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Abstract： Hong Kong， located at the southern edge of Guangdong and the northern fringe of the tropics， has suffered from large scale habitat destruction throughout most of its history of inhabitance and has only been in recovery for several decades. It has a long history of botanical exploration， and up to now， more than 2 170 native vascular plant species have been recorded in its territories. Nonetheless， taxa new to science and new records are increasingly being discovered and described. During recent field trips， we found ten new records of vascular plants for Hong Kong. The newly recorded species or varieties are Haplopteris elongata （Swartz） E. H. Crane， Amydrium sinense （Engl.） H. Li， Pothos repens （Lour.） Druce， Cyclea sutchuenensis Gagnep.， Dumasia truncata Siebold & Zucc.， Aucuba obcordata （Rehder） Fu ex W. K. Hu et Soong， Ficus stenophylla Hemsl.， F. gasparriniana var. esquirolii （H. L¨?v. & Vaniot） Corner， Ilex ficifolia C. J. Tseng ex S. K. Chen et Y. X. Feng and Paraprenanthes sororia （Miq.） C. Shih； Amydrium Schott， Dumasia DC. and Paraprenanthes C. C. Chang ex C. Shih are also newly recorded genera in Hong Kong. Our findings enrich the flora of Hong Kong and underline the importance and the need to conserve remnant vegetation patches and highlights the need to pay special attention to extremely small populations.
Key words： new records， vascular plants， flora， conservation， biodiversity
Hong Kong， located at the southern coast of Guangdong Province， lies between 22??08??-22??35?? N and 113??49??-114??31?? E， with the highest peak Tai Mo Shan reaching 957 m above sea level. The total land area is about 1 105.7 km2， including more than 260 islands （Government of Hong Kong SAR， China， 2017）. Although well known as a metropolis， only less than 25% of its land has been developed， and about 78.7% of its area is covered by vegetation. It has a subtropical monsoon climate， and the mean annual rainfall ranges from 1 600 to 3 000 mm （Hong Kong Observatory， Hong Kong SAR， China， 2017）. Complex topography， warm climate and the remarkable variation of precipitation have fostered a diverse flora in this region.
Hong Kong lies at the northeast corner of the Indo??Burma Biodiversity Hotspot （Myers et al， 2000） and is rich in plant species. The original vegetation is evergreen or semi??evergreen forest （Zhuang & Corlett， 1997?? Xing et al， 1999）， but it was largely destroyed in the past centuries and almost clear??cut during the Japanese Occupation （1942-1945） with less than 1% forest cover remaining on Hong Kong??s highest mountain Tai Mo Shan （Zhuang & Corlett， 1997?? Abbas et al， 2016）. Since then， secondary forest has slowly expanded from extremely small remnant forest patches and isolated trees in remote ravines， leading to a gradual increase in forest cover during the last 70 years （Abbas et al， 2016）. According to a recent land survey， woodland accounted for 24.9%， shrubland for 23.6% and grassland for 17.3% of the total land area （Planning Department， Hong Kong SAR， China， 2017）. Botanical studies have a long history in Hong Kong. As early as in 1816， C. Abel collected herbarium specimens from Hong Kong （Xing et al， 1999）. Since 1841， a number of well??known collectors carried out botanical collection in this region （Hong Kong Herbarium， Agriculture， Fisheries and Conservation Department， Hong Kong SAR， China， 2017）. In 1857， The Botany of the Voyage of H. M. S. Herald， one of the earliest plant accounts of Hong Kong written by B. C. Seemann was published， in which 773 species were recorded （Seemann， 1857）. In 1861， Flora Hongkongensis， the first flora of Hong Kong written by George Bentham was published， and 1 056 taxa of vascular plants were included （Bentham， 1861）. Although a number of botanists including Prof. Hu Shiu Ying collected specimens for decades after World War ?ò， the flora remained largely under??explored. Prof. Xing Fuwu collected 3 500 specimens from 1996 to 1998 and together with the previously collected voucher specimens， and identified 1 884 species of native seed plants， belonging to 876 genera， of which 106 species were new records for Hong Kong （Xing et al， 1999）. In 2011， AFCD （Agriculture， Fisheries and Conservation Department， Hong Kong SAR， China， 2017） published the Flora of Hong Kong in four volumes. According to the latest Check List of Hong Kong Plants， the number of native vascular plants species and varieties has increased to 2 175 （Hong Kong Herbarium， Hong Kong SAR， China， 2012）.
Meanwhile， species new to science are still being described， for example， Syzygium impressum （Xia et al， 2008）， Carpinus insularis （Tong et al， 2014）， Gastrochilus kadooriei （Kumar et al， 2014）， Thismia hongkongensis （Mar & Saunders， 2015）， and new records （e. g. Yan et al， 2006； Gale et al， 2013 ） are continuously being reported.
During recent plant exploration trips in remote parts of Hong Kong， we found ten newly recorded taxa， three newly recorded genera to this region. The voucher specimens are deposited in Kadoorie Farm & Botanic Garden Herbarium （KFBG）. This article aims to report these discoveries.
