Systematic Botany Exam II [GOERTEZ]

Gymnosperms

"Naked seed" plants — ovules NOT enclosed in an ovary at pollination; seeds in cones or singular with fleshy coat; 15 living families, ~800 species

Cycadaceae

Cycad family; shrub to tree with above-ground stems; large pinnate leaves with circinate leaflets; ovules borne along margin of megasporophylls (NOT true cones); motile sperm; 1 genus (Cycas)

Zamiaceae

Zamia family; underground stems (vs. above-ground in Cycadaceae); pinnate leaves; microsporophylls and megasporophylls in true cones; motile sperm; found in FL & GA

Ginkgoaceae

Ginkgo family; deciduous fan-shaped leaves with bifurcating venation; dioecious with X and Y chromosomes; wind pollinated but sperm motile; fleshy ill-smelling seed; 1 species only (Ginkgo biloba); "living fossil"

Taxaceae

Yew family; needles spreading in one plane (2-ranked), flattened; seeds solitary surrounded by fleshy aril (NOT a cone); Taxol cancer drug from Taxus bark; toxic to humans and animals

Cupressaceae

Cypress family; scale-like or awl-like leaves, opposite or whorled; small to medium woody cones (or berry-like in Juniperus); includes Sequoia (tallest tree) and Sequoiadendron (largest organism)

Pinaceae

Pine family; most important timber family; needle-like leaves; mostly woody pendent cones; 11 genera including Pinus, Abies, Picea, Tsuga

Picea

Spruce; 4-sided needles; sessile on woody pegs; rough branch texture; pendant cones

Abies

Fir; flat needles; sessile with round "suction cup" base; smooth branch texture; erect (upright) cones

Tsuga

Hemlock; flat needles with tiny petiole/woody base; rough branch texture; pendant cones

Pinus

Pine; needles in fascicles (bundles of 2–5); rough branch texture; pendant cones; only genus with fascicled needles

Pinus longaeva

Bristlecone Pine — oldest living organism at 5,000+ years

Sequoia sempervirens

Tallest living tree — ~380 ft ("Hyperion")

Sequoiadendron giganteum

Largest living organism — 3,000–3,500 years old

Gnetales

Gymnosperm group with angiosperm-like features: vessels in wood + a form of double fertilization; includes Ephedra, Gnetum, and Welwitschia

Welwitschia mirabilis

Only species in Welwitschiaceae; Namibia/Angola desert; only 2 strap-like leaves that persist for its entire life (up to 2,000 years)

Ephedra

Gnetales shrub/vine; tiny non-functional leaves; source of ephedrine; found in arid regions especially SW US

Nymphaeaceae

Water lily family; perennial aquatic herbs with large rhizomes; large floating/submerged leaves; solitary flowers; tepals 4–12; numerous stamens; berry or fleshy capsule fruit; examples: Nymphaea, Nuphar

Magnoliaceae

Magnolia family; trees or shrubs; alternate simple entire leaves with large deciduous stipules leaving scars; solitary terminal flowers; tepals 6 to numerous; numerous stamens; elongate receptacle; monosulcate pollen; aggregate of follicles (Magnolia) or samaras (Liriodendron)

Liliaceae

Lily family; herbs with bulbs and contractile roots; parallel venation; 6 distinct petaloid tepals often spotted; 6 extrorse stamens; monosulcate pollen; 3 connate carpels; superior ovary; loculicidal capsule; flat disc-shaped seeds with non-black seed coat

Malvaceae

Mallow family; stellate pubescence; mucilaginous sap; palmate venation; epicalyx (involucel); stamens fused into monodelphous staminal column (key feature!); loculicidal capsule or schizocarp; includes cotton (Gossypium), okra, chocolate (Theobroma cacao)

Apiaceae

Carrot family; aromatic herbs with hollow internodes and ribbed stems; compound umbel inflorescence (diagnostic!); inferior ovary; stylopodium; schizocarp of 2 mericarps with 5 ridges connected to carpophore; includes carrot, dill, parsley, celery; poison hemlock (Conium) is deadly

Arecaceae

Palm family; monoecious or dioecious trees/shrubs; diffuse secondary growth; large pinnate or palmate leaves in terminal rosettes; no root hairs (rely on mycorrhizae); 3 sepals + 3 petals; usually 6 stamens; fleshy/fibrous drupe; 1 seed with copious endosperm; includes coconut, dates, palm oil

Asteraceae

Sunflower/Composite family; capitulum (head) inflorescence with phyllaries; disk flowers (tubular, actinomorphic, central) and/or ray flowers (strap-like ligule, marginal); synantherous stamens; pappus (modified calyx); cypsela fruit; includes sunflower, dandelion, lettuce, artichoke

Capitulum

Compact head of sessile flowers on a common receptacle — diagnostic inflorescence of Asteraceae; flowers open from outside inward

Disk flower

Actinomorphic, tubular 5-toothed corolla; perfect or staminate; located in center of Asteraceae head

