English: Guyalone.
German: Geissoloma.
Clades: Geissolomataceae, Crossosomatales,Thymelaeales, Malvidae, Malvanae, Angiospermae, Plants
Region: Southern Africa, Western Cape.
Habitat: moist mountain fynbos slopes and damp peaty soils.
Content: accumulates aluminum; calcium oxalate crystals in druses.
Use: botanical, evolutionary, relict-species interest.

BotanyType: shrub; evergreen; non-succulent, xerophytic; low-growing, 50 to 125 cm tall.
Root: deep woody taproot; fibrous fine lateral roots.
Stem: young stems sharply 4-angled; possesses normal secondary growth with cork cambium present.
Leaves: decussate (opposite, in 4 distinct rows along stems); simple; leathery (coriaceous); ovate; sessile to subsessile; cordate base, acute apex; thickened margins; small subulate stipules on the short petiole base.
Inflorescence: solitary, on short lateral axillary branches.
Flowers: hermaphroditic (bisexual); actinomorphic; 4-merous; lacking true petals; possessing 4 persistent, petal-like pink tepals, turning carmine with age; subtended by 3 pairs of decussate, persistent bracts; 8 stamens (4 + 4); 4-carpellate superior ovary.
Pollination: by iinsects.
Fruit: capsule, dry, hard; 4-lobed; loculicidal;enclosed within the persistent perianth.
Seed: 1 oblong, smooth, whitish, per locule;reniform-shaped; with endosperm; straight central embryo.
Dispersion: mechanical, by rain splash or water flow.