Grangea grangeoides (J.-P. Lebrun & Stork) Beentje, Henk & Lachenaud, Olivier, 2020

Beentje, Henk & Lachenaud, Olivier, 2020, The inclusion of Akeassia in Grangea (Asteraceae) and description of a new species from Gabon: Grangea ogoouensis, Candollea 75 (2), pp. 311-319 : 314

Grangea grangeoides (J.-P. Lebrun & Stork) Beentje & O. Lachenaud, comb. nov.

≡ Akeassia grangeoides J.-P. Lebrun & Stork in Candollea 48: 332. 1993.

Holotypus: CONGO REPUBLIC: Île M’Bamou-Sinoa, 13.II.1969, F. Hallé 1674 ( P [ P025765 ] image seen; iso-: ALF, K!).

Annual herb 3–15(–38) cm; stem sparsely pilose-scabrid. Leaves slightly obovate, (3–)8 – 50(– 90) × 3– 24(– 35) mm, base long-attenuate with very base half-clasping stem, margin dentate in upper 2/3 with teeth to 3 mm deep, apex acute; sparsely pilose to minutely hispid, more densely so on midrib, veins and sometimes the margin, occasionally also sparsely glandular between hairs. Inflorescence of 3–8 capitula in a tight shortly stalked group axillary to upper leaves and/ or terminal; capitula 1.8–3 mm high, 2–4.5 mm in diameter; stalks of individual capitula 1–1.5 mm long; phyllaries 24–28 in two rows, green when fresh, elliptic to slightly obovate, 1.2–1.5(–2) × 0.3–0.4 mm, the outer with multicellular hairs and sometimes pectinate. Florets 34–50, yellow to orange; outer florets female, in 2–4 rows, widest at base and ending in a very narrow minutely 3–4-toothed apex, 0.3–0.7 mm long; inner florets 20–28, bisexual, slightly infundibuliform, 0.8–1.2 mm long of which the four lobes 0.1– 0.2 mm, glandular and apparently without trichomes. Achenes of outer florets slightly obovoid, 0.5–0.8 mm long, glandular and sometimes minutely pilose, with 0–3(–5) sub-plumose or barbellate pappus bristles, rapidly caducous, 0.2– 0.4 mm long; achenes of inner florets 0.6–0.9 mm long, scattered-glandular, with 4–9(–12) flattened to almost cylindrical barbellate pappus bristles 0.3–0.7 mm long.

Distribution and ecology. – This species is widespread in West and Central Africa, occurring from Senegal to the Democratic Republic of Congo, and grows on river-banks just above water level; recorded altitudes are 50–480 m in Gabon, and down to sea level elsewhere.

Notes. – A line drawing of this species is available in LEBRUN & STORK (1993) and a colour photograph in VANDE WEGHE et al (2016: 755). LEBRUN & STORK (1993) cited three collections from Gabon, two of which (Fleury in Chevalier 26242 and Anton-Smith 278) actually belong to our new species G. ogoouensis . In their description, they mentioned capitula up to 4.5 mm high and 7 mm in diameter, and a pappus with up to 15 free bristles, characters which may refer to G. ogoouensis ; the abundant material of G. grangeoides that we have seen constantly shows smaller capitula and fewer pappus-bristles.