Ray flower

Zygomorphic, strap-like ligule (3–5 lips); sterile or pistillate; located at margin of Asteraceae head

Cypsela

Achene-like fruit of Asteraceae that includes tissue from the inferior ovary plus outer floral whorls; pappus often aids dispersal

Brassicaceae

Mustard family; glucosinolates (mustard oils) in myrosin cells; often T-shaped hairs; 4 sepals; 4 petals in cruciform arrangement; 6 tetradynamous stamens (2 short + 4 long); silique or silicle fruit with replum; includes broccoli, cabbage, radish, mustard, canola, Arabidopsis

Silique

Elongated Brassicaceae fruit more than 3× longer than wide; carpels split from persistent replum

Silicle

Short, wide Brassicaceae fruit less than 3× as long as wide

Tetradynamous

Having 6 stamens: 2 short outer + 4 long inner — diagnostic for Brassicaceae

Caryophyllaceae

Carnation/Pink family; herbaceous with swollen nodes; opposite leaves connected across node by transverse line (basally connate — key feature!); free central placentation; petals often notched ("pinked"); unilocular capsule; includes Dianthus, Gypsophila, Stellaria

Ericaceae

Heath family; strongly mycorrhizal shrubs on acid soil; urn-shaped sympetalous corolla; anthers poricidal with paired spurs; 8–10 stamens; includes blueberries, cranberries, rhododendrons, azaleas

Fabaceae

Legume/Pea family; root nodules with nitrogen-fixing bacteria; alternate stipulate often compound leaves with pulvinus; 5 sepals, 5 petals, 1 carpel, usually 10 stamens; legume fruit (pod splitting down BOTH suture AND midrib) — diagnostic!; second most economically important family

Legume

Dry, dehiscent fruit splitting down BOTH the suture AND the midrib — diagnostic fruit of Fabaceae

Mimosoideae

Fabaceae subfamily; trees/shrubs; bipinnate leaves; dense heads open simultaneously; radial non-showy corolla (valvate); showy colored filaments; examples: Acacia, Albizia, Mimosa

Caesalpinioideae

Fabaceae subfamily; trees/shrubs; once pinnate to bipinnate leaves; lax racemes open sequentially; bilateral corolla with banner INSIDE wings; examples: Cassia, Cercis, Gleditsia, Senna

Faboideae

Fabaceae subfamily; mostly herbs/shrubs; pinnate or trifoliate leaves; papilionaceous corolla with banner OUTSIDE wings; mono- or diadelphous stamens (9+1); examples: Pisum, Trifolium, Lupinus, Robinia

Papilionaceous

"Butterfly-like" Faboideae flower: large banner (standard) on outside, 2 wings flanking, keel (2 fused petals) on inside

Geraniaceae

Geranium family; palmately lobed to pinnately compound leaves; 5 sepals often awn-tipped; schizocarp with beak-like stylar column ("crane's bill") that recurves/twists at maturity to release seeds — diagnostic!; includes Geranium, Pelargonium, Erodium

Rosaceae

Rose family; mostly woody; alternate stipulate leaves with gland-tipped teeth; hypanthium (key feature); 5 sepals, 5 petals, numerous stamens; fruit varies by subfamily; includes apple, cherry, peach, raspberry, strawberry, rose

Rosoideae

Rosaceae subfamily; herbs/shrubs; pinnate or palmate compound leaves; superior ovary; aggregate of achenes or drupelets; examples: Rubus, Fragaria, Rosa, Potentilla

Spiraeoideae

Rosaceae subfamily; shrubs; simple leaves; superior ovary; aggregate of follicles or capsules; examples: Spiraea, Physocarpus

Amygdaloideae

Rosaceae subfamily (= Prunoideae); shrubs to trees; simple leaves; superior ovary; drupe fruit; example: Prunus (cherry, peach, plum, almond)

Maloideae

Rosaceae subfamily; shrubs to trees; simple leaves; INFERIOR ovary; pome fruit; examples: Malus (apple), Pyrus (pear), Crataegus

Solanaceae

Potato/Nightshade family; often toxic alkaloids; bicollateral vascular bundles; alternate simple leaves; accrescent calyx; 5 sympetalous petals (rotate, plicate corolla); 5 stamens with connivent anthers opening by pores or slits; berry or capsule; includes potato, tomato, pepper, tobacco, Datura, belladonna

Lamiaceae

Mint family; aromatic herbs/shrubs; square stems; opposite leaves with glandular trichomes; bilabiate sympetalous corolla (2-lipped); didynamous stamens; gynobasic style; 4-lobed ovary; 4 nutlets; includes basil, oregano, sage, rosemary, lavender, mint, thyme, teak

Oleaceae

Olive family; trees/shrubs; opposite simple to pinnate leaves; only 2 stamens — key feature!; 4 connate sepals and petals; capsule, samara, berry, or drupe; includes olive, ash (Fraxinus), forsythia, jasmine, lilac

