Pyrrosia annamensis (Christ) Li Bing Zhang, X.M.Zhou & C.W.Chen, 2017

Zhou, Xin-Mao, Chen, Cheng-Wei & Zhang, Li-Bing, 2017, Pyrrosia annamensis comb. nov. (Polypodiaceae) from Southeast Asia and lectotypification of Cyclophorus rhomboidalis, Phytotaxa 309 (1), pp. 90-94 : 90

Pyrrosia annamensis (Christ) Li Bing Zhang, X.M.Zhou & C.W.Chen , comb. nov. ( Fig. 1 )

Basionym:— Niphobolus annamensis Christ (1905: 74) .

Type:— VIETNAM. Quang Binh: 1904, P. Cadière 38 (holotype P-00626554!, isotype BM-001038335!).

Taxonomic notes:— Pyrrosia annamensis has been widely treated as a synonym of P. flocculosa (D. Don 1825: 1) Ching (1935: 66) with the type (BM-001038337!; Fig. 2 ) from Nepal ( Hovenkamp 1986), but the former has undulate and revolute lamina margins (vs. usually slightly lyrate lamina margins in P. flocculosa ). It also differs sometimes by having slightly dimorphic fronds where some fronds have an acuminate apex and laminae that are widest in the middle, and other fronds with obtuse to subrounded apices and laminae that are widest near the apex (vs. strictly monomorphic fronds with acuminate apices and laminae that are often widest toward the base in P. flocculosa ). In addition, the former has lamina bases nearly symmetrical and cuneate (vs. lamina bases usually strongly asymmetrical and truncate on one side in P. flocculosa ). Furthermore, P. annamensis has laminae 1.3–2(–3) cm wide (vs. 3–5(–8) cm wide in P. flocculosa ). Our molecular data ( Zhou et al. 2017) resolved these two species in very different clades, suggesting that they are different species despite their apparent similarity.

As far as we know, Pyrrosia annamensis is only distributed in Laos, Vietnam, and southern China (Guangxi and Yunnan).

Another related name is Cyclophorus rhomboidalis Bonaparte (1918: 126 & 191) [≡ Pyrrosia mollis f. rhomboidalis (Bonaparte) Christensen & Tardieu-Blot (1939: 206) ; P. rhomboidalis (Bonaparte) Ching (1935: 72) ], which has also been treated as a synonym of P. flocculosa by Hovenkamp (1986). It may in fact be synonymous with P. annamensis , however, further study is needed. The type of C. rhomboidalis was collected from southern Vietnam [ VIETNAM. Phan Rang [Ninh Thuan] Province, Lang-Bian Mountains, Aug. 1910, P. A. Eberhardt 119 [lectotype, P-00626552!; here designated!; Fig. 3 ). Remaining syntypes: Same locality, 1910, P. A. Eberhardt 106 (BM-001038334!, P-00626553!)].

Figures

FIGURE 1. Holotype of Pyrrosia annamensis (P-00626554).

FIGURE 2. Holotype of Pyrrosia flocculosa (BM-001038337).

FIGURE 3. Lectotype of Cyclophorus rhomboidalis (P-00626552).