The Eudicots, or "true" dicots,
form a monophyletic group. Members share the morphological synapomorphy
of tricolpate pollen or derivitives thereof (the ancestral state of angiosperms, retained by monocots and basal angiosperm lineages, is monosulcate or monoporate pollen). Although most eudicots have flower parts in multiples of 4 or 5, lineages of Eudicots that branched off before the Rosid/Asterid/Caryophyllales split sometimes show ancestral floral characteristics;
these lineages are collectively known as the Basal Eudicots, although they are a paraphyletic group of successive branches (only 2 shown below). They often have
numerous stamens, separate carpels, and other characteristics
more typical of the Basal Angiosperm lineages, and they may have flower parts in multiples of 6 or indeterminate as well as 4 or
5. Some of these plants were once grouped along with the Basal
Angiosperms by traditional taxonomists for these reasons, although
molecular evidence now supports their placement with other true
dicots as does their tricolpate pollen.
families covered in class:
Papaveraceae (Papaveraceae Family)
Ranunculaceae (Buttercup Family)
Papaveraceae: (Poppy Family) ~920 species
Identification characteristics: Papaveraceae have 2 sepals which are soon caducous.
Most have 4 petals that are radially symmetric, but multiples
of 4 also occur. Stamens are numerous in the typical members of the family. Members of the lineage formerly separated as Fumariaceae have highly zygomorphic
or bis-bilaterally symmetric (2 unequal planes of symmetry- see Adlumia and Dicentra) flowers, the petals often being somewhat connivent. Stamens in
typical Papaveraceae are very numerous (6, diadelphous, grouped
in two sets of three in Fumarioids). There is one superior ovary. Papaveraceae
have alternate leaves that may be simple to deeply dissected,
and members outside of Fumariodeae have white to colorful sap.
Interesting stuff: Members of Papaveraceae (including Fumariaceae) produce isoquinone
alkaloids that are often very toxic or otherwise induce profound
physiological effect. The most economically important example
by far is the opium poppy (Papaver somniferum), extracts
of which are the basis for opium, morphine, and other derived
drugs. The seeds of P. somniferum, which contain only
trace amounts of alkaloids, are the poppy seeds commonly used
in baked goods. Many Papaveraceae are colorful garden ornamentals. Note: Fumariaceae are listed as a separate family in your
Argemone albiflora White Prickly-Poppy; Sanguinaria
canadensis (patch), (individual),
(2), (flower closeup), (2), (another patch), (2), (fruit)
closeup), (2), (3), (fruit) Wood
(subfamily Fumarioideae): Adlumia fungosa Allegheny Vine; Corydalis flavula (flower, side), (front), (population) Yellow Fumewort; C.
sempervirens Rock Harlequin; Dicentra
canadensis Squirrel Corn; D. cucullaria (flowers closeup), (habit),
(more habit), (3) Dutchman's Breeches; D. eximia Wild Bleeding-Heart
Ranunculaceae: (Buttercup Family) ~2,377 species
Identification characteristics: Floral morphology in Ranunculaceae is highly variable,
and a suite of characters must be examined for identification.
Species are predominantly herbs (often vines in Clematis).
They have alternate (or basal) leaves (opposite in Clematis).
Usually flowers are radially symmetric (see Delphinium tricorne for an exception). Sepals are usually 5 (4 in Clematis, indeterminant in many others). They are often
petaloid and are the pollinator attractant when petals are absent.
Sometimes a combination of sepals and petals make up the colorful
floral display (see Delphinium). Petals are usually 5
when present, and may have nectar glands at their base, sometimes
held within an elaborated spur (see Delphinium and Aquilegia canadensis below for examples). Stamens are
numerous in all cases. Ovaries are superior and apocarpous (separate),
sometimes 5, often more numerous. An important characteristic
in keys is whether each carpel contains one or numerous ovules,
and thus forms an achene or follicle, respectively. Some multi-ovule
carpels occasionally form berries rather than follicles.
