Lantana L.

Scientific Description

Common name. Lantanas. Family Verbenaceae.

Habit and leaf form. Shrubs, or herbs (rarely); evergreen; bearing essential oils. Plants prickly (short recurved prickles covering stems). Leaves cauline. Young stems tetragonal. To 3 m high. Self supporting, or climbing; the climbers scrambling. Leptocaul. Leaves medium-sized; not fasciculate; opposite; ‘herbaceous’; not imbricate; petiolate; aromatic, or foetid; simple; epulvinate. Leaf blades entire; flat; ovate; pinnately veined; cross-venulate; attenuate at the base, or cuneate at the base, or oblique at the base. Mature leaf blades adaxially scabrous; abaxially scabrous, or pubescent (more or less). Leaves without stipules. Leaf blade margins dentate; flat. Leaves without a persistent basal meristem. Leaf anatomy. Hairs present. Stem anatomy. Secondary thickening developing from a conventional cambial ring.

Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite. Entomophilous.

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’. Inflorescence many-flowered. Flowers in corymbs, or in heads, or in spikes (cylindrical). The terminal inflorescence unit racemose. Inflorescences axillary; dense corymbs or cylindric spikes, these usually axillary, pedunculate; pseudanthial, or not pseudanthial. Flowers subsessile, or sessile; bracteate; small; very irregular; zygomorphic. The floral asymmetry involving the perianth and involving the androecium. Flowers 4–5 merous; cyclic; tetracyclic. Free hypanthium absent. Hypogynous disk present, or absent. Perianth with distinct calyx and corolla; 10; 2 -whorled; isomerous. Calyx present; 5; 1 -whorled; gamosepalous; entire to lobed; shallowly lobulate (or truncate). Calyx lobes markedly shorter than the tube. Calyx erect; open in bud; exceeded by the corolla; regular, or bilabiate; persistent. Corolla present; 5; 1 -whorled; gamopetalous; lobed; irregularly blunt-lobed. Corolla lobes markedly shorter than the tube. Corolla imbricate; hypocrateriform and tubular; weakly bilabiate; hairy abaxially; initially cream to yellow, or pink to purple, or orange to red (becoming); deciduous. Corolla members entire. Androecial members definite in number. Androecium 4. Androecial sequence not determinable. Androecial members adnate (to the corolla tube); markedly unequal; free of one another; 1 -whorled. Androecium exclusively of fertile stamens. Stamens 4. Staminal insertion near the base of the corolla tube. Stamens all inserted at the same level (more or less), or inserted at markedly different levels; remaining included; didynamous; all more or less similar in shape; reduced in number relative to the adjacent perianth; fertile stamens representing the posterior-lateral pair and the anterior-lateral pair; oppositisepalous. Anthers separate from one another; dorsifixed; dehiscing via longitudinal slits; introrse; tetrasporangiate. Gynoecium 1 carpelled (ostensibly), or 2 carpelled (but the posterior member aborting). The pistil 2 celled (only the anterior pair of cells developing). Carpels reduced in number relative to the perianth. Gynoecium syncarpous; eu-syncarpous; superior. Ovary plurilocular; 2 locular. Locules secondarily divided by ‘false septa’. Gynoecium median. Ovary sessile. Ovary summit glabrous. Gynoecium stylate. Styles 1; simple; attenuate from the ovary; apical; not becoming exserted; hairless. Stigmas 1; 1 - lobed, or 2 - lobed. Placentation basal to axile. Ovules 1 per locule; ascending; non-arillate; anatropous.

Fruit and seed features. Fruit 4–6 mm long; fleshy; indehiscent; a drupe. The drupes with separable pyrenes (two). Fruit 2 celled; 2 seeded. Seeds non-endospermic. Cotyledons 2 (expanded, flat). Embryo straight.

Special features. The flowering nodes separated by extended internodes. Calyx limb 2 lobed, or 5 lobed. Corolla tube exceeding the calyx; slightly curved. The upper lip of the corolla incorporating 2 members, the lower 3; (posterior, adaxial) lip of the corolla entire to bilobed; upper (adaxial) lip of the corolla not concave. Lower (abaxial) lip of the corolla 3 lobed; not concave. The anterior pair of stamens exceeding the posterior pair.

Geography, cytology, number of species. Adventive. Not endemic to Australia. Australian states and territories: Western Australia, Northern Territory, Queensland, and New South Wales. A genus of ca 150 species; 1 species in Western Australia; 0 endemic to Western Australia.

Etymology. Said to be an ancient name for Viburnum, but this has not been verified.