Poaceae

Grass family; most economically important plant family; hollow round stems (culms); fibrous root system; includes wheat, rice, corn, barley, sorghum, sugarcane, bamboo

Hypanthium

Cup-like structure formed by fusion of bases of sepals, petals, and stamens — key feature of Rosaceae; ranges from flat to deeply cylindrical

Achene

Small, dry, indehiscent, 1-seeded fruit with thin pericarp not fused to seed (e.g., sunflower "seed")

Aggregate fruit

Fruit from a single flower with multiple separate carpels (e.g., raspberry — aggregate of drupelets)

Aril

Fleshy seed covering derived from the funiculus (seed stalk); e.g., in Taxaceae

Auriculate

Having ear-like lobes at the base of a leaf that clasp the stem

Bilabiate

Two-lipped; corolla divided into an upper and lower lip (e.g., Lamiaceae)

Bipinnate

Twice-pinnately compound; leaflets themselves divided (e.g., Mimosoideae)

Carpophore

Y-shaped stalk to which mericarps remain attached in Apiaceae

Cauliflorous

Flowers/fruits borne directly on the trunk or major branches (e.g., Theobroma cacao)

Circinate

Coiled like a fiddlehead; unrolling from tip to base — characteristic of cycad leaflets

Cordate

Heart-shaped leaf base

Didynamous

Having 4 stamens in 2 pairs of unequal length — characteristic of Lamiaceae

Dioecious

Individual plants are either male or female (not both); e.g., Ginkgo

Drupe

Fleshy fruit with a hard inner stone (endocarp) surrounding the seed; e.g., peach, cherry, olive

Epicalyx

Extra whorl of bracts resembling a second calyx outside the true calyx — e.g., Malvaceae (also called involucel)

Epipetalous

Stamens adnate (fused) to the petals

Fascicle

Bundle; in Pinus, needles clustered in groups of 2–5

Follicle

Dry, dehiscent fruit from a single carpel that splits along ONE side only

Free central placentation

Ovules borne on a central column not connected to the ovary wall — characteristic of Caryophyllaceae

Funiculus

Stalk connecting ovule/seed to the placenta

Gynobasic style

Style that arises from the base of/between the ovary lobes rather than from the apex — characteristic of Lamiaceae

Gynophore

Stalk supporting the gynoecium (pistil stalk); found in Brassicaceae

Hastulate

Leaf blade with basal lobes pointing sideways (halberd-shaped)

Inferior ovary

Ovary located below the sepals/petals; floral parts appear to arise from top of ovary (epigyny)

Involucre

Whorl of bracts surrounding a flower cluster (head); especially in Asteraceae

Ligule

Strap-like petal of ray flowers in Asteraceae; also a membrane or fringe at the leaf-sheath junction in grasses

Loculicidal

Capsule that splits along the midrib (back) of each locule

Loment

Modified legume with constrictions between seeds, breaking into 1-seeded segments at maturity

Megasporophyll

Leaf-like structure bearing ovules (seeds) in gymnosperms

Mericarp

One section of a schizocarp (e.g., one of the 2 halves of a carrot family fruit)

Monodelphous

All filaments fused into a single tube — e.g., Malvaceae staminal column

Monoecious

Male and female flowers on the SAME plant but in separate flowers

Monosulcate

Pollen with a single groove/aperture — characteristic of magnoliids and monocots

Nutlet

Small, hard, 1-seeded, indehiscent fruit; Lamiaceae matures into 4 nutlets from 4 ovary lobes

Pappus

Modified calyx of Asteraceae; forms bristles, awns, or scales aiding seed dispersal

Peltate

Shield-shaped; petiole attached to center of blade rather than edge

Perigyny

Hypanthium is free from the ovary; superior ovary with a cup around it

Phyllary

One of the involucral bracts in Asteraceae

Plicate

Folded like a fan or accordion — e.g., Solanaceae corolla in bud

Poricidal anther

Anther that opens by pores (not slits) — e.g., Ericaceae, Solanaceae

Pulvinus

Swollen joint at the base of a petiole or leaflet; functions in leaf movement — characteristic of Fabaceae

Replum

Persistent central partition in Brassicaceae fruit from which the valves separate

Revolute

Leaf margins rolled downward/under toward the abaxial (lower) surface

Samara

Winged, indehiscent fruit — e.g., Liriodendron (Magnoliaceae), ash (Oleaceae)

Schizocarp

Dry fruit that splits into single-seeded segments (mericarps) at maturity — e.g., Apiaceae, Geraniaceae, Malvaceae

Sessile

Without a stalk; sitting directly on the stem

Stellate hair

Star-shaped, branched hair — diagnostic for Malvaceae

Stipule

Paired appendages at the base of the petiole; presence/absence important in plant ID

Stylopodium

Disk-like expansion at the base of the style in Apiaceae, surmounting the inferior ovary

Superior ovary

Ovary located above the point of attachment of petals/sepals (hypogyny)