MALVACEAE

MALLOW FAMILY

Steven R. Hill, except as specified

Annual, perennial herb, shrubs, trees, generally stellate-hairy; juice sticky; inner bark tough, fibrous
Leaves alternate, simple, petioled; blade generally palmately veined or lobed, stipules present
Inflorescence often leafy; whorl or involucre of bractlets often subtending calyx
Flower generally bisexual, radial; calyx lobes 5, margins abutting in bud; petals 5, free (fused at base to filament tube, so falling together); stamens many, filaments fused into a tube surrounding style, tube fused in turn to petal bases; pistil 1, ovary superior, chambers generally 5 or more, style branches, stigmas generally 1 or 2 X as many as chambers
Fruit of 5–many disk- or wedge-shaped segments, loculicidal capsule, or berry
Genera in family: 100 genera, 2000 species: worldwide, especially warm regions; some cultivated (e.g., Abelmoschus , okra; Alcea ; Gossypium , cotton; Hibiscus , Malvaviscus )
Recent taxonomic note: Recently treated to include Sterculiaceae [Angiosperm phylogeny Group 1998 Ann Missouri Bot Gard 85:531–553; Alverson et al. 1999 Amer J Bot 86:1474–1486; Bayer et al. 1999 Bot J Linn Soc 129:267–303]
Mature fruit important for identification.

MALACOTHAMNUS

BUSH MALLOW

David M. Bates

Subshrubs, shrubs; hairs sparse to dense, stellate (stalked or sessile), simple, and glandular
Stem erect; branches sometimes spreading
Leaf: blade toothed, lobes 0 or 3–7
Inflorescence head-like to panicle-like, composed of axillary clusters (each a cyme) variously arrayed; clusters few–many-flowered, loose to dense, congested or well separated; bractlets subtending calyx 3
Flower: petals > calyx, generally pale pinkish purple or white (often purplish when dry); filament column included; stigmas head-like
Fruit disk-like; segments 7–14, 2–5 mm, separating, each dehiscing into 2 valves, unarmed, smooth, top hairy
Seed 1 per fruit segment
Species in genus: 11 species: CA, nw Mex
Etymology: (Greek: soft shrub)
Spp. represent major morphological variants; they are all interfertile and sometimes intergrade in areas of proximity. Variation between populations (especially in hairs, inflorescence, and flowers) is high and of ± complex pattern within most species

Native

M. davidsonii (B.L. Rob.) Greene

DAVIDSON'S BUSH MALLOW

Plant 30–50 dm; hairs dense, appearing granular, generally tawny
Stem: branches generally stout
Leaf: blade 5–11(20) cm, ± round, thick, wavy-margined; upper surface generally densely hairy; lobes 3–7, generally rounded, overlapping (sinuses closed)
Inflorescence spike- to ± panicle-like; clusters generally peduncled, congested to well separated; bractlets 1.5–4 mm, < 1 mm wide
Flower: many abortive; calyx 5–9 mm, densely hairy, ± angled in bud; lobes 3–5 mm, ± = tube, triangular to ovate, sometimes 2–4 joined when flower open
Chromosomes: 2n=34
Ecology: Slopes, washes
Elevation: 250–700 m.
Bioregional distribution: c Outer South Coast Ranges (s Monterey, nw San Luis Obispo cos.), South Coast (e San Fernando Valley, Los Angeles Co.).Intergrades with M. fasciculatus
Horticultural information: In cultivation.