Glossostelma cabrae (De Wild.) Goyder

Apocynaceae (part 2), David Goyder, Timothy Harris, Siro Masinde, Ulrich Meve, Johan Venter. Flora of Tropical East Africa, 2012

Morphology General Habit

Erect herb to 50 cm

Morphology Leaves

Leaves with petiole (0–)1–5 mm long; lamina spreading or ascending, oblong, obovate-oblong or rarely linear, lowest leaves present at anthesis 1.5 × 0.2 cm, upper leaves 3.5–8(–20) × (0.4–)1.5–3.1 cm, apex obtuse, rounded or retuse, apiculate, tapering gradually at the base, glabrous or with short, sparse hairs beneath, midrib channelled on upper surface, lateral veins clearly visible but neither impressed nor raised, numerous, parallel to each other and at ± 90° to the midrib

Morphology Reproductive morphology Inflorescences

Umbels with 2–4 flowers.

Morphology Reproductive morphology Inflorescences Peduncles

Peduncles pubescent, 1–12 mm long, or absent.

Morphology Reproductive morphology Inflorescences Bracts

Bracts deciduous, filiform, 5–6 mm long.

Morphology Reproductive morphology Flowers Pedicel

Pedicels 18–25 mm long, pubescent on one side

Morphology Reproductive morphology Flowers Calyx

Calyx lobes triangular, 5–6 × 1–1.5 mm, acute

Morphology Reproductive morphology Flowers Corolla

Corolla green or cream with reddish brown markings within, campanulate, lobed to 2–3 mm from the base; lobes recurved, obovate, 23–26(–28) × 9–14(–20) mm, apex acute or obtuse, glabrous except on the margins

Morphology Reproductive morphology Flowers Corona

Corona lobes green, attached to the staminal column 3–6 mm above the base of the gynostegium, 9–11 mm long, 2 mm wide at the base, the lower half of the lobe somewhat compressed laterally, falcate, arched over the head of the column and narrowed into the base of the erect, dorsally flattened, slightly fleshy, spatulate upper half, the apex rounded or truncate, with one or occasionally two narrowly triangular downward pointing flaps up to 2 mm long on the ventral face

Morphology Reproductive morphology Flowers Androecium Stamens Anthers

Anther appendages broadly ovate, ± 1.5 × 2 mm; corpusculum ± 0.3 mm long; translator arms ± 0.5 mm long.

Morphology Reproductive morphology Flowers Pollinia

Pollinia falcateoblong, ± 1 × 0.25 mm

Morphology Reproductive morphology Fruits

Follicles not seen

Ecology

Deciduous (miombo) woodland or open grassland, 1200–1500 m. Flowering November to December

Distribution

Range: Congo-Kinshasa, Angola, Zambia and Mozambique Flora districts: T7

Goyder, D. J., Gilbert, M. G. & Venter, H. J. T. (2020). Apocynaceae (part 2). In: M. A. García (ed.), Flora Zambesiaca, Vol. 7(3). Royal Botanic Gardens, Kew.

Type

D.R. Congo, Valley of the Tawa, 3.x.1902, Cabra-Michel 52 (BR holotype).

Morphology General Habit

Erect herb to c.50 cm

Morphology Leaves

Leaves petiolate or sessile, petiole (0)1–5 mm long; lamina oblong, obovate-oblong or rarely linear, spreading or ascending, lowest leaves present at anthesis 1.5 × 0.2 cm, upper leaves 3.5–8(20) × (0.4)1.5–3.1 cm, apex obtuse, rounded or retuse, apiculate, tapering gradually at the base, glabrous or with short, sparse hairs beneath, midrib channelled on upper surface, lateral veins clearly visible but neither impressed nor raised, numerous, parallel to each other and at c.90° to the midrib

Morphology Reproductive morphology Inflorescences

Umbels with 2–4 flowers

Morphology Reproductive morphology Inflorescences Peduncles

Peduncles pubescent, 1–12 mm long, or absent; bracts deciduous, 5–6 mm long, filiform

Morphology Reproductive morphology Flowers Pedicel

Pedicels 18–25 mm long, pubescent on one side

Morphology Reproductive morphology Flowers Calyx

Calyx lobes 5–6 × 1–1.5 mm, triangular, acute

Morphology Reproductive morphology Flowers Corolla

Corolla campanulate, lobed to 2–3 mm from the base, green or cream with reddish brown markings within; lobes 23–26(28) × 9–14(20) mm, obovate, apex acute or obtuse, recurved, glabrous except on the margins

Morphology Reproductive morphology Flowers Corona

Corona lobes green, attached to the staminal column 3–6 mm above the base of the gynostegium, 9–11 mm long, 2 mm wide at the base, the lower half of the lobe somewhat compressed laterally, falcate, arched over the head of the column and narrowed into the base of the erect, dorsally flattened, slightly fleshy, spathulate upper half, the apex rounded or truncate, with one or occasionally two narrowly triangular downward pointing flaps up to 2 mm long on the ventral face

Morphology Reproductive morphology Flowers Androecium Stamens Anthers

Anther appendages c.1.5 × 2 mm, broadly ovate

Morphology Reproductive morphology Flowers Pollinarium

Corpusculum c.0.3 mm long; translator arms c.0.5 mm long; pollinia c.1 × 0.25 mm, falcate-oblong

Morphology Reproductive morphology Seeds

Follicles not seen.

Distribution

Zambia, Mozambique. Also known from Angola, D.R. Congo and Tanzania.

Ecology

Deciduous woodland (miombo) or open grassland; 1200–1500 m.

Recognition

As in Glossostelmaceciliae, the degree of inflation of the corona lobes of G. cabrae is variable although the lobes are always more slender than in G. ceciliae.