Streptocarpus bampsii Eb.Fisch. & I.Darbysh., 2021

Fischer, Eberhard & Darbyshire, Iain, 2021, Five new species of Streptocarpus (Gesneriaceae) from Katanga, D. R. Congo, Plant Ecology and Evolution 154 (2), pp. 264-280 : 268-270

Streptocarpus bampsii Eb.Fisch. & I.Darbysh. , sp. nov.

( figs 3–4 , 9A ) –

Type: D.R. CONGO – Haut Katanga • Zone Lubudi, Kayo , Chutes de la Kalule Nord , forêt galerie au pied de la chute; 9°52′S, 26°03′E; 1250 m; 29 Jan. 1986; Bamps & Malaisse 8389; holotype: BR[BR0000016803367 , BR0000016803374 ].

Diagnosis – The species differs from Streptocarpus solenanthus in the straight and usually shorter corolla tube and the shorter lower lip of the corolla, the darker colouring of the corolla lobes and the longer calyx lobes. The species differs from Streptocarpus michelmorei in the smaller pale lilac corolla lacking a deep violet patch on the palate and behind, the corolla tube being almost straight and not deepened on the lower side at the middle, and the upper and the lower lip being almost equal while in S. michelmorei the lower lip is distinctly larger. It also differs from S. michelmorei in the distinctly shorter capsule.

Description – Monocarpic acaulescent herb. Unifoliate, lamina broadly ovate to nearly orbicular, 15–32 × 14–25 cm, base shallowly cordate, margin crenate-dentate, apex obtuse, usually withered, pubescent on upper and lower surface, with 10–15 pairs of lateral nerves, petiolode not exceeding 1 cm long, pubescent. Inflorescences 1–3 per plant, arising from the petiolode, peduncle up to 9.5(–11) cm long, pubescent. Pedicels 6–20 mm long, eglandular pubescent, bracts linearlanceolate, up to 5 mm long. Calyx divided to base, lobes lanceolate, 5–7 mm long, hairs on calyx eglandular. Corolla pale violet, lobes darker violet, tube outside whitish-violet, mouth pale violet to whitish-violet, 22–29 mm long, densely eglandular-pubescent, glabrous within, tube straight, not or only slightly expanded towards mouth,18–23 mm long, 3–4 mm in diameter, 5(–6) mm towards mouth, limb bilabiate, upper lip of two rounded lobes, 3–5 × 3–4 mm, lower lip of 3 rounded lobes, 4–5 × 4–5 mm. Stamens inserted in upper third of corolla tube towards mouth, filaments 3–6 mm long, glabrous, anthers white, 2–2.3 mm long, staminodes inserted below stamens, 0.6–1 mm long. Ovary densely eglandularpubescent, ovary and style 21–22 mm long. Capsules 50–70 × 1.5–2 mm, eglandular-pubescent.

Distribution – Endemic to south-eastern D.R. Congo (Haut Katanga), only known from the type collection.

Habitat – Epiphyte in gallery forest at foot of waterfalls, 1250 m elevation.

Etymology – Named after Paul Bamps, who made major contributions to the knowledge of the flora of Central Africa, and who collected the type.

IUCN conservation assessment (preliminary) – Critically Endangered: CR B2ab(iii). Streptocarpus bampsii is only known from the type collection. The estimated AOO is 4 km 2 (assuming a 4 km 2 grid cell size). The habitat, a gallery forest, is under potential threat of logging. As there is only one locality known, and to emphasize the clear threats (logging of gallery forests) to the type locality, we prefer to assess it preliminarily as Critically Endangered: CR B2ab(iii).

Figures

Figure 3 – Streptocarpus bampsii. A. Habit. B–C. Flowers.D. Corolla, dissected, showing stamens and staminodes. E. Corolla, lateral view. F. Stamens. G. Staminode. H. Hairs on corolla. From Bamps & Malaisse 8389. Illustration by Eberhard Fischer.

Figure 4 – Streptocarpus bampsii. A–B. Details of inflorescence. Photographs taken by Paul Bamps (Bamps & Malaisse 8389). © Paul Bamps, all rights reserved.

Figure 9 – A. Distribution map of Streptocarpus malachiticola, S. bampsii, and S. salesianorum. B. Distribution map of S. schaijesii and S. malaissei. Map created using ArcMap 10.8 (https://www. arcgis.com). © Esri and its licensors, all rights reserved.