1 Pteridaceae
Haplopteris elongata （Swartz ） E. H. Crane （Fig. 1： A）
In Syst. Bot. 22： 514.1998； FRPS， 3（2）： 25， pl. 7： 1： 4； FOC， 2-3： 255. ??Vittaria elongata Sw. In Syn. Fil. 109， 302. 1806.
Distribution： China （Fujian， Guangdong， Guangxi， Hainan， Hong Kong， Taiwan， Tibet， Yunnan）， Australia， Indonesia， Japan， Laos， Madagascar， Malaysia， Myanmar， Nepal， Philippines， Sri Lanka， Thailand and Vietnam. Ecology： Epiphytic on tree trunks or growing on the shady and moist side of rocks， shade tolerant.
Specimens seen： China. Hong Kong， New Territories， Ma On Shan， Luk Chau Shan， on the moist side of rocks， alt. 403 m， 4 March 2017， （Liu Jingang， JG0212， KFBG）.
Notes： Fern， epiphytic or epilithic. Rhizome long， creeping. Fronds clustered， drooping； lamina leathery， ribbon??like， up to 1 m long. Soral line marginal， immersed in deep groove， open outward.
It differs from Haplopteris flexuosa （F¨?e） E. H. Crane by having much longer lamina， and marginal soral line immersed in groove. H. flexuosa has been recorded as early as 1912 in Hong Kong and is common， while H. elongata is rare. We only found about ten small clumps scattered among the Luk Chau Shan rock jungle， growing with Asplenium crinicaule Hance.
2 Araceae
2. 1 Amydrium sinense （Engl.） H. Li. （Fig. 1： B）
In FRPS， 13（2）： 23， pl. 4： 8-10. 1979； FOC， 23： 10， 2010； ?? Scindapsus sinensis Engl. in Engl.， Bot. Jahrb. 29： 234. 1900.
Distribution： China （Hubei， Hunan， Hong Kong， Guangxi， Guangdong， Guizhou， Sichuan， Yunnan）， Vietnam.
Ecology：Growing upon or attached to trees or rocks， shade tolerant. Flowering in June-July， fruiting in July-November.
Specimens seen： China. Hong Kong， New Territories， Tai Po， Ng Tung Chai， next to the Main Fall， alt. 472 m， 14 July 2017， （Zhang Jinlong & Zhu Huiling etc， JL1194， KFBG）.
Notes： Herbaceous liana. Stem slender， climbing on rocks through fleshy aerial roots. Leaves distantly arranged， falcate??lanceolate， 13-2 ?? 5-8 cm， base subrounded， margin entire， apex acute； adaxially bright green， abaxially yellowish green. Petiole base sheathing.
Amydrium is a newly recorded genus to Hong Kong. There are five species in this genus， in which two have been found in South China. A. hainanense， another species reported from South China， differs from this species in having round to oval perforations on both sides along the midrib.
2. 2 Pothos repens （Lour.） Druce （Fig. 1： C）
In Rept. Bot. Exch. Club. Brit. Isles. 4： 641. 1917； FRPS， 13（2）： 20， pl. 3： 9. 1979； FOC， 23： 8， 2010； FGD， 9： 180， 2009； FHN， 4： 130， fig. 1034， 1977.
Distribution： China （Guangdong， Guangxi， Hainan， Hong Kong， Yunnan）， Laos， Vietnam.
Ecology： Climbing on trees or creeping over rocks in moist forests. Flowering in March-April， fruiting in May-July.
Specimens seen： China. Hong Kong， New Territories， Lantau Island， Tai O， alt. 38 m （7 September 2017， Craig Williams， CW0530， KFBG）. Notes： Epiphytic lianas， more than 10 m long. Stem angulate. Phyllode ca. 13-15 cm ?? 1 cm； leaf blade lanceolate， 3-5 cm ?? 1 cm； primary veins parallel. Leaves on young shoots much smaller， petioles elliptical. Spadix cylindric. This species differs from Pothos chinensis （Raf.） Merr. in having a much longer phyllode， which is 3-4 times longer than leaf blade.
3 Menispermaceae
Cyclea sutchuenensis Gagnep. （Fig. 1： D， E， F）
In Bull. Soc. Bot. France 55： 37， 1908； Diels in Engler， Pflanzenreich IV. 94： 319， 1910； FRPS 30（1）： 75， pl. 16： 6-11， 1996； FOC 7： 28， 2008； FGD 1： 45， fig. 45， 1987.
Distribution：China （Guangdong， Guangxi， Guizhou， Hong Kong， Hubei， Hunan， Sichuan， Yunnan）.
Ecology： Forests， forest margins， shrublands. Flowering in early summer and fruiting in autumn.
Specimens seen： China. Hong Kong， New Territories， Lantau Island， Wong Lung Hang Country Trail， alt. 604 m， （10 January 2017， Zhang Jinlong & Zhu Huiling， JL1085， KFBG）； the same location， （11 May 2017， Liu Jingang， JG0293， KFBG）.
