Diversity and EvolutionDiversity and Evolutionof Monocotsof Monocots. . . orchids and palms . . .. . . orchids and palms . . .4 main groups:4 main groups:•• Acorales Acorales - sister to all monocots- sister to all monocots•• AlismatidsAlismatids–– inc. Aroids - jack in the pulpitinc. Aroids - jack in the pulpit•• Lilioids Lilioids (lilies, orchids, yams)(lilies, orchids, yams)–– grade, non-monophyletic grade, non-monophyletic–– petaloidpetaloid•• Commelinoids Commelinoids–– Arecales Arecales –– palms palms–– Commelinales Commelinales –– spiderwort spiderwort–– Zingiberales Zingiberales ––bananabanana–– PoalesPoales–– pineapplepineapple–– grasses & sedges grasses & sedgesLilioidsLilioids - - petaloid petaloid monocots monocotsLilioids - petaloid monocotsLilioids - petaloid monocots1. 1. Terrestrial/epiphytesTerrestrial/epiphytes: plants: plantstypically not aquatictypically not aquatic2. 2. GeophytesGeophytes: herbaceous above: herbaceous aboveground with below groundground with below groundmodified perennial stems: bulbs,modified perennial stems: bulbs,corms, rhizomes, tuberscorms, rhizomes, tubers3. 3. TepalsTepals: showy : showy perianthperianth in 2 in 2series of 3 each; usually allseries of 3 each; usually allpetaloidpetaloid, or outer series not, or outer series notgreen and sepal-like & with green and sepal-like & with nonobractsbractsAsparagales: *Orchidaceae - orchidsAsparagales: *Orchidaceae - orchids•• finish the finish the AsparagalesAsparagales by bylooking at the largest family -looking at the largest family -the orchidsthe orchids*Orchidaceae - orchids*Orchidaceae - orchidsOrchids areOrchids aremycotrophicmycotrophic (= fungi (= fungidependent) dependent) lilioidslilioids;;some are obligatesome are obligatemycotrophsmycotrophsCypripedium acauleCypripedium acauleStemless lady-slipperStemless lady-slipperCorallorhiza striataCorallorhiza striataStriped coral rootStriped coral rootThe family is diverse with about 880 genera and over 22,000The family is diverse with about 880 genera and over 22,000species, mainly of the tropicsspecies, mainly of the tropicsAll orchids have a All orchids have a protocormprotocorm - a feature restricted to the - a feature restricted to thefamily.family.Dactylorhiza majalisDactylorhiza majalis protocorm protocorm*Orchidaceae - orchids*Orchidaceae - orchids•• structure formed after germination and before the structure formed after germination and before thedevelopment of the seedling plantdevelopment of the seedling plant•• has no radicle but instead mycotrophic tissue has no radicle but instead mycotrophic tissueIonopsisIonopsis twig twigepiphyteepiphyteDendrobiumDendrobium branch branchepiphyteepiphyte*Orchidaceae - orchids*Orchidaceae - orchidsCosmopolitan, but the majority of species are found in theCosmopolitan, but the majority of species are found in thetropics and subtropics, ranging from sea level to almost 5000 mtropics and subtropics, ranging from sea level to almost 5000 min nearly all environments except open water and true desert.in nearly all environments except open water and true desert.Habit varies from herb to vine, but moreHabit varies from herb to vine, but morethan half of the species are than half of the species are epiphyticepiphyticOncidiumOncidium trunk trunkepiphyteepiphyteOrchid root Orchid root velamenvelamen (water storage)(water storage)leaf tubersleaf tubers (water storage) (water storage)*Orchidaceae - orchids*Orchidaceae - orchidsSurvive in these epiphytic and other harsh environments viaSurvive in these epiphytic and other harsh environments viaCAMCAM photosynthesis, photosynthesis, velamenvelamen, and , and leaf tubersleaf tubers, in addition to, in addition tomycorrhizal associationmycorrhizal associationSpecialized reproductive biology:Specialized reproductive biology:**OrchidaceaeOrchidaceae - orchids - orchidsEulaemaEulaema (euglossine) (euglossine)Perfume industryPerfume industryOphrysOphrys•• unusual unusual pollination systemspollination systems•• labellumlabellum petal for landing platform petal for landing platform•• pollenpollen masses, masses, reduced stamenreduced stamen number number•• numerous, numerous, dust-like seedsdust-like seedsBulbophyllumBulbophyllum nocturnumnocturnumOnly totally night bloomingOnly totally night bloomingorchidorchidFungal midge pollinated?Fungal midge pollinated?A 2007 paper in NatureA 2007 paper in Naturesuggests that the orchidsuggests that the orchidfamily is not recent, butfamily is not recent, butof late Cretaceous originof late Cretaceous origin**OrchidaceaeOrchidaceae - orchids - orchids*Orchidaceae - orchids*Orchidaceae - orchidsCA 3 COZ 2+1 A 3,2,1 G (3)CA 3 COZ 2+1 A 3,2,1 G (3)——•• 6 tepals with 6 tepals withlabellum labellum (flower(flowerresupinateresupinate or orupside down)upside down)•• 3 or fewer 3 or fewerstamensstamens•• inferior inferiorgynoecium fusedgynoecium fusedat top withat top withstamens to formstamens to formcolumncolumn•• capsule capsule*Orchidaceae - orchids*Orchidaceae - orchidsFive subfamiliesFive subfamilies3 stamens3 stamens2 stamens2 stamens1 stamen1