Journal of Systematics and Evolution 47 (6): 581–598 (2009) doi: 10.1111/j.1759-6831.2009.00056.x Taxonomic revision of Lepisorus (J. Sm.) Ching sect. Lepisorus (Polypodiaceae) from China 1,2Xin-Ping QI 1Xian-Chun ZHANG∗ 1(State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China) 2(Graduate University of Chinese Academy of Sciences, Beijing 100049, China) Abstract The taxonomy of Lepisorus (J. Sm.) Ching sect. Lepisorus in China was revised based on herbarium specimen examinations, field observations, and microscopic study of rhizome scales, soral paraphyses, leaf epidermis, and spores. As a result, nine species were recognized: Lepisorus macrosphaerus (Baker) Ching, Lepisorus asterolepis (Baker) Ching, Lepisorus marginatus Ching, Lepisorus kuchenensis (Y.C.Wu) Ching, Lepisorus megasorus (C. Chr.) Ching, Lepisorus kawakamii (Hayata) Tagawa, Lepisorus subsessilis Ching & Y.X. Lin, Lepisorus affinis Ching, and Lepisorus nudus (Hook.) Ching. Lepisorus kawakamii (Hayata) Tagawa was reinstated; Lepisorus gyirongensis Ching & S.K. Wu and Lepisorus longus Ching were reduced to synonyms of L. nudus and L. affinis, respectively. The subdivision of Lepisorus macrosphaerus was not accepted. Rhizome scales and paraphyses are the most useful characters for species delimitation as well as for infrageneric classification. Characteristics of the leaf epidermis and spore ornamentation are usually stable and thus of great significance in understanding the relationships among groups within the genus. Key words China, Lepisorus, Lepisorus sect. Lepisorus, Polypodiaceae, taxonomic revision. The fern genus Lepisorus (J. Sm.) Ching com- quently, Lepisorus nudus (Hook.) Ching (= Pleopeltis prises approximately 40 species (Hennipman et al., nuda) should be selected as the type of Lepisorus as has 1990; Zink, 1993), with its main distribution in Asia, a been done by Farr et al. (1979) and Zink (1993). When few species in Africa and Madagascar, and one in the Yu and Lin (1997) published their first comphrensive Hawaiian islands. The genus was first subdivided by infrageneric classification of Lepisorus they unfortu- Ching (1933) into two sections based on sorus shape: nately did not accept L. nudus as type, but instead used sect. Pseudovittaria with linear sori (Lepisorus sinen- L. thunbergianus. Therefore, the names of some of their sis and Lepisorus vittarioides), and sect. Eulepisorus sections should be revised. with discrete sori comprising the remaining members Yu and Lin (1997) subdivided Lepisorus into six of the genus. Yu and Lin (1997) published a new in- sections: sect. Lepisorus, sect. Pleioomma S.L. Yu, sect. frageneric classification of Lepisorus with six sections Macrophyllon S.L. Yu, sect. Sclerophyllon S.L. Yu, sect. mainly based on rhizome scales and soral paraphyses. Pachyphyllon S.L. Yu, and sect. Hymenophyton Ching However, later, Lin (2000) divided the genus into only ex S.L. Yu & Y.X. Lin. This system, based on morphol- two sections: sect. Lepisorus and sect. Hymenophy- ogy, seems rather natural and it was partly supported by ton, based on the possession of evergreen or deciduous a phylogenetic analysis based on chloroplast sequence leaves. data (Wang et al., 2009. in press). Lepisorus was first proposed as a section of Dry- Lepisorus sect. Macrophyllon S.L. Yu is one of the naria by Smith (1846). In the protolog only two