Porella densifolia (Steph.) S.Hatt. subsp. densifolia, J. Jap. Bot.

Qian, Kai & Zhu, Rui-Liang, 2017, The status of Porella subparaphyllina J. S. Lou (Marchantiophyta, Porellaceae), a poorly known species endemic to Yunnan, China, Phytotaxa 319 (3), pp. 299-300 : 299-300

Porella densifolia (Steph.) S.Hatt. subsp. densifolia, J. Jap. Bot. 20: 109. 1944.

Basionym:— Madotheca densifolia Steph., Mém. Soc. Nat. Sci. Nat. Math. Cherbourg 29: 219. 1894 ( Stephani 1894). Type:— CHINA. Yunnan Prov.: “bois de Kutui, au-dessus de Mo so You”, 19 July 1889, P.J.M. Delavay s.n. (holotype: G012063!).

= Porella subparaphyllina J.S.Lou, Acta Phytotax. Sin. 25(6): 483. 1987 ( Lou 1987). Type:— CHINA. Yunnan Prov.: Gongshan Co., Dulongjiang, 1900 m, 2 Sept. 1982, M.-Z. Wang 11493-b (holotype: PE!). syn. nov.

Representative specimens examined:

Specimen initially identified as Porella subparaphyllina :— CHINA. Yunnan, Gongshan Co., Dulongjiang Village, 2000 m, M.-Z. Wang 11535-a (PE).

Representative specimens of Porella densifolia subsp. densifolia :— CHINA. Anhui, Taiping Co., Jiulongfeng Nature Reserve , 790 m, on fallen wood, 30 Apr. 2016, X.- Q. Shi 20160430-48 ( HSNU). Fujian, Dehua Co. , Daiyunshan Nature Reserve , 860 m, on tree base, 28 Oct. 2009, X.- Q. Zhang et al. 20091028-42 ( HSNU). Guangxi, Napo Co. , Baidu Town , Nonglong Village , 23°14.235 ′ N, 105°32.490 ′ E, 1244 m, on rock with a thin layer of soil, 18 Aug. 2013, J. Wang et al. 20130818-15 ( HSNU). Xizang, Linzhi Prefecture , Yaluzangbu (Yarlung Tsangpo) Grand Canyon National Nature Reserve , Pailong Town , near Daguaiwan , 30°01.207 ′ N, 95°00.518 ′ E, 2018 m, on rock, 26 Aug. 2014, J. Wang et al. 20140826-9 ( HSNU) ; Chayu (Zayu) Co., Cibagou National Nature Reserve, 28°33.725 ′ N, 97°04.675 ′ E, 1673 m, on rock, 29 Aug. 2014, J. Wang et al. 20140829-164 ( HSNU). Yunnan, Gongshan Co , Dulongjiang Town , from Kongdang Village to Longyuan Village , 27°53.176’ N, 98°20.555’ E, 1478 m, on tree trunk, 6 Jul. 2012, J. Wang et al. 20120706-38 ( HSNU) ; Gongshan Co., Dulongjiang Town, near Xiongdang Village , 28°06.224 ′ N, 98°19.325 ′ E, 1943 m, on tree bark, 19 Jan. 2015, J. Wang et al. 20150119-97 ( HSNU) ; Gongshan Co., Dulongjiang Town, near Dinggei Village , 27°57.320 ′ N, 98°19.730 ′ E, 1612 m, on tree trunk, 21 Jan. 2015, J. Wang et al. 20150121-78 ( HSNU) ; Gongshan Co., Dulongjiang Town, from Qinlandang Village to Maku Village by the old road, 27°40.869 ′ N, 98°17.489 ′ E, 1601 m, on rock, 23 Jan. 2015, J. Wang et al. 20150123- 129 ( HSNU) ; Gongshan Co., Bingzhongluo Town , 28°00.560 ′ N, 98° 35.704 ′ E, 1943 m, on tree trunk, 20 Sept. 2010, Y. Yu 20100920-14 ( HSNU) ; Lushui Co., from Pianma Town to Gangfang Village , near Ganhuoluo Bridge , 26°03.487 ′ N, 98°37.163 ′ E, 2091 m, on rotten wood, 26 Jan. 2015, J. Wang et al. 20150126-40 ( HSNU) ; Shangri-La (Xianggelila) City, Luoji Town, from Niru Village to Selie Lake . 27°58 ′ 12.34 ″ N, 100°03 ′ 18.27 ″ E, 2819 m, 19 Sept. 2016, Y.- L. Xiang 20160919-7 ( HSNU) ; Weixi Co., Weideng Town, near Luowu Village , 27°05.156 ′ N, 99°04.844 ′ E, 2327 m, on tree trunk, 27 Jan. 2015, J. Wang et al. 20150127-7 ( HSNU) ; Yulong Co., Mingyin Town, 27°13.336 ′ N, 100°21.094 ′ E, 2805 m, on rock, 14 Apr. 2013, J. Wang & K. Qian 20130414-8 ( HSNU). Zhejiang, Linan Co , Tianmushan Nature Reserve , near Chanyuansi , 30°19 ′ 20.98 ″ N, 119°26 ′ 30.72 ″ E, 368 m, on rock, 24 Apr. 2013, R.- L. Zhu & C.- X. Zhao 20130424-7 ( HSNU) .

Notes:— Porella subparaphyllina was a poorly known species which was known only from the type specimens from northwestern Yunnan ( Piippo et al. 1998; Jia & He 2013). It was omitted in Piippo’s (1990) checklist of Chinese hepatics and Gao & Cao’s (2000) Flora Yunnanica. Porella densifolia subsp. densifolia is characterized by the densely imbricate leaf lobes, leaf lobules and underleaves. The apex of leaf lobes, however, are rather variable even on the same stem: usually acute to accumulate with 1–2(–4) teeth, but occasionally obtuse to rounded as discussed in Pócs (1968) and Luo (1989). An examination of numerous specimens reveal that the typical Porella densifolia subsp. densifolia has remarkable leaf lobules which are recurved along the distal lateral margin in herbarium specimens. Porella densifolia was considered to be a complex and its infraspecific treatment is still not satisfactory ( Hentschel et al. 2007). A study on the status of the Indian Porella densifolia subsp. subsp. andamana and the Himalayan P. densifolia subsp. appendiculata and related taxa is in progress.