Notes： Vines， glabrous， sometimes bracts pubescent， leaf blade lanceolate， 5-15 ?? 2-5.5 cm， thinly leathery or papery， with 3-5 palmate veines， base rounded. Male flowers： sepals 4 or 5， connate at base. This species differs from Cyclea hypoglauca （Schauer） Diels in having lanceolate leaf blades and a larger endocarp.
4 Fabaceae
Dumasia truncata Siebold & Zucc. （Fig. 1： G）
In Abh. Akad. Wiss. Monchen 4（2）： 119. 1843； FRPS 41： 253， 1995； FOC 10： 243， 2010；
Distribution： China （Anhui， Fujian， Taiwan， Guangdong， Guangxi， Henan， Hong Kong， Hunan， Hubei， Jiangxi， Shaanxi， Zhejiang）， Japan， Korea.
Ecology： Mountain slope， forest margins or streamsides， understorey. Flowering in August-September， fruiting in October-November.
Specimens seen： China. Hong Kong， New Territories， Tai Po， Ng Tung Chai， between the Main Fall and Scatter Fall， alt. 472 m （14 July 2017， Zhang Jinlong & Zhu Huiling etc.， JL1195， KFBG）
Notes： Perennial twining herbs， glabrous. The shape of leaflet is similar to Dumasia hirsuta， but the latter can be easily distinguished by hirsute stems and petioles （Pan & Zhu， 2010）. Only a very small population with less than five individuals along the hiking trail from Ng Tung Chai to Tai Mo Shan was observed. Dumasia is a newly recorded genus to Hong Kong.
5 Garryaceae
Aucuba obcordata （Rehder） Fu ex W. K. Hu et Soong. （Fig. 2： A） Checklist of Herbarium Specimens of Hubei. 166. 1964； Flora Sichuanica 1： 395. pl. 149： 6-8， 1981； FRPS， 56：19， 1990； FOC， 14： 226， 2005.
Distribution： China （Guangdong， Guangxi， Guizhou， Hong Kong， Hubei， Hunan， Shaanxi， Sichuan， Yunnan）.
Ecology： Forests， in shady and moist habitat. Flo??wering in March-April and fruiting in September-November.
Specimens seen： China. Hong Kong， New Territories， Tai Po， Tai Mo Shan， Tai Shing Stream， alt. 695 m. （21 January 2017， Hang Kingyeung， HKY0057， KFBG）.
Notes： Shrubs or small trees. Leaves obcordate or obovate， （4-） 8-14 ?? （2-） 4.5-8 cm， thickly papery to subleathery， base narrowly cuneate， margin coarsely dentate， sinuate between teeth， apex truncate orobcordate. This species could be easily distinguished from Aucuba chinensis Benth.， another species found in Hong Kong， by the shape of leaf apex.
6 Moraceae
6. 1 Ficus stenophylla Hemsl. （Fig. 2： B）
In Hook. Icon. Pl. 26： t. 2536. 1897. FHN， 2： 397. 1965； FGD， 1：207， fig. 234， 1987； FRPS， 23（1）： 151， pl. 37： 1-4 1998； FOC， 5： 58， 2003.
Distribution： China （Fujian， Taiwan， Guangdong， Guangxi， Guizhou， Hainan， Hong Kong， Hubei， Hunan， Jiangxi， Yunnan， Zhejiang）， Laos， Thailand， Vietnam.
Ecology： Forest， valleys. Flowering and fruiting in May-January of the following year.
Specimens seen： China. Hong Kong， New Territories， Wang Shan Keuk Ha Tsuen to Luk Keng， alt.
258.5 m， （6 December 2016， Zhang Jinlong， JL0990， KFBG）； Hong Kong， Mount Parker， 365 m， （14 December 2016， Liu Jingang， JG0454， KFBG）； Hong Kong， Mount Parker， （2 September 2008， Y. W. Lam， HK0043963， HK）.
Notes： Shrubs. This species is similar to Ficus variolosa Lindl. ex Benth.， but differs in having thin papery leaves and the blades are usually much narrower.
6. 2 Ficus gasparriniana var. esquirolii （H. L¨?v. & Vaniot） Corner （Fig. 2： C）
In Gard. Bull. Sing. 17： 428， 1959； FRPS， 23（1）： 145， pl. 34： 6， 1998； FOC， 5：57， 2003.
Distribution： China （Guangdong， Guangxi， Guizhou，Hong Kong， Hunan， Jiangxi， Sichuan， Yunnan）.
Ecology： Along hiking trails in forest margin. Understorey or growing in shrubland on the mountain ridge. Flowering in May-July.
