The Monocots: Part 1 Overview, Basal, and “Petaloid” Groups Spring 2014.
-
Upload
maria-nichols -
Category
Documents
-
view
216 -
download
0
Transcript of The Monocots: Part 1 Overview, Basal, and “Petaloid” Groups Spring 2014.
Synapomorphies of Monocots
• Root system adventitious • One cotyledon • Stems with scattered vascular bundles (no
secondary growth); herbaceous• Leaves parallel-veined with a sheathing
base• Flowers pentacyclic (5 whorls), trimerous • Sieve tube member plastids with several
cuneate protein crystals• Lots of molecular support for monophyly
Monocot charactersScattered vascular bundles in stem
– numerous; actually complex organization– no vascular cambium (a few weird exceptions)
Monocot charactersLeaves:
– parallel venation in most monocots [may be reversals with net-venation!]
– sheathing base
Trillium
Smilax
Monocot characters
• Pentacyclic, trimerous flowers with 2 perianth whorls and 2 whorls of stamens and the gynoecium as 1 whorl
Monocot characters
Cuneate protein bodies in sieve cell plastids– “wedge-shaped” inclusions– function unknown
Additional features of monocots
• Leaves formed from the basal end of the leaf primordium
• Usually with monosulcate pollen• Lack glandular teeth on leaves
How many monocots?
• ca. 3,000 genera• ca. 65,000 species • 22-25% of angiosperms• Include:
-aroids-bananas-lilies-gingers-orchids (20,000+ spp.)-irises-palms-grasses (11,000+ spp.)
Phylogeny of Monocot Groups
AcoralesAlismatalesLilialesAsparagalesDioscorealesPandanalesArecalesPoalesCommelinalesZingiberales
Basal“Petaloid”Commelinid
Basal and “Petaloid” Monocot Groups
Order AcoralesAcoraceae
Order AlismatalesAraceae*
Alismataceae
Order LilialesLiliaceae*
Order AsparagalesAgavaceae Alliaceae*AmaryllidaceaeIridaceae*Orchidaceae*
*required families
Basal Monocots:
Acorales: Acoraceae
• Widespread, temperate throughout tropical regions
• Aquatic herb• Diversity: 1-3 spp. in 1 genus (Acorus)• Flowers: typical of Araceae, coalesced into a
spike-like spadix• Significant features: Sister to the rest of the
monocots; contain ethereal oils.• Special uses: none• Family not required, but Acorus
evolutionarily important
“Petaloid” Monocots—Alismatales:
Araceae(The Arum Family)
• Cosmopolitan; greatest diversity in tropical regions• Mainly terrestrial and some aquatic herbs, vines,
epiphytes, floating aquatics• Diversity: 3,300 species, 104 genera• Flowers: many, small; lacking extensive perianth,
carpels 2-3; if unisexual then spatially separated in inflorescence or sometimes plants dioecious
• Significant features: inflorescence – spadix subtended by a spathe (specialized leaf)
• Special uses: many ornamentals; Colocasia as food• Required family
Araceae—Arisaema
Arisaema triphyllumJack-in-the-pulpit
Arisaema dracontiumgreen dragon
-Jack-in-the-pulpit is one of our common spring wildflowers
Arisaemasikokianum
Amorphophallus (Corpse flower)
http://www.youtube.com/watch?v=FHaWu2rcP94
Araceae: Lemna and friends
Lemna ~ duckweed
• Reduced plant body: no stem or leaves; sometimes no roots• Rarely flower
Alismatales: Araceae
Economic plants and products:
Colocasia esculenta• Taro “root” or dasheen“poi”
• 10% of the world uses as staple (starch) in diet
“Petaloid” Monocots—Alismatales:
Alismataceae(The Water Plantain Family)
• Widely distributed• Aquatic & wetland rhizomatous herbs• Number of species: 88 species, 15 genera• Flowers: sepals & petals distinct, many
apocarpous carpels; flowers or floral axes often whorled
• Significant features: rhizomatous• Special uses: ornamental aquatics• Family not required
Phylogeny of Monocot Groups