elements six sections proposed by Yu and Lin (1997). It origi- were included, Drynaria sesquipedalis and Pleopeltis nally contained only three Chinese species, Lepisorus nuda. When Ching raised Lepisorus to a genus he macrosphaerus, Lepisorus asterolepis, and Lepisorus adopted the then well-known species, Polypodium lin- marginatus. All have coriaceous and evergreen leaves, eare Thunb. (= Lepisorus thunbergianus) as the type and deciduous ovate scales, with small and dense lu- which is contrary to the code, because the type should mina. Some species clearly belonging to this section, be chosen from the two elements cited by Smith. Conse- such as Lepisorus affinis Ching and Lepisorus kuch- enensis (Y.C. Wu) Ching, were put into sect. Pachy- phyllon S.L. Yu based on their lanceolate scales, with Received: 22 March 2009 Accepted: 7 July 2009 clathrate lumina. However, both of these species with ∗ Author for correspondence. E-mail: [email protected]; Tel: 86-10- evergreen leaves can easily be distinguished from the 62836291; Fax: 86-10-62836291. C 2009 Institute of Botany, Chinese Academy of Sciences 582 Journal of Systematics and Evolution Vol. 47 No. 6 2009 other species of sect. Pachyphyllon, typified by Lep- sect. Pachyphyllon, and Lepisorus subsessilis Ching & isorus bicolor with deciduous leaves. Recent molec- Y.X. Lin. All of these species are mainly distributed in ular analysis also found L. macrosphaerus, Lepisorus China with L. nudus and L. macrosphaerus extending megasorus, Lepisorus kawakamii and L. nudus form- into the Himalayas. ing one clade with high support (Kreier et al., 2008). The scales of L. macrosphaerus and L. kawakamii are ovate, while those of L. megasorus and L. nudus are 1 Material and methods lanceolate. Although different in shape, these scales are similar in texture and lumina pattern. Based on its char- 1.1 Rhizome scales, leaf scales, and paraphyses acters of scales, paraphyses, leaf epidermis, and spores, For the study of rhizome scales, leaf scales, and L. nudus should be a member of sect. Macrophyllon. paraphyses, herbarium material for examination was Therefore, sect. Macrophyllon is a synonym of sect. taken from the following herbaria: GAUA, GXMI, IBK, Lepisorus which is typified by L. nudus. IBSC, IMC, KUN, PE, PYU, TI, US, and WUK. For The latest taxonomic revision of the Chinese each species, between 20 and 30 samples per charac- species of Lepisorus was published by Lin (2000), and ter were studied and selected from different specimens; the most reliable infrageneric classification was pub- photographs were taken with a Nikon LV-TV camera lished by Yu and Lin (1997). During our revision study, connected to a stereo microscope and computer, and we have studied almost all of the Asian species of Lep- measured using Nikon Act-1. Taxonomical terminol- isorus except some from the Malaysian regions. Our ogy generally followed Lellinger (2002). observations of macromorphology and micromorphol- ogy (such as leaf epidermis and spores) confirmed that 1.2 Leaf epidermis the genus can be naturally subdivided into several sec- Mature leaves were taken from 22 herbarium (PE) tions based mainly on characters of the rhizome scales specimens, representing all nine species of sect. Lep- and soral paraphyses, and in agreement with the classi- isorus (Table 1). Lepisorus scolopendrium (Ching) fication of Yu