Diplazium yinchanianum Zi Y. Liu, H. J. Wei & Y. H. Yan, 2018

Liu, Zi-Yue, Wei, Hong-Jin, Shang, Hui, Wei, Ran, Wang, Ying, Liu, Bao-Dong & Yan, Yue- Hong, 2018, Diplazium yinchanianum (Athyriaceae): A New Fern from the Border between China and Vietnam, Phytotaxa 343 (2), pp. 139-148 : 143-144

Diplazium yinchanianum Zi Y. Liu, H. J. Wei & Y. H. Yan , sp. nov. Figs. 3 , 4 .

Type:— CHINA. Guangxi Zhuang Autonomous Region: Fangcheng County, Dongzhong Town , Shiwandashan mountains , 21° 39′ 05″ N, 107° 29′ 45″ E, alt. 580 m, 24 Apr. 2014, Y. H. Yan, H. J. Wei & Y. Wang 13341 (holotype CSH-0065059!; isotypes CSH-0065051!, CSH-0065052!, CSH-0065053!, CSH-0065054!, CSH-0065060!) .

Diplazium yinchanianum is morphologically most similar to D. yaoshanense in having slender creeping rhizomes, abrupt laminae apices, and linear sori, but differs from the latter in having oblong lamina that has an apical pinna similar to lateral pinnae (vs. deltoid-lanceolate lamina with pinnatifid apex distinct from lateral pinnae). The phylogenetic analysis showed that they are not conspecific. Instead, D. yinchanianum was resolved as closely related to D. virescens . However, D. virescens is distinctive as it has bipinnate-pinnatifid laminae, linear-lanceolate scales with toothed margins and the toothed scales appear to be different from the distally toothed scales of D. yaoshanense ( Fig. 5 ). Diplazium virescens has reniform or subreniform spores and the perispores are aculeate with massive folds, while D. yaoshanense has subreniform spores and the perispores are hyaline and widely rugate. In contrast, D. yinchanianum has subreniform spores and the perispores are broadly flake-like ( Fig. 6 ; Chang et al. 2001; He & Kato 2013). These species can be identified with the key provided below.

Figures

FIGURE 3. Diplazium yinchanianum.—A. Habit.—B. Portion of pinna (drawn by Hong-Jin Wei, based on the holotype).

FIGURE 4. Diplazium yinchanianum Zi Y. Liu, H. J. Wei & Y. H. Yan.—A. Habit.—B. Adaxial view of laminae.—C. Abaxial view of portion of lamina.—D. Apical pinna.—E. Rhizome with lower portions of stipes.

FIGURE 5. Morphological comparison of basal petiole scales of Diplazium yinchanianum (A), D. virescens (B), and D. yaoshanense (C).

FIGURE 6. Spore morphology. Diplazium yinchanianum (A, B); D. yaoshanense (C); D. virescens (D). D is from Chang et al. (2001).