Notes on Carex (Cyperaceae) from China (IX): three new species of section Mitratae s.l.

Carex sect. Mitratae s.l. was established by Kükenthal in 1909 and can be distinguished from the closely related sections in having nutlets frequently discoid-annulate at the apex and a persistent style base. Based on field surveys and specimen examination, three new species of sect. Mitratae are described and illustrated here. Carex fatsuaniana was collected from Yunnan and differs from C. truncatigluma in having the utricles nearly glabrous, the nutlets with a ca. 0.5 mm long beak at the apex, the staminate spikes cylindrical, 5–7.5 cm long, 4–5 mm wide, and the pistillate glumes acuminate at the apex. Carex damingshanica was collected from Guangxi and differs from C. breviscapa and C. rhynchachaenium in having 3 or 4 spikes, the lateral spikes cylindrical, the pistillate glumes, utricles and nutlets all shorter than in the other two species. Carex radicalispicula was collected from Sichuan and differs from C. truncatirostris in having the staminate spikes clavate, 1.5–2 mm wide, the pistillate glumes pale yellow-white, 3–3.2 mm long, acuminate or short-awned at the apex, and the nutlets with 3 angles shallowly constricted at the middle