Description :

• Shrublets, suffrutices or perennial herbs, rarely annual, mostly glandular, sometimes aromatic or foetid; stems leafy throughout
• Leaves usually opposite, sometimes alternate upwards, variously shaped, bases either ± connate or decurrent in narrow wings or ridges, entire to toothed, rarely more deeply lobed
• Flowers mostly solitary in axils of leaves or bracts, in ± racemose inflorescences, sometimes in cymules or cymose racemes, sometimes panicled
• Bracts at most adnate to extreme base of pedicel
• Calyx bilabiate, sometimes obscurely so; posterior lip 3-lobed, anterior lip 2-lobed, or rarely regularly divided into 6-9 lobes; lobes ± linear-lanceolate, usually pubescent
• Corolla tubular, nearly regular, 5-lobed; tube usually funnel-shaped, rarely cylindrical, mouth round; lobes spreading, suborbicular to oblong, entire, usually glandular-pubescent outside, often with glistening glands as well, inside usually with 1-5 longitudinal bands of clavate hairs in throat, or glabrous, rarely with clavate hairs extending from throat out on to lower part of lobes; posterior lobes exterior in bud
• Stamens 4(5), didynamous; filaments usually arising in upper part of corolla tube, not decurrent, in 2 species arising in lower part of tube and then all included; posterior pair either included or exserted, anterior pair exserted; anthers synthecate, dorsifixed
• Nectary semi-annular
• Ovary bilocular, ± elliptical, often with glistening glands at least on sutures, rarely glandular-pubescent as well; ovules many per locule; style filiform; stigma usually lingulate with 2 marginal bands of stigmatic papillae (rarely short and minutely bifid), exserted, in 2 species shortly bifid (not papillose), deeply included
• Fruit a septicidal capsule with a short loculicidal split at tip of each valve, glabrous or with glistening glands
• Seeds roughly elliptical, sometimes angled by pressure, amber-coloured, pallid or grey- to violet-blue; testa thin, tightly investing alveolate endosperm, with several longitudinal rows of transversely elongated pits in a chequer-board pattern

Nomenclature:

• Sutera Roth
  • Roth: 172 (1807; not of 1821)
  • Hiern: 243 (1904) in part
  • Hilliard: 220 (1994)
• Chaenostoma Benth.
  • Bentham: 374 (1836) name conserved
  • Greuter et al.: 298 (1994)
• Sphenandra Benth.
  • Bentham: 373 (1836)
• Palmstruckia Retz.
  • Retzius: 15 (1810) name rejected

Distribution & Notes:

• Global : Species 49, Africa south of the Cunene and Zambezi Rivers
• Southern Africa : Species 47, widespread but especially in Western and Eastern Cape