Brachystephanus Nees

Flora Zambesiaca Acanthaceae (part 2) by Iain Darbyshire, Kaj Vollesen and Ensermu Kelbessa

Morphology General Habit

Perennial herbs or subshrubs, sometimes monocarpic and cyclically mass-flowering (plietesial).

Morphology Stem

Stems (sub-)4-angular, often sulcate between angles when young.

Morphology Leaves

Leaves evergreen or rarely deciduous, opposite-decussate, pairs equal to anisophyllous, blade margin crenulate to subentire; lower leaves petiolate, uppermost leaves often reduced and subsessile; cystoliths numerous, ± conspicuous.

Morphology Reproductive morphology Inflorescences

Inflorescences terminal and sometimes also in upper leaf axils; spiciform or paniculate thyrses, cymule branching dichasial or partially monochasial, or cymules reduced to a single flower; bract pairs equal, free; bracteoles paired, as bracts or much-reduced.

Morphology Reproductive morphology Flowers Calyx

Calyx tubular, divided almost to base into 5 linear(-lanceolate) lobes, subequal to unequal in length.

Morphology Reproductive morphology Flowers Corolla

Corolla bilabiate; tube cylindric to campanulate, long to very short; upper lip either subulate or more broadly ovate to elliptic, apex acute, obtuse, apiculate or emarginate; lower lip oblong to elliptic, apex minutely to conspicuously 3-lobed, rugula absent.

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens 2; filaments attached at or just below mouth of corolla tube, ± long-exserted, glabrous; anthers monothecous, basally muticous.

Morphology Reproductive morphology Flowers Androecium Staminodes

Staminodes absent.

Morphology Reproductive morphology Flowers Disc

Disk annular or shallowly cupuliform.

Morphology Reproductive morphology Flowers Gynoecium Ovary

Ovary oblong-ellipsoid, glabrous or largely so, bilocular, 2 ovules per locule; style filiform, ± long-exserted, glabrous; stigma either minutely clavate or conspicuously capitate, apex shallowly bilobed.

Morphology Reproductive morphology Fruits

Capsule stipitate, placental base inelastic.

Morphology Reproductive morphology Seeds

Seeds 4 per capsule, or 2 by abortion, held on retinacula, lenticular, tuberculate.

Distribution

A genus of 22 species distributed in tropical Africa and Madagascar.