Common Name: ACANTHUS FAMILY
Habit: [Annual, perennial herb to] shrub, [tree], nodes generally swollen. Leaf: simple, generally opposite, entire (toothed [lobed]); stipules 0. Inflorescence: variable, with bracts, generally also bractlets. Flower: bisexual; calyx deeply (3)4--5 lobed [(sepals free)]; corolla 4--5 lobed, radial to 2-lipped; stamens 2 or 4, epipetalous, anther sacs sometimes dissimilar in size or placement; ovary superior, 4--many-ovuled, chambers 1--2, placentas axile (free central), stigmas 1--2. Fruit: capsule, loculicidal, generally dehiscing explosively, valves 2. Seed: 1--4[+], each generally subtended by hook-like outgrowth that remains in fruit.
Genera In Family: 220 genera, 4000 species: especially tropics; some ornamental: Justicia (Beloperone, shrimp-plant), Acanthus, Thunbergia.
eFlora Treatment Author: Thomas F. Daniel, Margriet Wetherwax & Lawrence R. Heckard, except as noted
Scientific Editor: Thomas J. Rosatti.

Habit: Shrub [to tree]; roots spreading, exposed at low tide. Leaf: persistent, petioled; blade thick. Inflorescence: axillary, terminal, head-like, < peduncle; bractlets 3, generally < calyx, outer 1 > inner 2. Flower: calyx deeply 5-lobed; corolla 4-lobed, radial, rotate; stamens 4, attached at 1 level. Fruit: ellipsoid to ovoid, often asymmetric, 1-chambered, generally indehiscent; stalk not flat.
Etymology: (Avicenna, Persian physician, philosopher, 980--1037) Note: Placement in Acanthaceae s.l. fairly well established; sister group relationship with Thunbergioideae weakly supported (Schwarzbach & McDade 2002; Hilu et al. 2003).
eFlora Treatment Author: Thomas F. Daniel, Margriet Wetherwax & Dieter H. Wilken
Reference: Duke et al. 1998 Evolution 52:1612--1626
Unabridged Reference: Moran 1980 Madroño 27:143