Thesium goetzeanum Engl.

Flora Zambesiaca. Vol. 9, Part 3. Polygonaceae-Myriaceae. Pope GV, Polhill RM, Martins ES. 2006.

Type

Type from Tanzania.

Morphology Reproductive morphology Flowers Gynoecium Style

Style 0.6–1.1 mm long; stigma reaching nearly to top of anthers

Ecology

Grassland and open grassy woodland on a variety of soils including serpentine; c. 770–2350 m.

Note

Thesium goetzeanum is characterized by its flowers, usually solitary in the axil of each bract, c. 7–13 racemosely arranged, relatively broad lanceolate bracts often with minutely scabridulous margins, usually adnate to the pedicel right up to the bracteoles (often adnate only halfway up the peduncle when 3-flowered cymules occur), perianth lobes with apical beard, and pale fruits with strongly raised ribs but less strongly raised reticulations. The plants often dry a peculiar shade of mauvish-grey, but can also dry greenish or fuscous. Variable in aspect: stems short and sparingly branched when regenerating after fire, taller and fastigiately branched when unburnt. Probably more or less glaucous in life, often drying a peculiar shade of mauvish-grey (as does its ally T. brevibarbatum). N.E. Brown (loc. cit. 460) suggested that the type of T. rogersii came, not from Victoria Falls as stated by the collector, but from the Transvaal; however, I see no reason to concur as the species is clearly common and widespread in Zimbabwe. Hill, when describing T. rogersii, diagnosed it against T. gracile, from which it is amply distinct. The type of T. rogersii differs from that of T. goetzeanum in the length of the bracts (which character, as well as overall height of the plants, was used by N.E. Brown (loc. cit. 456–458) in his key). However, length of bracts is variable over the whole range of the species and there is nothing else to distinguish them.

Distribution

Malawi Zimbabwe ZAM B, ZAM C, ZAM E, ZIM N, ZIM W, ZIM C, ZIM E, MAL N, MOZ M, MOZ S Zambia Mozambique Also in Tanzania, Rwanda and South Africa (former Transvaal, KwaZulu-Natal).

Morphology General Habit

Perennial herb with thick woody caudex; stems tufted from crown, 110–300(600) mm tall, sparingly to well branched, strongly ribbed by raised vascular strands terminating in midribs of leaves and bracts, leafy. Perennial herb with thick woody caudex; stems tufted from crown, 110–300(600) mm tall, sparingly to well branched, strongly ribbed by raised vascular strands terminating in midribs of leaves and bracts, leafy

Morphology Leaves

Leaves ascending to somewhat spreading and then slightly recurved, 6–20(30) × 1–1.5(1.7) mm midway on stem, smaller upwards and passing into bracts, often shorter and slightly broader at base, linear-lanceolate, apex apiculate, base broad, margins pale, cartilaginous, very minutely scabridulous or smooth, thick-textured, midrib raised on both surfaces. Leaves ascending to somewhat spreading and then slightly recurved, 6–20(30) × 1–1.5(1.7) mm midway on stem, smaller upwards and passing into bracts, often shorter and slightly broader at base, linear-lanceolate, apex apiculate, base broad, margins pale, cartilaginous, very minutely scabridulous or smooth, thick-textured, midrib raised on both surfaces

Morphology Reproductive morphology Flowers

Flowers 7–13 racemosely arranged at tips of branches, laxly panicled, usually solitary in each bract axil, occasionally paired or in 3-flowered cymules, sometimes all solitary except for 3-flowered terminal cymule. Flowers 7–13 racemosely arranged at tips of branches, laxly panicled, usually solitary in each bract axil, occasionally paired or in 3-flowered cymules, sometimes all solitary except for 3-flowered terminal cymule

Morphology Reproductive morphology Inflorescences Bracts

Bracts 4–12(20) × 1–2 mm, lanceolate, leaf-like, usually adnate to entire length of pedicel, rarely only to lower half of peduncle; bracteoles 2, 2–7.5 × 0.4–1.3 mm. Bracts 4–12(20) × 1–2 mm, lanceolate, leaf-like, usually adnate to entire length of pedicel, rarely only to lower half of peduncle; bracteoles 2, 2–7.5 × 0.4–1.3 mm

Morphology Reproductive morphology Flowers Pedicel

Pedicels (lowermost) 0.5–2(4) mm long; peduncles of cymules up to c. 10 mm. Pedicels (lowermost) 0.5–2(4) mm long; peduncles of cymules up to c. 10 mm

Morphology Reproductive morphology Flowers Perianth

Perianth greenish; tube 0.7–1.2 mm long, external glands conspicuous, elliptic, equalling tube; lobes 1.2–2 × 0.6–0.9 mm, triangular, subacute, densely white-bearded from apex. Perianth greenish; tube 0.7–1.2 mm long, external glands conspicuous, elliptic, equalling tube; lobes 1.2–2 × 0.6–0.9 mm, triangular, subacute, densely white-bearded from apex

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens inserted at base of lobes; filaments 0.2–0.5 mm long, almost hidden by anthers; anthers 0.4–0.8 mm long. Stamens inserted at base of lobes; filaments 0.2–0.5 mm long, almost hidden by anthers; anthers 0.4–0.8 mm long

Morphology Reproductive morphology Flowers Gynoecium Pistil

Style 0.6–1.1 mm long; stigma reaching nearly to top of anthers.

Morphology Reproductive morphology Fruits

Fruit c. 3–3.5 × 2.5–3 mm, yellowish- or slightly reddish-buff, ribs strongly raised, reticulations rather weakly raised in comparison. Fruit c. 3–3.5 × 2.5–3 mm, yellowish- or slightly reddish-buff, ribs strongly raised, reticulations rather weakly raised in comparison.