Pteris omeiensis Ching

Yang, Dongmei, Wang, Jiamei, Guo, Rui, Zhu, Hongjuan, Ma, Changwang, Yu, Jing, Liu, Ya, Wu, Yougen & Shang, Hui, 2024, New taxonomic treatments in the Pteris fauriei group (Pteridaceae), Phytotaxa 647 (3), pp. 223-236 : 233-234

Pteris omeiensis Ching in Bull. Fan. Mem. Inst. Biol. new ser. 1: 312. 1949.

Type:— CHINA. Szechuan: Mt. Omei , C.S. Chang 755 (lectotype PE!), T.C. Lee 3209 (syntype PE!), Nos. 17899 , 17956 , 18018 ex Dept. Biol. Nat. Szechuan University (paratype SZ!)

Description: —Plants 50–80 cm tall. Rhizome short, thick, erect, sparsely scaly but apex with dense, linear-lanceolate brown scales. Fronds clustered; stipe hard, stout, 50–60 cm long, basally reddish brown, sparsely scaly, upper part and rachis and costae pale green; lamina 2(or 3)-pinnatipartite, narrowly oblong, 30–35 × 10–20 cm; lateral pinnae 8–12 pairs, 12–16 × 1.5–1.7 cm, 3–4 cm apart, ascending-oblique, sessile, narrow lanceolate, apex long-caudate, base cuneate, lowest pair of pinnae 7 cm apart from the next pinnae, often with 1–2 basiscopic short pinnules, terminal pinna same as lateral pinnae, with stalk ca. 1 cm long, pectinately pinnatifid nearly down to costa; segments in 30–35 pairs, falcate, alternate or opposite, 10 × 3.5 mm, entire; costae glabrous, abaxially grooved, with stout spines along costules; veins free, 2-forked at base; lamina pale green when dried, chartaceous. Sori linear; spore number 32; spore size 46 µm.

Distribution and conservation status: —At the edge of woods, at 500–1200 m. It is only found in Sichuan and Guizhou, Southwest China. Due to its limited distribution, we suggest it should be classified as “Near Threatened”, according to the IUCN Red List criteria ( IUCN, 2012).

Common name (assigned here):—E Mei Feng Wei Jue (峨眉Ṃ尾⁂; Chinese name)

Specimens examined: — CHINA. Guizhou: Unknown collector1835 (PE), J.M.Wang20150516001,20150516009 (IBSC).

Taxonomic notes: — Pteris omeiensis is distinct from P. kiuschiuensis by ascending and narrow lanceolate lateral pinnae. It also differs from P. oshimensis by stout stipes, more and longer pinnae and chartaceous laminae, while P. oshimensis is short and tender with herbaceous laminae, and sparser and shorter pinnae ( Fig. 3 ).

Despite the difference in plant morphology, P. omeiensis is sister to P. kiuschiuensis in the cpDNA phylogenetic tree, and they are similar in spore morphology, indicating a close genetic relationship.

Figures

FIGURE 3. Types of seven taxa in the Pteris fauriei group.A. P. austrotaiwanesis (holotype: Y.S. Chao 3255, TAIF!). B. Illustration of P. latipinna based on holotype (Y.S. Chao 2092, TAIF!). C–D. P. setuloso-costulata (iso-syntype: B. Hayata & S. Sasaki s.n., TAIF!). E–F. P. fauriei var. chinesis (holotype: C. Wang 31659, IBSC!; Isotype: PE!). G–H. P. paraemeiensis (holotype: W.P. Fang 3270, PE!). I–K. P. omeiensis (lectotype: C.S. Chang 755, PE!; syntype: T.C. Lee 3209, PE!). L. P. oshimensis (isotype: U. Faurie 4613, KYO!).