AcoralesAlismatalesLilialesAsparagalesDioscorealesPandanalesArecalesPoalesCommelinalesZingiberales
Basal“Petaloid”Commelinid
“Petaloid” Monocots—Liliales:
Liliaceae(The Lily Family)
• Widely distributed in temperate regions of the Northern Hemisphere
• Perennial herbs, usually with bulbs and contractile roots
• Number of species: ca. 600 species, in 16 genera
• Flowers: tepals 6, distinct, carpels 3, stamens 6
• Significant features: Fruit a loculicidal capsule, sometimes a berry; no onion-like odor
• Special uses: many ornamentals• Required family
Tulipa-scapose herbs from tunicate bulbs-leaves 2-several on a stem-perianth campanulate to cuplike -tepals 6, erect-stigma prominently 3-lobed
Phylogeny of Monocot Groups
AcoralesAlismatalesLilialesAsparagalesDioscorealesPandanalesArecalesPoalesCommelinalesZingiberales
Basal“Petaloid”Commelinid
Asparagales vs. Liliales
• Herbs; not succulent• Tepals often spotted• Nectaries at base of tepals/filaments• Styles 1 (trifid) or 3• Seed coat present• No phytomelan crust (seeds not black)
• Herbs to woody; sometimes succulent• Tepals not spotted• Nectaries septal• Style usually 1, simple• Seed coat collapsed to + present• Phytomelan crust (seeds black) from dry fruits; not in fleshy fruit
“Petaloid” Monocots—Asparagales:
Alliaceae(Onion Family)
• Widely distributed in temperate and tropical regions; also semiarid.
• Bulb-forming herbs with basal, usually narrow leaves
• Number of species: ca. 600 species, in 13 genera• Flowers: Often showy, tepals 6, stamens 6, 3
connate carpels, ovary superior; inflorescence umbellate; fruit a loculicidal capsule.
• Significant features: sulfur-containing compounds (onion odor)
• Special uses: onion, garlic, leek, shallots, chives, used as food & seasonings; ornamentals
• Required family
“Petaloid” Monocots—Asparagales:
Iridaceae(The Iris Family)
• Widespread in tropical and subtropical regions; absent in Australia.
• Perennial herbs forming rhizomes, corms, or bulbs• Number of species: ca. 1,750 species, 67 genera• Flowers: radial or bilateral, showy; tepals 6, outer
tepals often differentiated from inner; stamens (2) 3, opposite outer tepals; carpels 3, fused into an inferior ovary; fruit a loculicidal capsule
• Significant features: leaves unifacial or terete, equitant
• Special uses: many ornamentals; saffron (Crocus sativus)
• Required family
Iris (Greek for rainbow)
-style branches broad, petaloid, terminating in paired crests -anthers appressed to style branches
“Petaloid” Monocots—Asparagales:
Orchidaceae(The Orchid Family)• Widespread throughout the world; maximal diversity in
tropical regions• Primarily epiphytes; some terrestrial herbs, occasionally vines• Diversity: ca. 20,000 species in 700-800 genera• Flowers: showy, usually resupinate, bilateral, the median inner
tepal differentiated into a labellum (lip); highly modified androecial and gynoecial parts, fused into a column; pollen grouped into soft or hard masses (pollinia) united by a stalk into a pollinarium; ovary inferior; placentation parietal; fruit a capsule dehiscing with (1-)3 or 6 slits; seeds tiny, dust-like
• Significant features: among the most specialized of all angiosperm flowers
• Special uses: many ornamentals; Vanilla• Required family
http://www.youtube.com/watch?v=wmgKABRCZpo&feature=related
Richard Dawkins talking about orchid pollination
Morgan’s Sphinx Moth
Endemic toMadagascar
http://www.youtube.com/watch?v=OMVN1EWxfAU
Asparagales: Orchidaceae
Economic plants and products:
Vanilla flavoring extracted from immature capsules
of Vanilla planifolia
Asparagales: Agavaceae
Economic plants and products:
• Fiber for rope from species of Yucca and Agavee.g., sisal hemp