and Lin (1997) in most part. As a result of Mehra & Bir, belonging to sect. Pachyphyllon,was part of our taxonomic revision of the genus from China, used for comparison because it has similar scales as nine species were recognized in sect. Lepisorus, which L. kuchenensis and always keyed out together in identi- includes all the species of sect. Macrophyllon, part of fication keys in former publications. Material for light Table 1 Vouchers for leaf epidermis of Lepisorus sect. Lepisorus Taxon Locality Voucher L. macrosphaerus (Baker) Ching Pingwu, Sichuan, China () H.L. Tsiang () 11118 (PE) Lushui, Yunnan, China () X.C. Zhang et. al () 4520 (PE) Medog,ˆ Xizang, China () B.S. Li () 3215 (PE) L. marginatus Ching Wuxi, Chongqing, China () X.P. Qi () 5178 (PE) Ankang, Shaanxi, China ()P.Y.Li() 3199 (WUK) Barkam, Sichuan, China ()X.Li() 72707 (PE) L. asterolepis (Baker) Ching Mt. Emei, Sichuan, China () K.H. Shing () 1643 (PE) Mt. Jinfo, Chongqing, China () X.P. Qi () 4587 (PE) Daguan, Yunnan, China () NE Yunnan Exped. () 1089 (PE) L. kawakamii (Hayata) Tagawa Taihotou, Taiwan, China ()M.Tagawa47(PE) L. megasorus (C. Chr.) Ching Taizhong, Taiwan, China () W. Hancock 31 (PE) L. kuchenensis (Y. C. Wu) Ching Mt. Yaoshan, Guangxi, China ()C.Wang() 40271 (PE) L. subsessilis Ching & Y. X. Lin Fengshan, Guangxi, China ()Z.T.Li() 601709 (PE) Baise, Guangxi, China () Baise Exped. () 01558 (PE) L. nudus (Hook.) Ching Mussoorie, India S.P. Khular 3 (PE) Simla, India X.C. Zhang () 2754 (PE) L. gyirongensis Ching & S. K. Wu Gyirong, Xizang, China () Qinghai-Xizang Complex Exp. (Geobot. Sect.) () 5184 (PE) L. affinis Ching Mt. Wuzhi, Hainan, China () C L. Tso & N.K. Chun (, ) 44067 (PE) Mt. Wuzhi, Hainan, China () X.C. Zhang () 1681 (PE) L. longus Ching Mt. Diaoluo, Hainan, China () Diaoluoshan Exped. ()3302 (PE) Lingshui, Hainan, China () Hainan Exped. ()1925 (PE) Lingshui, Hainan, China () S.Y. Dong () 355 (PE) L. scolopendrium (Ching) Mehra & Bir Binchuan, Yunnan, China () X.P. Qi () Q007 (PE) C 2009 Institute of Botany, Chinese Academy of Sciences QI & ZHANG: Taxonomic revision of Lepisorus sect. Lepisorus 583 Table 2 Vouchers for spore observations of Lepisorus sect. Lepisorus Taxon Locality Voucher L. macrosphaerus Malipo, Yunnan, China () K.M. Feng () 12714 (PE) Medog,ˆ Xizang, China () B.S. Li et al. () 3215 (PE) L. marginatus Barkam, Sichuan, China ()X.Li() 72707 (PE) Songxian, Henan, China () Henan Exped. () 1898 (PE) L. asterolepis Mt. Emei, Sichuan, China () Ann 815 (PE) Mt. Jinfo, Chongqing, China () X.P. Qi () 4590 (PE) Daguan, Yunnan, China () NE Yunnan Exped. () 491 (PE) L. kawakamii Hualian, Taiwan, China ()T.C.Chen() 9862 (PE) L. megasorus Hualian, Taiwan, China ()T.C.Chen() 12733 (PE) L. kuchenensis Mt. Yaoshan, Guangxi, China ()C.Wang() 40271 (PE) Taizhong, Taiwan, China () Imaseki 70500 (TI) L. subsessilis Fengshan, Guangxi, China ()Z.T.Li() 601733 (PE) L. nudus Milke Danda, Nepal R.L. Fleming 2087 (PE) L. affinis Mt. Wuzhi, Hainan, China () C.L. Tso & N.K. Chun (, ) 44067 (PE) Baisha, Hainan, China () E Hainan Exped. () 512 (PE) L. longus Mt. Diaoluo, Hainan, China () Mt Diaoluo Exped. () 3302 (PE) L. scolopendrium Maguan, Yunnan, China () S.K. Wu () 61–3578 (PE) microscopy were boiled in water before being macer- L. macrosphaerus (GZ = Guizhou, YN = Yunnan, ated in 35% NaOCl solution. Pieces of epidermis were XZ = Xizang).