Clerodendrum capitatum var. pubitubum Meerts, 2023

Meerts, Pierre, 2023, The genus Clerodendrum (Lamiaceae) in the flora of Central Africa (D. R. Congo, Rwanda, Burundi), Phytotaxa 594 (1), pp. 1-42 : 11

6c. Clerodendrum capitatum var. pubitubum Meerts , var. nov. — Fig. 2 .

Type:— D.R. CONGO. Bas-Katanga , Upemba, Kanonga, forêt katangaise sur terrain argilo-sablonneux, ± 675 m, 10 February 1949, Van Meel in de Witte 5368 (holotype: BR0000016591011!; iso-: WAG.1613183) .

Differs from the type variety by the calyx tube shortly pubescent and the margin of calyx lobes with shorter cilia (ca. 0.5 mm).

A shrub. Stem reddish with pale lenticels, mixed indumentum of short hairs (often retrorse) and long patent hairs; persistent petiole bases ca. 4 mm long. Leaf: petiole (0.5–)1.5–3.0 cm, pilose; lamina elliptic to obovate-elliptic, 6–13.5 × 2.5–8 cm, base cuneate, rounded or subcordate, apex acuminate, 4–5 veins on either side, upper surface strigulose, reticulum prominulent, lower surface shortly hispid on veins, reticulum most prominent, margin entire, ciliate. Inflorescence capitate, 25–35 mm in diam. (corolla excluded), subtended by subsessile uppermost leaves. Flower: bracts 13–15 × 3–4 mm, pubescent, ciliate like calyx; pedicel 1–2 mm, pubescent; calyx 13–18 mm, tube 2–3 mm long, shortly pubescent (hairs ca. 0.5 mm), lobes ovate, 10–13 × 4–6 mm, acuminate into a fine point, pale whitish-green, with a purplish tinge, reticulum prominent, sparsely pubescent, margin shortly ciliate (cilia 0.2–0.7 mm, pallid); corolla: tube 80–100 mm, with glandular hairs, lobes obovate, ca. 12 × 6 mm long, obovate, with glandular hairs on the outer surface, flower bud ca. 11 × 9 mm, stamens projecting ca. 30 mm beyond throat, anther ca. 2 mm long. Fruit: not observed.

Distribution in Central Africa:—D.R. Congo (Bas-Katanga and Haut-Katanga).

Distribution elsewhere:—Not known elsewhere; endemic of D.R. Congo.

Habitat:— Brachystegia woodland; 675–1700 m.

Specimens studied:— D.R. CONGO. Bas-Katanga: Kanonga , forêt katangaise sur terrain argilo-sablonneux, ± 675 m, 10 February 1949, Van Meel in de Witte 5368 (BR!, WAG) . Haut-Katanga, Lusinga , 29 March 1948, de Witte 03555 (BR!, P) .

Note:—The pattern of pubescence of the calyx is reminiscent of C. cephalanthum subsp. montanum ; however, in the latter, the calyx tube is not contracted above ovary, calyx lobes do not have prominent reticulum, and the corolla tube is shorter (<4 cm).

Figures

FIGURE 2. Clerodendrum capitatum var. pubitubum (Van Meel in de Witte 5368 (BR)). Fruiting calyx. Scale bar is 1 cm. Drawing by Pierre Meerts, Botanical Garden Meise (©).