APIACEAE

CARROT FAMILY

Lincoln Constance

Annual, biennial, perennial herb (rarely shrub, tree), often from taproot
Stem often ± scapose, generally ribbed, hollow
Leaves basal and generally some cauline, generally alternate; stipules generally 0; petiole base generally sheathing stem; blade generally much dissected, sometimes compound
Inflorescence: umbel or head, simple or compound, generally peduncled; bracts present (in involucres) or not; bractlets generally present (in involucels)
Flowers many, small, generally bisexual (or some staminate), generally radial (or outer bilateral); calyx 0 or lobes 5, small, atop ovary; petals 5, free, generally ovate or spoon-shaped, generally incurved at tips, generally ± ephemeral; stamens 5; pistil 1, ovary inferior, 2-chambered, generally with a ± conic, persistent projection or platform on top subtending 2 free styles
Fruit: 2 dry, 1-seeded halves that separate from each other but generally remain attached for some time to a central axis; ribs on each half 5, 2 marginal and 3 on back; oil tubes 1–several per interval between ribs
Genera in family: 300 genera, 3,000 species: ± worldwide, especially temp; many cultivated for food or spice (e.g., Carum, caraway; Daucus; Petroselinum); some highly toxic (e.g., Conium). Underground structures here called roots, but true nature remains problematic. Mature fruit generally critical in identification; shapes generally given in outline, followed by shape in X -section of 2 fruit halves together.

AMMOSELINUM

Annual, taprooted
Stem erect or generally loosely branched, glabrous or roughened
Leaf: petiole entirely sheathing; blade oblong to obovate, ternately or ternate-pinnately dissected, segments linear to spoon-shaped
Inflorescence: umbels compound, peduncled or some sessile, puberulent; bracts generally 0; bractlets several, narrow; rays, pedicels few, spreading or spreading-ascending, unequal
Flower: calyx lobes 0; petals ovate, white, tips obtuse, not narrowed, not incurved
Fruit oblong-ovate, compressed side-to-side; ribs subequal, prominent, conspicuously bristly to glabrous; oil tubes per rib-interval 1–3; fruit axis notched at tip
Seed: face flat to concave
Species in genus: 4 species: 3 North America, 1 South America
Etymology: (Greek: sand-parsley)

Native

A. giganteum J.M. Coult. & Rose

DESERT SAND-PARSLEY

Plant 1–2 dm
Leaf: petiole 3–8 mm; blade 1.5–2.5 cm, obovate, segments 4–13 mm, linear, glabrous or roughened
Inflorescence: peduncles 0–4 cm; rays 4–8, 0–2 cm; pedicels 1–10, 0–8 mm
Fruit 3–5 mm, oblong-ovate; ribs corky, sharply scabrous
Chromosomes: 2n=38
Ecology: Heavy soil under shrubs
Elevation: ± 400 m.
Bioregional distribution: Sonoran Desert (Hayfield Lake, Riverside Co., 1922)
Distribution outside California: Arizona, n Mexico
Flowering time: Mar–Apr
Possibly alien in CA.