taxonID	type	description	language	source
00D2F038414852B6AE8CA6E01E24C429.taxon	description	Figs 3, 4, 5	en	Nong, You, Jiang, Ri-Hong, Xiong, Chi, Wei, Qiu-Jun, Wei, Gui-Yuan, Ji, Xing-Yun, Lai, Ke-Dao, Wei, Hong-Jin (2025): Polystichum oligodontum (subg. Haplopolystichum, Dryopteridaceae), a new cave fern from Guangxi, China. PhytoKeys 266: 297-310, DOI: 10.3897/phytokeys.266.156701
00D2F038414852B6AE8CA6E01E24C429.taxon	diagnosis	Diagnosis. Polystichum oligodontum is unique by the pinna acroscopic side with a shallow or nearly free lobe at the base and coarsely toothed along distal margins.	en	Nong, You, Jiang, Ri-Hong, Xiong, Chi, Wei, Qiu-Jun, Wei, Gui-Yuan, Ji, Xing-Yun, Lai, Ke-Dao, Wei, Hong-Jin (2025): Polystichum oligodontum (subg. Haplopolystichum, Dryopteridaceae), a new cave fern from Guangxi, China. PhytoKeys 266: 297-310, DOI: 10.3897/phytokeys.266.156701
00D2F038414852B6AE8CA6E01E24C429.taxon	description	Description. Plants perennial, evergreen. Rhizome short, erect, densely scaly. Fronds caespitose, 6 – 20 per rhizome, (6.5 –) 10 – 19 (– 30) cm long; stipe pale green when dry, (1.5 –) 2 – 5 (– 8.5) cm long, 0.3 – 0.5 (– 1) mm in diam. near middle, shallowly grooved adaxially, base densely covered with scales, upward scales sparse; scales ovate to oblong, brown to dark brown, apically attenuate to short-caudate, membranous, 2.5 – 4 × ca. 1.2 mm, spreading, denticulate on margin. Lamina 1 - pinnate, lanceolate, oblong-lanceolate or oblanceolate, widest at or above middle, (5 –) 7.5 – 14 (– 23) × (1.4 –) 1.8 – 2.5 (– 3) cm, slightly narrower towards base, base 0.8 – 1.7 cm wide, apex acute to short-acuminate; rachis pale green, shallowly grooved adaxially, sparsely covered with loose scales abaxially, scales lanceolate, brown, denticulate on margin. Pinnae 13 – 22 pairs, usually alternate, occasionally basal 1 – 2 pairs opposite, remote or proximate, short-stalked, stalks ca. 0.5 mm, abaxially with 1 – 2 scales similar to those on rachis, upper pinnae spreading to slightly ascending, pinnae below middle usually reflexed; lowest 2 – 4 pairs of pinnae 2 – 10 (– 14) mm apart; lowest pair sub-quadrangular, obliquely ovate or broadly flabellate, 0.8 – 5 (– 7) × 0.4 – 3 (– 5) mm; middle pinnae (6.3 –) 8.5 – 12 (– 15) × (3.5 –) 4.5 – 6 (– 8) mm, oblong, apex obtuse, subobtuse or subacute, with 1 or 2 broad, slightly mucronate teeth, base asymmetrical, acroscopic base wider, somewhat auriculate, auricles partially separated by a deep or shallow sinus, sometimes forming a nearly free lobe, with 4 – 5 acute, slightly mucronate teeth along upper margin, proximal margins of auricles slightly curved or straight, parallel or subparallel to rachis; upper acroscopic margin of pinnae nearly straight, coarsely toothed, with 2 – 3 increasingly shallow sinuses between teeth distally, teeth subacute to rounded-apiculate; basiscopic base of pinnae narrowly cuneate; basiscopic margins entire below apex, straight or nearly so, mostly acutely angled to rachis below; distal basiscopic margin curved upwards; adaxial surface glabrous, abaxial surface sparsely covered with lanceolate microscales, scales ca. 0.6 – 1 mm long, greyish-brown, denticulate on margin. Frond texture papery when dried, green adaxially; venation free, visible abaxially, indistinct adaxially, lateral veins pinnate from base upwards, dichotomous or simple above mid-rib, simple or dichotomous below mid-rib, extending into teeth, but not reaching pinna margin. Sori ca. 1 mm in diam., near pinna margins, terminal on shorter veinlets, 1 – 6 above mid-rib, often 0 – 3 below mid-rib, separate or confluent when mature. Indusia small, greyish-brown, membranous, evanescent, margin repand or slightly erose.	en	Nong, You, Jiang, Ri-Hong, Xiong, Chi, Wei, Qiu-Jun, Wei, Gui-Yuan, Ji, Xing-Yun, Lai, Ke-Dao, Wei, Hong-Jin (2025): Polystichum oligodontum (subg. Haplopolystichum, Dryopteridaceae), a new cave fern from Guangxi, China. PhytoKeys 266: 297-310, DOI: 10.3897/phytokeys.266.156701
00D2F038414852B6AE8CA6E01E24C429.taxon	distribution	Geographical distribution. Polystichum oligodontum is found so far only in three limestone caves in Guangxi Zhuang Autonomous Region, south China. Two of them are located in Xinglong Village, Fengcheng Town, Fengshan County and one of them in Renxiang Village, Jiazhuan Town, Bama County (Fig. 7).	en	Nong, You, Jiang, Ri-Hong, Xiong, Chi, Wei, Qiu-Jun, Wei, Gui-Yuan, Ji, Xing-Yun, Lai, Ke-Dao, Wei, Hong-Jin (2025): Polystichum oligodontum (subg. Haplopolystichum, Dryopteridaceae), a new cave fern from Guangxi, China. PhytoKeys 266: 297-310, DOI: 10.3897/phytokeys.266.156701
00D2F038414852B6AE8CA6E01E24C429.taxon	etymology	Etymology. The specific epithet is derived from the Latin, oligodontum, meaning “ few teeth ”, and referring to the number of the teeth on pinna margins.	en	Nong, You, Jiang, Ri-Hong, Xiong, Chi, Wei, Qiu-Jun, Wei, Gui-Yuan, Ji, Xing-Yun, Lai, Ke-Dao, Wei, Hong-Jin (2025): Polystichum oligodontum (subg. Haplopolystichum, Dryopteridaceae), a new cave fern from Guangxi, China. PhytoKeys 266: 297-310, DOI: 10.3897/phytokeys.266.156701
