Clerodendrum frutectorum Moore (1919: 249)

Meerts, Pierre, 2023, The genus Clerodendrum (Lamiaceae) in the flora of Central Africa (D. R. Congo, Rwanda, Burundi), Phytotaxa 594 (1), pp. 1-42 : 17-18

11. Clerodendrum frutectorum Moore (1919: 249) ; Thomas (1936); Moldenke (1986c: 472); Verdcourt (1992:103); Lebrun & Stork (1997: 511); Fernandes (2005: 102); Coates Palgrave (2005: 989).

Type:— D.R. CONGO. Shiwele , 19 February 1908, Kässner 2473 (holotype: K000192844; iso-: BM000798645 , BM000798646 (fragm.), BR0000008971333!, E00043060, HBG513434 ) .

= Clerodendrum capitatum var. subdentatum De Wildeman (1903: 117 ; 1921: 166); Durand & Durand (1909: 438). Type:—D.R. CONGO. Haut-Katanga, Plateau des environs de Lukafu, February 1900, Verdick 409 (holotype: BR0000016597402!).

Perennial woody herb, or shrub, occasionally sarmentose, 2–3 m; rootstock thick, suckering. Stem simple to sparingly branching, up to 5 mm diam. under inflorescence, hollow, striate, with mixed indumentum of short, almost papilliform hairs and longer patent hairs, without persistent petiole bases. Leaves clustered near shoot apex; petiole: 2–9.5(–11.5) cm, indumentum like stem; lamina ovate, or broadly ovate to elliptic or broadly obovate, (6–)9–20 × (3–) 6–15 cm, base rounded to subcordate, somewhat asymmetric, apex rounded, or obtuse, or acute to shortly acuminate, discolorous, pubescent on both surfaces (hairs ca. 0.5 mm), more concentrated on lower surface of veins, 4–6 veins on either side, prominent on lower surface, margin undulate to repand, sometimes entire. Inflorescence at shoot tip, subsessile, subtended by 2 to 5 subsessile foliaceous bracts (2–7 cm long), a hemispheric to shortly ovoid head, 3–5 cm diam. (corollas excluded), bracts ovate to obovate up to 2 cm long, decreasing in length from base to tip, acuminate, pale whitish green, hispid, veins prominent; bracteoles narrowly ovate-elliptic, ca. 15 × 2 mm. Flower: pedicel ca. 2 mm, hispid; calyx 17–23 mm long, tube narrowly campanulate, 6–8 mm long, shortly hispid, lobes narrowly ovate-elliptic, acuminate, 4–5 mm broad, pale green to whitish-green, rarely purple-tinged, pubescent without, veins prominent; corolla: tube 100–130 mm, glandular-pubescent, lobes obovate-elliptic, 13–18 × ca. 7 mm, white, puberulent without to subglabrous; stamens protruding 30–35 mm, anther 3–4 mm long. Fruit ca. 10 mm long.

Distribution in Central Africa:—D.R. Congo, Burundi.

Distribution elsewhere:— Tanzania, Zambia, Zimbabwe.

Habitat:—Savannah, termite mounds in dry woodland, riparian forest, dry evergreen forest, ravine with Euphorbia dawei ; 850–1300 m.

Selection of representative specimens:—D.R. CONGO. Bas-Congo: Gillet s. n. (see note). Forestier central: Bambesa, 1 April 1934, Brédo 1048 (BR!) (see note). Bas-Katanga: Musongoi, June 1950, Desenfans 1485 (BR!). Lacs Edouard et Kivu: Plaine de la Ruzizi, Mont Kalambo, 24 February 1950, Germain 6275 (BR!). Haut-Katanga: 19 km NW Lubumbashi, 19 February 1982, Malaisse & Robbrecht 1819 (BR!); Lubumbashi, Kasapa, 24 January 1970, Lisowski 210 (BR!); Près d’Elisabethvile [Lubumbashi], March 1933, Quarré 3102 (BR!, WAG).— BURUNDI. Lacs Edouard et Kivu: Cibitoke, 7 March 1971, Reekmans 255 (BR!); Bujumbura, 25 February 1970, Lewalle 4484 (BR!, MO); Territ. Bubanza, vallée Katunguru , 5 April 1972, Lewalle 6653 (BR!).

Notes:—1. This species is the Zambezian counterpart of the Congolian C. poggei ; the differences between the two species are mostly quantitative ( C. poggei is larger). A good discriminant character is the indumentum of shoots and petioles, which comprises both long patent hairs and short papilliform hairs ( C. poggei : short hairs only). Ambiguous specimens occur near the contact zone of the two species (Lewalle 4585, Thiébaud 325).

2. This is the first record of this species for Burundi.

3. C. frutectorum has often been misidentified as C. capitatum or C. rotundifolium in collections.

4. Gillet s. n. (BR00000020442507), from Bas-Congo, ca. 800 km west of the nearest localities, is probably this species, but the specimen is sterile. Brédo 1048 , from a locality in the north of D.R. Congo, very distant form the main range, is a poor specimen, but the identification is almost certain.