Carex truncatigluma C.B. Clarke (1904: 315) . Type:— CHINA. Zhejiang, Ningpo [Ningbo], May 1891, E. Faber 1541 (holotype: K-000960799!).

= Carex dolichogyne T. Koyama (1956: 164) . syn. nov. Type:— CHINA. Hunan, Mt. Yolu-shan [Mt. Yuelu], 15 May 1912, S. Yamazaki 31 (holotype: TI!).

= Carex gracilispica Hayata (1921: 62) . Type:— CHINA. Taiwan, Hoozan, 9 Apr. 1916, B. Hayata s.n. (holotype: TI!).

Based on the specimen S. Yamazaki 31, collected from Mt. Yuelu of Changsha in Hunan, Koyama (1956: 315) described C. dolichogyne as a new species. He distinguished it from Carex formosensis H. Lév. & Vaniot (in Léveillé, 1905: 216, placed in Mitrata clade in Roalson et al. 2021) in having rather sparsely flowered pistillate spikes, and longer (ca. 4.5 mm) utricles. In the protologue, Koyama also considered that his new species was similar to C. ligata Boott (in Bentham, 1861: 402, placed in Truncatigluma clade in Roalson et al. 2021), but differed from it by its shorter staminate spikes (ca. 1.5 cm long) and longer utricles.

Compared with other species in sect. Lageniformes (Ohwi, 1936: 340) Nelmes (1951: 366), Carex dolichogyne has the nutlets with a distinct, 0.7–0.8 mm long, cylindric neck at the apex, which is consistent to those of C. truncatigluma (nutlet necks cylindric, 0.5–1 mm long) (Figure 3). Thus, we reduced C. dolichogyne to a synonym of C. truncatigluma .