Selaginella subchaetoloma X. M. Zhou, Li Bing Zhang & Z. R. He 2023, sp. nov.
Creators: name: Fang, Shao-Li
name: Li, Yu-Xin
name: Zhang, Li-Bing
name: He, Zhao-Rong
name: Zhou, Xin-Mao
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Lycopodiopsida
Selaginellales
Selaginellaceae
Selaginella
Selaginella subchaetoloma

description: Selaginella subchaetoloma X.M.Zhou, Li Bing Zhang & Z.R.He, sp. nov. (Figs. 1, 3)
Type: — CHINA. Yunnan: Zhaotong City, Qiao Jia County, Yao Shan Town, Jionglonggou, elev. ca. 1650 m, on ditch wall in Yunnan pine (Pinus yunnanensis Franch.) forest, 16 August 2002, Zhao-Rong He & Xing-Long Liu 29625 (holotype PYU-01001254!; isotype PYU-01001255!).
Diagnosis: — Selaginella subchaetoloma is extremely similar to S. chaetoloma, but S. subchaetoloma has creeping sterile part and ascending fertile part (Figs. 1A, 2A, B) (vs. nearly creeping in S. chaetoloma) (Fig. 3D), apex of dorsal leaves abruptly short-acuminate to submucronate (Fig. 1D, J) (vs. long aristate in S. chaetoloma) (Fig. 3G), and ventral leaves slightly involute when dry (Fig. 1C, E, I) (vs. not involute when dry in S. chaetoloma) (Fig. 3I).
Plants terrestrial, evergreen, ascending from decumbent base up to 12 cm (Figs. 1A, 3A, B). Rhizophores present only at middle and lower part of the main stem, borne on ventral side in axils of branches, 0.16–0.27 mm in diam. (Fig. 1A & C). Main stem pinnately branched, 0.25–0.46 mm in diam., terete; primary leafy branches 7 or 9 pairs, 3 times pinnately branched, adjacent primary branches on main stem 0.5–1.1 cm apart (Figs. 1A, 3A, B); ultimate branches of leafy portion of main stem 1.8–3.1 mm wide. Axillary leaves on branches symmetrical, ovate, 1.1–1.3 × 0.6–0.7 mm, base broadly cuneate, margin sparsely long ciliolate (Fig. 1H). Dorsal leaves asymmetrical, those on main stems not obviously larger than those on branches; dorsal leaves on branches not approximate or contiguous, obliquely oval, 1.2–1.6 × 0.9–1.0 mm, strongly carinate, base shallowly cordate, outside margin sparsely long ciliolate at base, denticulate upwards, inside basal margin entire below middle, ciliolate-denticulate to denticulate upwards, apex abruptly short-acuminate to submucronate (Fig. 1D, J). Ventral leaves asymmetrical, those on main stem not obviously larger than those on branches; ventral leaves on branches spreading or deflexed, ovate to broadly ovate, 1.5–2.2 × 0.9–1.2 mm, apex obtuse, base nearly rounded; basiscopic margin subentire or entire; acroscopic base enlarged, broader, slightly overlapping stem and branches, margin long ciliolate, cilia 0.10–0.50 mm; apical margin denticulate (Fig. 1C, E, I). Strobili solitary or binate, terminal, compact, dorsiventrally complanate, 4.0–6.4 × 1.5– 2.0 mm (Figs. 1B, 3C). Sporophylls dimorphic, indistinctly white-margined (Fig. 1F, G); dorsal sporophylls ovatetriangular, carinate, margin long ciliolate, apex acuminate, with sporophyll-pteryx complete and ciliolate (Fig. 1K); ventral sporophylls ovate, carinate, margin ciliolate; megasporophylls in basal portion on lower side of strobilus (Fig. 1L). Megaspores slightly yellow, spherical, 284–360 μm in diam., prominent laesurae extend 1/2–2/3 of the distance to the equator, both proximal and laesurae surfaces verrucate or vermiculate ornamentation covered with the reticulate microstructure (Fig. 1M, N). Microspores orange, hemispherical, 29.7–42.7 μm in diam., both the proximal and distal surfaces densely verrucate, without obvious microstructures (Fig. 1O, P).
Additional specimens examined (paratypes):— CHINA. Yunnan: Kunming City, Luquan County, Zehei Township, Guicheng Village, elev. ca. 1550 m, 6 May 1964, W.- M. Chu et al. 1527 (PYU); Wumeng Township, elev. ca. 2150 m, 7 May 1964, W.- M. Chu, et al. 1649 (PYU); Wumeng Mountain, elev. ca. 1900 m, 15 October 1964, W.- M. Chu & J.-L. Wu 2411 (PYU); Wumeng Mountain, elev. ca. 2300 m, 15 October 1964, W.- M. Chu & J.-L. Wu 2436 (PYU); Lezuoni Village, elev. ca. 1900 m, November 1964, W.- M. Chu & J.-L. Wu 3051 (PYU); Zhaotong City, Qiaojia County, Chongxi Township, Mahong Village, elev. ca. 1500 m, 16 October 1991, W.- M. Chu & H.-Z. Yan 24404 (PYU); Qiaojiaying Township, Hetao Village, elev. ca. 2200 m, 5 August 2002, W.- M. Chu & Z.-R. He 29610 (PYU); Xiaohe Town, Yaoshan, Jionglonggou, elev. ca. 1650 m, 16 August 2002, Z.- R. He & X.-L. Liu 29625 (PYU); Sichuan: Ya’an City, Lushan County, elev. ca. 2000 m, 15 November 1963, S-H. Kung 3502 (PYU); elev. ca. 1900 m, 15 November 1963, S-H. Kung 3503 (PYU); elev. ca. 1800 m, 15 November 1963, S-H. Kung 3521 (PYU); elev. ca. 1780 m, 18 November 1963, S.- H. Kung 3522 (PYU); elev. ca. 1750 m, 18 November 1963, S.- H. Kung 3524 (PYU); Luding County, Xinglong Town, Shima Village, Zhaizigou, elev. ca. 1700 m, 8 September 1981, S.- H. Kung 6282 (PYU); Shimian County, Anshun Town, Xiaoshui Village, elev. ca. 1300 m, 11 November 1991, L.- B. Zhang & X.- S. Guo 2609 (CDBI); Shimian County, elev. ca. 1200 m, 20 November 1991, L.- B. Zhang & X.- S. Guo 2697 (CDBI).
Habitat and geographical distribution: — This species is distributed from Central Yunnan to West Sichuan in China. It was observed to grow on ground and ditch wall in Yunnan pine forest or conifer-broadleaf forest at elevations between 1200–2300 m.
Etymology: —The specific epithet subchaetoloma derives from the Latin prefix sub-, somewhat, and chaetoloma, referring to the similarities between the new species and Selaginella chaetoloma.
Vernacular name: —áfṅǐł (jin mao bian juan bai).
description: Published as part of Fang, Shao-Li, Li, Yu-Xin, Zhang, Li-Bing, He, Zhao-Rong & Zhou, Xin-Mao, 2023, Selaginella subchaetoloma (Sect. Heterostachys; Selaginellaceae), a new species from Southwest China, pp. 224-234 in Phytotaxa 603 (3) on pages 225-229, DOI: 10.11646/phytotaxa.603.3.2, http://zenodo.org/record/8166655