Specimens seen： China. Hong Kong， New Territories， Ma On Shan， Wong Chuk Yeung； Along MacLehose Trail Section IV， on forest margin， alt. 246 m. （22 September 2016， Zhang Jinlong， JL0707， KFBG）； Ma On Shan， Wong Chuk Yeung， （28 April 2005， P. Chow， HK0044009， HK）. Notes： Although this taxon has been identified as Ficus gasparriniana var. esquirolii， it is closer to the type specimen of F. cehengensis S. S. Chang （Cao Z.Y.， 766， PE00024116， PE00024117， PE）. We adopted the treatment of Flora of China， where Ficus cehengensis has been treated as a synonym of F. gasparriniana var. esquirolii. The fruits of our specimens are globose and tubercular. This variety is similar to F. stenophylla Hemsl.， but leaves are 3-4 times broader， fruits are tubercular and attached to the stem with relatively robust pedicel. In comparison， the exocarp of F. stenophylla is almost smooth. Further investigation might be needed to clarify the identity of this taxon.
7 Aquifoliaceae
Ilex ficifolia C. J. Tseng ex S. K. Chen et Y. X. Feng （Fig. 2： D）
In Acta Phytotax. Sin. 37 （2）： 143， 1999； FRPS， 45（2）：34， pl. 6： 6-9， 1999； FOC， 11：378， 2008； ?? Ilex ficifolia C. J. Tseng in J. Xiamen Univ. Nat. Sci. 9（4）： 306， f. 3， 1962.
Distribution： China （Fujian， Guangdong， Guangxi， Hong Kong， Hunan， Jiangxi， Zhejiang）.
Ecology： In woodland. Flowering in May-June， fruiting in September-November.
Specimens seen： China. Hong Kong， New Territories， Lantau Island， Ngong Ping 360 Rescue Trail， alt. 425 m. （13 October 2016， Zhang Jinlong， JL0764， KFBG）.
Notes： Trees or shrubs. Leaf blade elliptic or oblong-elliptic， glabrous， margin sparsely and inconspicuously serrulate. Peduncles longer than pedicels. This species is similar to Ilex suaveolens （H. L¨?v.） Loes.， but differs in having shorter peduncles and shiny leaves.
8 Asteraceae
Paraprenanthes sororia （Miq.） C. Shih. （Fig. 2： E， F， G）
In Acta Phytotax. Sin. 26： 422. 1988； FOC， 21： 228， 2011. ??Paraprenanthes pilipes （Migo） Shih in Act. Phytotax. Sin. 26： 424. 1988； FRPS， 80（1）： 181， 1997； ??Prenanthes pilipes （Migo） Y. R. Ling， FGD， 8： 266， 2007.
Distribution： China （Anhui， Chongqing， Fujian， Guangdong， Guangxi， Guizhou， Hainan， Hong Kong， Hubei， Hunan， Jiangsu， Jiangxi， Sichuan， Taiwan， Xizang， Yunnan， Zhejiang）， Japan， South Korea， Vietnam.
Ecology： Roadsides， mountain slopes， shrublands， valleys， understorey of forests. Flowering and fruiting in May-August.
Specimens seen： China. Hong Kong， New Territories， Tai Po， Tai Mo Shan， along the trail between Ng Tung Chai and the pavilion beside Tai Mo Shan Forest Track. In open habitat close to stream. （27 May 2017， Liu Jingang & Hang Kingyeung， JG0301， KFBG） Notes： This is the most widespread species in this genus. The specimen was identified as Paraprenanthes pilipes by fo??llowing the keys in FRPS， but P. pilipes has been treated as a synonym of P. sororia in Flora of China. Only a small population was observed on Tai Mo Shan. Paraprenanthes is a newly recorded genus to HK.
Acknowledgements We are thankful to Stephan GALE， Craig WILLIAMS， Mandy WONG and WONG Shan for the assistance in collecting herbarium specimens. We thank PANG Kuen Shum （HK）， Rachel CHEUNG （HK） and ZENG Feiyan （SCIB） for kindly helping during specimen examination. FUNG Ka Yan and WONG Sai Fong （KFBG） for processing the herbarium specimens， and TAN Yunhong （HITBC）， JIANG Kaiwen， TU Tieyao （SCIB）， HU Aiqun （HKU）， PENG Hua （KUN） for helpful discussions. This study was sponsored by Kadoorie Farm and Botanic Garden.
References：
ABBAS S，NICHOL JE， FISCHER GA， 2016. A 70??year perspective on tropical forest regeneration ??J??. Sci Total Environ， 544：544-552.
BENTHAM G， 1861. Flora Hongkongensis ??M??. London： Lovell Reeve.
GALE SW， KUMAR P， HU AQ， et al， 2013.Cheirostylis pusilla （Orchidaceae）， a new record for Hong Kong of China ??J??. Kew Bull， 68：325-330.
Government of Hong Kong SAR， China， 2017. GovHK， www. gov. hk； https：//www.gov.hk/en/about/abouthk/facts.htm.
Hong Kong Herbarium， Hong Kong SAR， China， 2012. Checklist of Hong Kong plants ??M??. Hong Kong： Agriculture and Fisheries Department.
Hong Kong Herbarium， Agriculture， Fisheries and Conservation Department， Hong Kong SAR， China， 2017. http：//www.herbarium.gov.hk/AboutUs.aspx.
Hong Kong Observatory， Hong Kong SAR， China， 2017. http：//www.weather.gov.hk/cis/climahk_e.htm.
