Barleria holstii Lindau

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

Morphology General Habit

Perennial herb or subshrub, 50–200 cm tall, sometimes scrambling; stems sparsely to densely buff- or yellow-strigose, hair bases swollen with age and persisting on mature woody stems.

Morphology Leaves

Leaves elliptic, 6.5–15.5 × 2–5.5 cm, base long-attenuate or -cuneate, apex attenuate or acuminate, surfaces strigose, hairs most numerous on margin and veins beneath; lateral veins 5–6 pairs; petiole 0–6 mm long.

Morphology Reproductive morphology Inflorescences

Inflorescence axillary, contracted (1)2–8-flowered unilateral cymes to 2 cm long; bracteoles pale green or tinged purple, pairs unequal and offset, the larger ovate or elliptic, often asymmetric, 12–22 × (3)6–12 mm, the smaller proportionally narrower, more strongly asymmetric and declinate, each with denticulate margin, teeth narrow and an apical bristle.

Morphology Reproductive morphology Flowers Calyx

Calyx green, usually paler towards base and centre, with darker reticulate venation; anterior lobe ovate or elliptic, 12–20 × 7–13 mm, base obtuse or rounded, margin as bracteoles or subentire, apex emarginate or truncate, surface strigose; posterior lobe broadly ovate, 17–30 × 10–19 mm, base rounded, apex acute or subattenuate; lateral lobes lanceolate, 3.5–6 mm long.

Morphology Reproductive morphology Flowers Corolla

Corolla 30–43 mm long, white, pale-blue or pale-purple, pubescent externally with mixed eglandular and glandular hairs; tube 19–23 mm long, funnel-shaped above attachment point of stamens; limb in 4+1 arrangement; abaxial lobe 12–22 × 8–18 mm, offset by 3–5 mm; lateral and adaxial lobes 9–18 × 6–13 mm.

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens attached 7–10 mm from corolla tube base; filaments 18–29 mm long; anthers 2.5–3.2 mm long; lateral staminodes 1–3 mm long, pubescent, antherodes 0.5–0.9 mm long.

Morphology Reproductive morphology Flowers Gynoecium Ovary

Ovary glabrous; stigma linear, 1–2 mm long.

Morphology Reproductive morphology Fruits

Capsule 13.5–15 mm long, glabrous.

Morphology Reproductive morphology Seeds

Seeds 5.5–6 mm long and wide.

Distribution

Also in Tanzania.

Ecology

Mixed evergreen or semi-evergreen forest and degraded Albizia forest; in Tanzania also in lowland and riverine forest and thicket; 900–1300 m.

Conservation

Conservation notes: Rare in the Flora area but more frequent in lowlands of Tanzania; assessed as Near Threatened in F.T.E.A.

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation

Predicted extinction risk: not threatened. Confidence: confident