CONVOLVULACEAE

MORNING-GLORY FAMILY

Lauramay T. Dempster (except Calystegia)

Perennial (annual), generally twining or trailing
Leaves alternate
Inflorescence: cyme or flowers solitary in axils; pedicels often with 2 bracts
Flower bisexual, radial; sepals 5, ± free, overlapping, persistent, often unequal; corolla generally showy, generally bell-shaped, ± shallowly 5-lobed, generally pleated and twisted in bud; stamens 5, epipetalous; pistil 1, ovary superior, chambers generally 2, ovules generally 2 per chamber, styles 1–2
Fruit: generally capsule
Seeds 1–4(6)
Genera in family: 50 genera, 1,000 species: warm temp to tropical; some cultivated as ornamental
Recent taxonomic note: Recently treated to include Cuscutaceae [Angiosperm Phylogeny Group 1998 Ann Missouri Bot Gard 85:531–553].
(Family description, key to genera by L.T. Dempster)

CALYSTEGIA

MORNING-GLORY

Richard K. Brummitt

Perennial, subshrub from caudex or rhizome, glabrous to tomentose
Stem very short to high-climbing, generally twisting and twining
Leaf generally > 1 cm, linear to reniform, often sagittate to hastate, rarely deeply divided
Inflorescence: peduncle generally 1-flowered; bractlets small and remote from calyx to large and concealing calyx, sometimes lobed
Flower generally showy; corolla glabrous, white or yellow to pink or purple; ovary chamber 1 (septa generally incomplete), stigma lobes 2, generally swollen, cylindric or oblong, ± flattened
Fruit ± spheric, ± inflated
Seeds generally ± 4
Species in genus: ± 25 species: temp, worldwide
Etymology: (Greek: concealing calyx, from bractlets of some)
Reference: [Brummitt 1980 Kew Bull 35(2):327–328]
Intergradation common; intermediate forms often difficult to identify. Appears similar to Convolvulus , but anatomy suggests that the 2 genera are not very closely related.

Native

C. peirsonii (Abrams) Brummitt

PEIRSON'S MORNING-GLORY

Perennial from rhizome, glabrous, ± glaucous
Stem decumbent to weakly climbing, < 0.4 m
Leaf: blade < 2 cm at midrib, narrowly triangular; lobes sometimes = blade, broadest at tip, generally distinctly 2-tipped; sinus rounded to ± square
Inflorescence: peduncle 2–8 cm, generally < subtending leaf; bractlets attached 0–3 mm below calyx and overlapping it, 3–7 mm, 2.5–4 mm wide, elliptic to widely oblong, entire, flat
Flower: calyx 9–13 mm; corolla 25–40 mm, white
Ecology: UNCOMMON. Rocky slopes
Elevation: 1000–1500 m.
Bioregional distribution: n San Gabriel Mountains, adjacent Mojave Desert (Antelope Valley)
Flowering time: May–Jun
Synonyms: Convolvulus p. Abrams
Intergrades with C. longipes , mainland coastal C. macrostegia, C. occidentalis subsp. o., perhaps C. sepium
Horticultural information: TRY.