Planning Department， Hong Kong SAR， China， 2017. http：//www.pland.gov.hk/pland_tc/info_serv/statistic/landu.html.
KUMAR P， GALE SW， KOCYAN A， et al， 2014. Gastrochilus kadooriei （Orchidaceae）， a new species from Hong Kong， with notes on allied taxa in section Microphyllae found in the region ??J??. Phytotaxa， 164（2）： 91-103.
MAR SS， SAUNDERS RMK， 2015. Thismia hongkongensis （Thismiaceae）： a new Mycoheterotrophic species from Hong Kong， China， with observations on floral visitors and seed dispersal ??J??. PhytoKeys， 46：21-33.
MYERS N， MITTERMEIER RA， MITTERMEIER CG， et al， 2000. Biodiversity hotspots for conservation priorities ??J??. Nature， 403：853-858.
PAN B， ZHU XY， 2010. Taxonomic revision of Dumasia （Fabaceae， Papilionoideae） ??J??. Ann Bot Fenn， 47（4）：241-256. SEEMANN B， 1857. The botany of the voyage of H. M. S. Herald ??M??. London： Lovell Reeve.
TONG YH， PANG KS， XIAN NH， 2014. Carpinus insularis （Betulaceae）， a new species from Hong Kong ??J??. J Trop Subtrop Bot， 22（2）： 121-124. ?????????? ?í?¨???? ???????? 2014. ????è????????????????????ì?úè? ??J??. ???????????????§±¨??22（2）：121-124.??
XIA NH， DENG YF， YIP KL， 2008. Syzygium impressum （Myrtaceae）， a new species from Hong Kong ??J??. J Trop Subtrop Bot， 16（1）：19-22. ????????， ????·?， ???ú??， 2008. ??????????????????-°????àé? ??J??. ???????????????§±¨， 16（1）：19-22.??
XING FW， CORLETT RT， CHAU KC， 1999. Study on the flora of Hong Kong ??J??. J Trop Subtrop Bot， 7（4）：295-307. ????????， CORLETT RT， ??????， 1999. ?????????????? ??J??. ???????????????§±¨， 7（4）：295-307.??
YAN YH， NG SC， XING FW， 2006. Additions to fern flora of Hong Kong， China ??J??. Guihaia， 26（1）：5-7. ???????è， ??????， ??????， 2006. ?????§?à?????????? ??J??. ???÷????， 26（1）：5-7.??
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Key words： new records， vascular plants， flora， conservation， biodiversity
Hong Kong， located at the southern coast of Guangdong Province， lies between 22??08??-22??35?? N and 113??49??-114??31?? E， with the highest peak Tai Mo Shan reaching 957 m above sea level. The total land area is about 1 105.7 km2， including more than 260 islands （Government of Hong Kong SAR， China， 2017）. Although well known as a metropolis， only less than 25% of its land has been developed， and about 78.7% of its area is covered by vegetation. It has a subtropical monsoon climate， and the mean annual rainfall ranges from 1 600 to 3 000 mm （Hong Kong Observatory， Hong Kong SAR， China， 2017）. Complex topography， warm climate and the remarkable variation of precipitation have fostered a diverse flora in this region.
Hong Kong lies at the northeast corner of the Indo??Burma Biodiversity Hotspot （Myers et al， 2000） and is rich in plant species. The original vegetation is evergreen or semi??evergreen forest （Zhuang & Corlett， 1997?? Xing et al， 1999）， but it was largely destroyed in the past centuries and almost clear??cut during the Japanese Occupation （1942-1945） with less than 1% forest cover remaining on Hong Kong??s highest mountain Tai Mo Shan （Zhuang & Corlett， 1997?? Abbas et al， 2016）. Since then， secondary forest has slowly expanded from extremely small remnant forest patches and isolated trees in remote ravines， leading to a gradual increase in forest cover during the last 70 years （Abbas et al， 2016）. According to a recent land survey， woodland accounted for 24.9%， shrubland for 23.6% and grassland for 17.3% of the total land area （Planning Department， Hong Kong SAR， China， 2017）. Botanical studies have a long history in Hong Kong. As early as in 1816， C. Abel collected herbarium specimens from Hong Kong （Xing et al， 1999）. Since 1841， a number of well??known collectors carried out botanical collection in this region （Hong Kong Herbarium， Agriculture， Fisheries and Conservation Department， Hong Kong SAR， China， 2017）. In 1857， The Botany of the Voyage of H. M. S. Herald， one of the earliest plant accounts of Hong Kong written by B. C. Seemann was published， in which 773 species were recorded （Seemann， 1857）. In 1861， Flora Hongkongensis， the first flora of Hong Kong written by George Bentham was published， and 1 056 taxa of vascular plants were included （Bentham， 1861）. Although a number of botanists including Prof. Hu Shiu Ying collected specimens for decades after World War ?ò， the flora remained largely under??explored. Prof. Xing Fuwu collected 3 500 specimens from 1996 to 1998 and together with the previously collected voucher specimens， and identified 1 884 species of native seed plants， belonging to 876 genera， of which 106 species were new records for Hong Kong （Xing et al， 1999）. In 2011， AFCD （Agriculture， Fisheries and Conservation Department， Hong Kong SAR， China， 2017） published the Flora of Hong Kong in four volumes. According to the latest Check List of Hong Kong Plants， the number of native vascular plants species and varieties has increased to 2 175 （Hong Kong Herbarium， Hong Kong SAR， China， 2012）.
