Craterispermum species

De Block, Petra & Randriamboavonjy, Tianjanahary, 2015, Three new species of Craterispermum (Rubiaceae) from Madagascar, Phytotaxa 206 (1), pp. 79-89 : 80

Key to the three new Craterispermum species

1a. Leaf blades narrowly obovate, 3–7 x 0.8–2 cm, higher order venation obscure to invisible on both surfaces; peduncles 1–2 mm long; inflorescences usually 3-flowered.......................................................................................................................... C. puffianum

1b. Leaf blades elliptic or broadly elliptic, obovate or broadly obovate, 1.8–14 x 1–5.5 cm; higher order venation prominent on both surfaces; peduncles 2–30 mm long; inflorescences (3–)4–9-flowered or with numerous flowers ....................................................2

2a. Inflorescences compact, with (3–)4–9 flowers; inflorescence axes 0–1 mm long...................................................... C. motleyanum

2b. Inflorescences lax, with numerous flowers; lateral inflorescence axes 1–5 cm long, central inflorescence axis usually ca. 0.5 cm long, rarely up to 5 cm long ........................................................................................................................................... C. cervicorne