Interesting stuff: Like other Ranunculalean families, Ranunculaceae often produce
very toxic alkaloids. The family provides numerous ornamentals,
such as Larkspurs (Delphinium), Monkshoods (Aconitum),
Columbines (Aquilegia), and Windflowers (Anemone).
Some Ranunculaceae have reduced perianth parts and rely instead
on brightly colored stamens to attract pollinators (see Hydrastis
canadensis and Thalictrum pubescens). Occasionally,
Ranunculaceae are dioecious (see Clematis virginiana and Thalictrum dioicum) and/or wind pollinated (T. dioicum).
Most Ranunculaceae bloom in spring and make up
a significant portion of the spring flora in the eastern U.S.
Examples: Aconitum columbianum Western Monkshood; A. reclinatum Trailing Monkshood; Actaea alba, (inflorescence)
(infructescence) White Baneberry; Anemonella
(Thalictrum) thalictroides, (2), (3), (4), (pink form)
Rue Anemone; Anemone multifida Cut-leaved Anemone; A. quinquefolia Wood Anemone; A. virginiana, (flower closeup)
(flower 2), (flower 3) Wild Columbine; Caltha palustris Marsh Marigold; Cimicifuga racemosa Black Cohosh; Clematis occidentalis, (flower) Purple
Clematis; C. ochroleuca Curlyheads; C. pitcheri, (flower) Texas Leatherflower
(photo from TX), C. viorna Leatherflower; C.
virginiana (male) Virgin's Bower; Coptis groenlandica, (closer) Goldthread; Delphinium carolinianum (2), (3) Prairie Larkspur; D.
tricorne (2), (3), (flower) Dwarf Larkspur; Hepatica
americana (white and pink), (purple and white),
(pale lavender), (purple), (white)
Round-Lobed Hepatica; H. acutiloba (2), (3), (4), (5) Sharp-Lobed Hepatica; Hydrastis
(closeup), (2), (fruit),
(closer) Goldenseal; Isopyrum
biternatum False Rue Anemone; R. abortivus Littleleaf Buttercup; Ranunculus
fascicularis Early Buttercup; R. ficaria Lesser Celandine; Thalictrum clavatum Mountain Meadow Rue; T.
dioicum (female), (close), (male inflorescence)
Early Meadow Rue; T. pubescens, (flower closeup)
Tall Meadow Rue; Trautvetteria caroliniensis (2), (3) Tassel-rue; Trollius
laxus, (flower), (ssp. albiflorus)
thalictroides (habit 1), (habit 2),
(flower closeup), (yellow form), (2), (3) Blue Cohosh; Diphyllea cymosa (inflorescence), (2), (flower), (2), (in fruit), (2) Umbrella Leaf; Jeffersonia
diphylla (habit in flower), (flowers), (flower closeup), (habit),
(fruit) Twinleaf; Podophyllum peltatum (flower closeup)
Mayapple; Vancouveria hexandra White Inside-out Flower
canadense (male), (male closeup),
closeup), (fruits) Moonseed
Proteales is an order with an odd assortment of plants that have sometimes been misplaced in other groups. Proteaceae are showy, usually shrubby plants predominently found in the southern hemisphere, Platanaceae are wind-pollinated trees (Sycamore) of the northern hemisphere, whereas Nelumbonaceae (Water Lotus) are aquatic and superficially similar to Waterlilies (Nymphaeaceae), a group to which they were historically thought to be related. However, all Proteales, including Water Lotuses have tricolpate pollen, clearly indicating they are eudicots, and DNA evidence strongly supports them as each others' relatives despite their morphological dissimilarity.
Nelumbonaceae: Nelumbo lutea, (habit), (fruit)
American Water Lotus, Nelumbo hybrid Hybrid Water Lotus
Platanaceae: Platanus occidentalis (branch with male and female inflorescences), (female inflorescence),
(male inflorescence), (male
inflorescence dehiscing wind-borne pollen) American Sycamore
Proteaceae: Embothrium coccineum Chilean Firebush
Buxaceae: Pachysandra procumbens (inflorescence) Allegheny Spurge