Meanwhile， species new to science are still being described， for example， Syzygium impressum （Xia et al， 2008）， Carpinus insularis （Tong et al， 2014）， Gastrochilus kadooriei （Kumar et al， 2014）， Thismia hongkongensis （Mar & Saunders， 2015）， and new records （e. g. Yan et al， 2006； Gale et al， 2013 ） are continuously being reported.
During recent plant exploration trips in remote parts of Hong Kong， we found ten newly recorded taxa， three newly recorded genera to this region. The voucher specimens are deposited in Kadoorie Farm & Botanic Garden Herbarium （KFBG）. This article aims to report these discoveries.
1 Pteridaceae
Haplopteris elongata （Swartz ） E. H. Crane （Fig. 1： A）
In Syst. Bot. 22： 514.1998； FRPS， 3（2）： 25， pl. 7： 1： 4； FOC， 2-3： 255. ??Vittaria elongata Sw. In Syn. Fil. 109， 302. 1806.
Distribution： China （Fujian， Guangdong， Guangxi， Hainan， Hong Kong， Taiwan， Tibet， Yunnan）， Australia， Indonesia， Japan， Laos， Madagascar， Malaysia， Myanmar， Nepal， Philippines， Sri Lanka， Thailand and Vietnam. Ecology： Epiphytic on tree trunks or growing on the shady and moist side of rocks， shade tolerant.
Specimens seen： China. Hong Kong， New Territories， Ma On Shan， Luk Chau Shan， on the moist side of rocks， alt. 403 m， 4 March 2017， （Liu Jingang， JG0212， KFBG）.
Notes： Fern， epiphytic or epilithic. Rhizome long， creeping. Fronds clustered， drooping； lamina leathery， ribbon??like， up to 1 m long. Soral line marginal， immersed in deep groove， open outward.
It differs from Haplopteris flexuosa （F¨?e） E. H. Crane by having much longer lamina， and marginal soral line immersed in groove. H. flexuosa has been recorded as early as 1912 in Hong Kong and is common， while H. elongata is rare. We only found about ten small clumps scattered among the Luk Chau Shan rock jungle， growing with Asplenium crinicaule Hance.
2 Araceae
2. 1 Amydrium sinense （Engl.） H. Li. （Fig. 1： B）
In FRPS， 13（2）： 23， pl. 4： 8-10. 1979； FOC， 23： 10， 2010； ?? Scindapsus sinensis Engl. in Engl.， Bot. Jahrb. 29： 234. 1900.
Distribution： China （Hubei， Hunan， Hong Kong， Guangxi， Guangdong， Guizhou， Sichuan， Yunnan）， Vietnam.
Ecology：Growing upon or attached to trees or rocks， shade tolerant. Flowering in June-July， fruiting in July-November.
Specimens seen： China. Hong Kong， New Territories， Tai Po， Ng Tung Chai， next to the Main Fall， alt. 472 m， 14 July 2017， （Zhang Jinlong & Zhu Huiling etc， JL1194， KFBG）.
Notes： Herbaceous liana. Stem slender， climbing on rocks through fleshy aerial roots. Leaves distantly arranged， falcate??lanceolate， 13-2 ?? 5-8 cm， base subrounded， margin entire， apex acute； adaxially bright green， abaxially yellowish green. Petiole base sheathing.
Amydrium is a newly recorded genus to Hong Kong. There are five species in this genus， in which two have been found in South China. A. hainanense， another species reported from South China， differs from this species in having round to oval perforations on both sides along the midrib.
2. 2 Pothos repens （Lour.） Druce （Fig. 1： C）
In Rept. Bot. Exch. Club. Brit. Isles. 4： 641. 1917； FRPS， 13（2）： 20， pl. 3： 9. 1979； FOC， 23： 8， 2010； FGD， 9： 180， 2009； FHN， 4： 130， fig. 1034， 1977.
Distribution： China （Guangdong， Guangxi， Hainan， Hong Kong， Yunnan）， Laos， Vietnam.
Ecology： Climbing on trees or creeping over rocks in moist forests. Flowering in March-April， fruiting in May-July.
Specimens seen： China. Hong Kong， New Territories， Lantau Island， Tai O， alt. 38 m （7 September 2017， Craig Williams， CW0530， KFBG）. Notes： Epiphytic lianas， more than 10 m long. Stem angulate. Phyllode ca. 13-15 cm ?? 1 cm； leaf blade lanceolate， 3-5 cm ?? 1 cm； primary veins parallel. Leaves on young shoots much smaller， petioles elliptical. Spadix cylindric. This species differs from Pothos chinensis （Raf.） Merr. in having a much longer phyllode， which is 3-4 times longer than leaf blade.
