Asplenium pifongiae L.Y.Kuo, F.W.Li & Y.H.Chang

Chen, Cheng-Wei, Hsu, Tian-Chuan, Chao, Yi-Shan, Lu, Ping-Fong, Li, Chia-Wei, Tram, Nguyen Khanh Trinh, Nguyen, Ich Le Phuoc Thanh, Dang, Minh Tri, Luu, Hong Truong & Parris, Barbara, 2020, A newly recorded genus and twelve newly recorded species of ferns for Vietnam from Lang Biang Plateau, Phytotaxa 443 (2), pp. 121-143 : 123

Asplenium pifongiae L.Y.Kuo, F.W.Li & Y.H.Chang ( Fig. 2 )

Type:— TAIWAN. Chiayi County, Alishan Township, Alishan Forest Recreation Area, 2200 m, 6 July 2012, P.- F. Lu 25833 (holotype: TAIF-502797!).

Voucher specimens examined:— VIETNAM. Lam Dong Province, Lac Duong District, D ạ Chais Commune, Bidoup - Nui Ba National Park , near Mt. Bidoup peak, 2237 m, 12.085° N, 108.661° E, 22 June 2018, C.- W. Chen Wade5089 ( SGN!, TAIF!) ; same locality and date, T.- C. Hsu 10785 ( SGN!, TAIF!) .

Additional specimens examined:— TAIWAN. Chiayi County, Alishan Township, Alishan Forest Recreation Area , 1 July 2015, L.- Y. Kuo 4196 (TAIF-465804!) ; same locality and date, Y.- H. Chang 20150701–011 (TAIF-465805!) ; Chiayi County, Alishan Township, Mienyueh , 2350 m, 13 July 2017, T.- C. Hsu 9405 (TAIF-509961!) .

Distribution:—Previously only known from Taiwan.

Ecology:—In Vietnam, this species has only been found in broad-leaved mossy forest. There it grows as a low epiphyte on tree trunks.

Note:—In Vietnam, Asplenium pifongiae is morphologically most similar to A. normale D.Don (1825: 7) , both species belong to A. normale complex sensu Chang et al. (2018) and they were found sympatrically along the Bidoup peak trail. However, A. pifongiae can be distinguished from A. normale by having only 1 (rarely 2) sorus that is close and parallel to the basiscopic side of pinnae (versus having> 4 sori on both acroscopic and basiscopic sides, and angular to pinnae margin). This species is rare in both Taiwan and Vietnam. In Taiwan, it was proposed as critically endangered (CR) ( Li et al. 2016), whereas in Vietnam, no more than 50 individuals were found along the trail during our investigation. In addition to the two species mentioned above, Chang et al. (2018) recently reported the third species of A. normale complex for northern Vietnam, named A. normaloides Yan Fen Chang & Schneider (2018: 583) . Morphologically, A. normaloides is most similar to A. normale but differs from it by having highly perforate perispore (versus no or less perforate perispore) and more sori on its pinnae (10–14 versus less than 10).

Figures

FIGURE 2. Asplenium pifongiae—A. Habit. B. Rhizome. C. Lower lamina. D. Adaxial fertile pinnae. E. Abaxial fertile pinnae. C.-W. Chen Wade5089.