinids – Arecales – palms – Commelinales – spiderwort – Zingiberales –banana – Poales – pineapple – grasses & sedges Poales Poales • showy flowers, Evolutionary trends: • showy flowers, insect or bird insect or bird pollinated • nectar to pollen gathering to pollinated wind pollination • +/- reduced • reduced flowers - loss of • +/- reduced flowers, insect or perianth flowers, insect or wind pollinated wind pollinated • unisexuality sometimes • bracts become important • reduced • reduced flowers, wind • flowers to florets in spikelets flowers, wind pollinated pollinated 1 Poales II: wind pollinated families Xyridaceae - yellow eye grass Small family (5/260) of rush-like leaves with • “grade” centered in the terminal spike of small but showy yellow (or Guayana Shield and blue) petalled-flowers with no nectar. distinctive in tepui-top flora Inflorescence with spirally arranged bracts. • +/- reduced flowers, insect or wind pollinated Xyris difformis Xyris torta - yellow-eyed grass Xyridaceae - yellow eye grass Xyridaceae - yellow eye grass Subfamily with Xyris is widespread and includes Other subfamily is diverse only on Guayana northern hemisphere species. Shield and Brazilian cerrados Abolboideae distribution Xyridoideae (Xyris) distribution Orectanthe Xyris difformis Abolboda 2 Eriocaulaceae - pipewort Eriocaulaceae - pipewort Small family (10/1400) of aquatic Flowers dimerous, unisexual, but emergents, often rosette leaved. crowded together on a bracted, whitish terminal head of an elongated Primarily pantropical, centered in scape - “pipebrush” inflorescence Guayana Shield and Brazilian cerrados, with 1 species in Great Various Eriocaulon - Lakes. pipeworts Eriocaulon - pipewort Eriocaulaceae - pipewort Poales II: wind pollinated families • look at cattails and bur- reeds - one of 3 separate shifts to reduced flowers and wind pollination Paepalanthus • one family now Brazilian cerrados (Typhaceae) Rhodonanthus Roraima tepui • reduced flowers, wind pollinated Syngonanthus Florida sand wetland 3 Typhaceae - cattails Typhaceae - cattails • male flowers essentially 3 stamens • Typhaceae are robust, • female flowers of one carpel with a rhizomatous herbs that like damp conditions and have erect, single seed linear leaves • wind pollinated • terminal cylindrical spike with distinct female flowers below and male flowers above male Typha - cattail female Typhaceae - cattails Typhaceae - cattails Achenes with copious amounts of white hairs near the base of each; wind dispersed T. latifolia X T. angustifolia Typha X glauca - hybrid cattail • the hybrid is invasive and replaces other cattails and other Typha - cattail emergent aquatic plants 4 Typhaceae - bur reeds Typhaceae - bur reeds • rhizomatous, short statured, perennial emergent aquatics • unisexual heads • fruits a head of 1-seeded male achenes female Male flowers essentially 3 stamens plus 3 tepals Female flowers of one-ovuled 3- Sparganium americanum - bur-reed carpellate gynoecium Sparganium americanum - bur-reed Sparganium eurycarpum - giant bur-reed plus 3 tepals. Poales II: wind pollinated families Poales II: wind pollinated families • look at 2 independent • look at 2 independent evolutions of evolutions of “graminoid” habit, “graminoid” habit, reduced flowers, and reduced flowers, and wind pollination wind pollination • 3 families (rush, sedge, grass) • reduced • reduced flowers, wind flowers, wind pollinated pollinated 5 Graminoids: grasses, sedges, rushes *Juncaceae - rushes • largely two genera - Juncus (rush) and Luzula (wood rush) Juncaceae (Rushes) Cyperaceae (Sedges) Poaceae (Grasses) • often tussock forming, leaves usually 3-ranked on round, 3-ranked (in 3 rows): Generally inrolled or round in often partitioned stems Flat, W-shaped in cross- cross-section; hollow or with section, or apparently 2-ranked (in 2 rows), • inflorescence congested, often terminal or appearing lateral Leaves cross-partitions lacking sometimes appearing leafless (you can feel these with your (e.g. in Eleocharis, Juncus - rush fingernail) Schoenoplectus) Margins overlapping or (less Sheaths Margins overlapping Margins fused often) fused A flap of tissue at the A flap of tissue at the junction junction of the sheath and Ligules None of the sheath and blade, not at blade, partly fused to the all fused to the blade blade No scales beneath flowers. Floral 2 surrounding each flower 6-merous perianth (looks a 1 below each flower scales (palea and lemma) little like a lily flower ) Usually bisexual Flowers Bisexual or unisexual Bisexual Three(six)-merous Capsule filled with 3 to many Fruits Achene (a hard nutlet) Grain seeds *Juncaceae - rushes *Juncaceae - rushes • flowers mainly bisexual, reduced and wind pollinated • 6 brownish tepals (lilioid!) surround 6 stamens and superior 3-carpellate ovary Fruit is a 3 to many-seeded capsule. Juncus arcticus - Baltic Juncus effusus - Common rush rush Note rhizome with vertical stems Luzula acuminata Juncus Wood rush tenuis Juncus greenei - Green’s rush Path rush 6 *Juncaceae - rushes *Cyperaceae - sedges 100 genera and 4,500 species primarily of moist habitats. Carex with 2,000 species is one of the largest of all angiosperm genera. Most species have triangular stems in cross section - “sedges have edges” - and thus leaves are 3-ranked. Luzula acuminata - Wood rush Luzula multiflora - Common wood rush *Cyperaceae - sedges *Cyperaceae - sedges Scirpus and relatives (bulrushes) often Cyperus has bisexual flowers: 3 have roundish stems. Florets are bisexual stamens and 2 fused carpels. A single with 3 stamens, 3 fused carpels, 6 bract sits below each floret. The perianth bristles, and 1 subtending bract. spikelets are generally symmetrically Florets are generally whorled in the arranged. spikelet. Cyperus lupulinus- Schoenoplectus tabernaemontani (Scirpus validus) Sand cyperus or sedge Soft-stem bulrush 7 *Cyperaceae - sedges *Cyperaceae - sedges Scirpus (bulrushes) • a mess - polyphyletic! • different species related to other genera (incl. Carex – sedges) Scirpus cyperinus Wool-grass Scirpus atrovirens Daniel Spalink – former Botany Dark green bulrush grad – works on this group Scirpus sp. Jung & Choi 2010 *Cyperaceae - sedges *Cyperaceae - sedges Carex (sedge) is a large, complex, and difficult to key out genus. Sedges have unisexual flowers with the male and female florets usually arranged in discrete portions of the spikelets. Male florets Female florets Carex pensylvanica morphological features! Pennsylvania sedge 8 *Cyperaceae - sedges *Cyperaceae - sedges Both male and female florets are Carex is a genus of roughly 2000 species worldwide, over 150 in subtended by a floret bract. Wisconsin alone. It becomes easier to understand if you think of it in terms of two smaller subgenera: Female florets are further enclosed by a sac-like bract called the perigynium - the achene forms within. achene Carex blanda - Wood sedge Carex intumescens - Bladder sedge Andrew Hipp *Cyperaceae - sedges *Cyperaceae - sedges Other genera . Eriophorum angustifolium cottongrass Carex stricta Tussock sedge A common woodland species Carex pensylvanica Pennsylvania sedge 9 *Cyperaceae - sedges Other genera . Eleocharis ovata - spikerush 10.

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