3 Menispermaceae
Cyclea sutchuenensis Gagnep. （Fig. 1： D， E， F）
In Bull. Soc. Bot. France 55： 37， 1908； Diels in Engler， Pflanzenreich IV. 94： 319， 1910； FRPS 30（1）： 75， pl. 16： 6-11， 1996； FOC 7： 28， 2008； FGD 1： 45， fig. 45， 1987.
Distribution：China （Guangdong， Guangxi， Guizhou， Hong Kong， Hubei， Hunan， Sichuan， Yunnan）.
Ecology： Forests， forest margins， shrublands. Flowering in early summer and fruiting in autumn.
Specimens seen： China. Hong Kong， New Territories， Lantau Island， Wong Lung Hang Country Trail， alt. 604 m， （10 January 2017， Zhang Jinlong & Zhu Huiling， JL1085， KFBG）； the same location， （11 May 2017， Liu Jingang， JG0293， KFBG）.
Notes： Vines， glabrous， sometimes bracts pubescent， leaf blade lanceolate， 5-15 ?? 2-5.5 cm， thinly leathery or papery， with 3-5 palmate veines， base rounded. Male flowers： sepals 4 or 5， connate at base. This species differs from Cyclea hypoglauca （Schauer） Diels in having lanceolate leaf blades and a larger endocarp.
4 Fabaceae
Dumasia truncata Siebold & Zucc. （Fig. 1： G）
In Abh. Akad. Wiss. Monchen 4（2）： 119. 1843； FRPS 41： 253， 1995； FOC 10： 243， 2010；
Distribution： China （Anhui， Fujian， Taiwan， Guangdong， Guangxi， Henan， Hong Kong， Hunan， Hubei， Jiangxi， Shaanxi， Zhejiang）， Japan， Korea.
Ecology： Mountain slope， forest margins or streamsides， understorey. Flowering in August-September， fruiting in October-November.
Specimens seen： China. Hong Kong， New Territories， Tai Po， Ng Tung Chai， between the Main Fall and Scatter Fall， alt. 472 m （14 July 2017， Zhang Jinlong & Zhu Huiling etc.， JL1195， KFBG）
Notes： Perennial twining herbs， glabrous. The shape of leaflet is similar to Dumasia hirsuta， but the latter can be easily distinguished by hirsute stems and petioles （Pan & Zhu， 2010）. Only a very small population with less than five individuals along the hiking trail from Ng Tung Chai to Tai Mo Shan was observed. Dumasia is a newly recorded genus to Hong Kong.
5 Garryaceae
Aucuba obcordata （Rehder） Fu ex W. K. Hu et Soong. （Fig. 2： A） Checklist of Herbarium Specimens of Hubei. 166. 1964； Flora Sichuanica 1： 395. pl. 149： 6-8， 1981； FRPS， 56：19， 1990； FOC， 14： 226， 2005.
Distribution： China （Guangdong， Guangxi， Guizhou， Hong Kong， Hubei， Hunan， Shaanxi， Sichuan， Yunnan）.
Ecology： Forests， in shady and moist habitat. Flo??wering in March-April and fruiting in September-November.
Specimens seen： China. Hong Kong， New Territories， Tai Po， Tai Mo Shan， Tai Shing Stream， alt. 695 m. （21 January 2017， Hang Kingyeung， HKY0057， KFBG）.
Notes： Shrubs or small trees. Leaves obcordate or obovate， （4-） 8-14 ?? （2-） 4.5-8 cm， thickly papery to subleathery， base narrowly cuneate， margin coarsely dentate， sinuate between teeth， apex truncate orobcordate. This species could be easily distinguished from Aucuba chinensis Benth.， another species found in Hong Kong， by the shape of leaf apex.
6 Moraceae
6. 1 Ficus stenophylla Hemsl. （Fig. 2： B）
In Hook. Icon. Pl. 26： t. 2536. 1897. FHN， 2： 397. 1965； FGD， 1：207， fig. 234， 1987； FRPS， 23（1）： 151， pl. 37： 1-4 1998； FOC， 5： 58， 2003.
Distribution： China （Fujian， Taiwan， Guangdong， Guangxi， Guizhou， Hainan， Hong Kong， Hubei， Hunan， Jiangxi， Yunnan， Zhejiang）， Laos， Thailand， Vietnam.
Ecology： Forest， valleys. Flowering and fruiting in May-January of the following year.
Specimens seen： China. Hong Kong， New Territories， Wang Shan Keuk Ha Tsuen to Luk Keng， alt.
258.5 m， （6 December 2016， Zhang Jinlong， JL0990， KFBG）； Hong Kong， Mount Parker， 365 m， （14 December 2016， Liu Jingang， JG0454， KFBG）； Hong Kong， Mount Parker， （2 September 2008， Y. W. Lam， HK0043963， HK）.
