Carex ludwigii (Hochst.) Luceno & Martin-Bravo, 2015

Márquez-Corro, José Ignacio, Maguilla, Enrique, Villaverde, Tamara, Martín-Bravo, Santiago & Luceño, Modesto, 2017, Two new species in Carex sect. Schoenoxiphium (Cyperaceae) from southern Africa, Phytotaxa 303 (1), pp. 34-46 : 44

Key to C. ludwigii species group (clade D) of Carex sect. Schoenoxiphium

1. Utricles (4.1)4.5–6.5(7) mm long, linear to lanceolate, more than 4 times as long as wide ............................................................ 2

1’. Utricles (2.2)2.5–5.3(5.4) mm long, elliptic to ovoid, less than 3 times as long as wide ................................................................ 3

2. Permanent style base on nutlet with a conspicuous constriction at its middle; leaves up to 9(10) mm wide; at least some partial inflorescences more or less erect ............................................................................................................................. C. kukkoneniana

2’. Permanent style base on nutlet absent or very short, not constricted at its middle; leaves up to 14.4 mm wide; partial inflorescences usually pendulous ........................................................................................................................................................ C. pseudorufa

3. Utricles (4.3)4.7–5.3(5.4) × 1.7–2 mm, straight ................................................................................................................ C. badilloi

3’. Utricles (2.2)2.5–3.7(4) × (0.8)1–1.5(1.7) mm, frequently curved .................................................................................................. 4

4. Culms (4)10–65(90) cm long, (0.6) 0.8–1.5 mm wide at its middle part; leaves (1)1.5–2.5(2.8) mm wide .................. C. parvirufa

4’. Culms (54) 69–111 cm long, 1.9–2.5 mm wide at its middle part; leaves (2.4)3.2–6(6.9) mm wide ............................... C. ludwigii