Description

Key Characters:

Growth Form: Prostrate to ascending perennial herbs.

Stems: Stems up to several m long.

Roots:

Leaves: Leaves compound. Opposite. Blades oblong to elliptic, (1.5–)3–10 cm long; leaflets 5–10(11) pairs, 7–28 mm long, 2.5–12 mm wide. Apex apiculate or rounded. Surfaces moderately to densely sericeous to long-strigose. Margins entire. Petioles very short. Stipules subulate to falcate, 3–9 mm long, 1–4 mm wide.

Flowers: Flowers in peduncles densely antrorsely strigose and hirsute, the latter hair type with pustulate bases. Flowers bisexual (perfect), actinomorphic. Calyx of 5 sepals; sepals lanceolate, slightly unequal, 7–14 mm long, 2–5 mm wide, margins scarious. Corolla of 5 petals; petals lemon yellow to bright yellow, deltate–obovate, 11–26 mm long, 6–15 mm wide. Stamens 10, in 2 whorls of 5, the outer whorl opposite the sepals and adnate to them basally, usually slightly longer than inner whorl; filaments filiform or subulate, without appendages; anthers cordate to sagittate. Ovary superior, long–strigose.

Fruit: Fruit 8–15 mm in diameter; mericarps dorsally crested and tuberculate; bearing 2 stout hard spines 5–10 mm long; sometimes also with 2 smaller spines near base; rarely spine 1 or absent; the crests short–hirsute; the hairs with pustulate bases. Seeds oblong–ovoid; seed coat membranous; embryo straight; endosperm absent.

Ploidy: 2n = 12; 36*

Habitat: Occurring in coastal habitats.

Elevation Range: 0–50(–100) m.