Notes： Shrubs. This species is similar to Ficus variolosa Lindl. ex Benth.， but differs in having thin papery leaves and the blades are usually much narrower.
6. 2 Ficus gasparriniana var. esquirolii （H. L¨?v. & Vaniot） Corner （Fig. 2： C）
In Gard. Bull. Sing. 17： 428， 1959； FRPS， 23（1）： 145， pl. 34： 6， 1998； FOC， 5：57， 2003.
Distribution： China （Guangdong， Guangxi， Guizhou，Hong Kong， Hunan， Jiangxi， Sichuan， Yunnan）.
Ecology： Along hiking trails in forest margin. Understorey or growing in shrubland on the mountain ridge. Flowering in May-July.
Specimens seen： China. Hong Kong， New Territories， Ma On Shan， Wong Chuk Yeung； Along MacLehose Trail Section IV， on forest margin， alt. 246 m. （22 September 2016， Zhang Jinlong， JL0707， KFBG）； Ma On Shan， Wong Chuk Yeung， （28 April 2005， P. Chow， HK0044009， HK）. Notes： Although this taxon has been identified as Ficus gasparriniana var. esquirolii， it is closer to the type specimen of F. cehengensis S. S. Chang （Cao Z.Y.， 766， PE00024116， PE00024117， PE）. We adopted the treatment of Flora of China， where Ficus cehengensis has been treated as a synonym of F. gasparriniana var. esquirolii. The fruits of our specimens are globose and tubercular. This variety is similar to F. stenophylla Hemsl.， but leaves are 3-4 times broader， fruits are tubercular and attached to the stem with relatively robust pedicel. In comparison， the exocarp of F. stenophylla is almost smooth. Further investigation might be needed to clarify the identity of this taxon.
7 Aquifoliaceae
Ilex ficifolia C. J. Tseng ex S. K. Chen et Y. X. Feng （Fig. 2： D）
In Acta Phytotax. Sin. 37 （2）： 143， 1999； FRPS， 45（2）：34， pl. 6： 6-9， 1999； FOC， 11：378， 2008； ?? Ilex ficifolia C. J. Tseng in J. Xiamen Univ. Nat. Sci. 9（4）： 306， f. 3， 1962.
Distribution： China （Fujian， Guangdong， Guangxi， Hong Kong， Hunan， Jiangxi， Zhejiang）.
Ecology： In woodland. Flowering in May-June， fruiting in September-November.
Specimens seen： China. Hong Kong， New Territories， Lantau Island， Ngong Ping 360 Rescue Trail， alt. 425 m. （13 October 2016， Zhang Jinlong， JL0764， KFBG）.
Notes： Trees or shrubs. Leaf blade elliptic or oblong-elliptic， glabrous， margin sparsely and inconspicuously serrulate. Peduncles longer than pedicels. This species is similar to Ilex suaveolens （H. L¨?v.） Loes.， but differs in having shorter peduncles and shiny leaves.
8 Asteraceae
Paraprenanthes sororia （Miq.） C. Shih. （Fig. 2： E， F， G）
In Acta Phytotax. Sin. 26： 422. 1988； FOC， 21： 228， 2011. ??Paraprenanthes pilipes （Migo） Shih in Act. Phytotax. Sin. 26： 424. 1988； FRPS， 80（1）： 181， 1997； ??Prenanthes pilipes （Migo） Y. R. Ling， FGD， 8： 266， 2007.
Distribution： China （Anhui， Chongqing， Fujian， Guangdong， Guangxi， Guizhou， Hainan， Hong Kong， Hubei， Hunan， Jiangsu， Jiangxi， Sichuan， Taiwan， Xizang， Yunnan， Zhejiang）， Japan， South Korea， Vietnam.
Ecology： Roadsides， mountain slopes， shrublands， valleys， understorey of forests. Flowering and fruiting in May-August.
Specimens seen： China. Hong Kong， New Territories， Tai Po， Tai Mo Shan， along the trail between Ng Tung Chai and the pavilion beside Tai Mo Shan Forest Track. In open habitat close to stream. （27 May 2017， Liu Jingang & Hang Kingyeung， JG0301， KFBG） Notes： This is the most widespread species in this genus. The specimen was identified as Paraprenanthes pilipes by fo??llowing the keys in FRPS， but P. pilipes has been treated as a synonym of P. sororia in Flora of China. Only a small population was observed on Tai Mo Shan. Paraprenanthes is a newly recorded genus to HK.
Acknowledgements We are thankful to Stephan GALE， Craig WILLIAMS， Mandy WONG and WONG Shan for the assistance in collecting herbarium specimens. We thank PANG Kuen Shum （HK）， Rachel CHEUNG （HK） and ZENG Feiyan （SCIB） for kindly helping during specimen examination. FUNG Ka Yan and WONG Sai Fong （KFBG） for processing the herbarium specimens， and TAN Yunhong （HITBC）， JIANG Kaiwen， TU Tieyao （SCIB）， HU Aiqun （HKU）， PENG Hua （KUN） for helpful discussions. This study was sponsored by Kadoorie Farm and Botanic Garden.
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