Four new species of Begonia (Begoniaceae) from Vietnam: B. abbreviata, B. calciphila, B. sphenantheroides and B. tamdaoensis

Begonia abbreviata C.-I Peng, sp. nov. (sect. Petermannia)

Type:

VIETNAM. Quang Tri Province, Dakrong District, Trieu Nguyen Commune. Sterile plants collected by Pi-Fong Lu on 4 Nov 2009; type specimen made from the collection cultivated in the experimental greenhouse, Academia Sinica, 3 July 2010, Peng 22355 (holotype: HAST 139792; isotypes: E, HN)
Ecology and distribution:—Endemic to northern Vietnam, Quang Tri Province

Etymology:

The specific epithet refers to the short peduncle in the new species.

Additional specimen examined:

VIETNAM. Thua Thien Hue Province, elev. 500-600 m. Under broad-leaved evergreen forest, on soil, wet place, very common, 7 June 2004, Nguyen Tien Hiep 5917 (HN).

Notes:

Begonia abbreviata appears to be allied to B. eberhardtii Gagnepain (1919: 198), which was known only from a single collection made about a century ago from Vietnam. Both species are members of sect. Petermannia with elongate rhizomes and lacking upright stems. However, they differ markedly in leaf shape. In B. abbreviata, leaves are broadly ovate with entire margin and an acute apex. By contrast, leaves of B. eberhardtii are ovate, with irregularly and coarsely dentate margin and an acuminate apex.

Begonia calciphila C.-I Peng, sp. nov. (sect. Coelocentrum)

Type:

VIETNAM. Ninh Binh Province, Nho Quan District, Cuc Phuong National Park, near Khu Thung Tam Park Center (previously Bong Village), 20°21’01”N, 105°35’38”E, elev. ca. 400 m. On surface of steep limestone rocky slope in broadleaf forest, semishaded, occasional. Sterile plants collected on 18 Nov 2004; type specimen (with flowers) pressed from plants cultivated in the experimental greenhouse, 16 Feb 2011. Ching-I Peng, Wai-Chao Leong, Shin-Ming Ku, Nguyen Tien Hiep & Mai Van Sinh 20226 (holotype: HAST 139793; isotypes: A, CAS, E, K, KEP, HN, MO, P). Begonia semicava Irmsch., in sched.

Ecology and distribution:

Endemic to limestone karst areas in Cuc Phuong National Park, Ninh Binh Province, Vietnam, elev. 320-400 m. It grows on steep rocky slope surface or rock crevices in semishaded or shady broad-leaved forest.

Etymology:

The epithet 'calciphila' refers to the new species’ definite preference to limestone substrate. Although the name ‘Begonia semicava Irmsch.' has appeared on some specimens in Vietnamese herbaria (CPNP, HNu) and checklists (Frontier Vietnam 1994, 2002; Ho 1991), it was based on unpublished annotations by the late Dr. Edgar Imscher. This unpublished name has been excluded from the checklist of Southeast Asian Begonia (Hughes 2008).

Additional specimen examined:

VIETNAM. Ninh Binh Province, Cuc Phuong National Park, collected on limestone mountain, Oct 1964, Ngoc Bich s. n. (HNU); Bong, Cuc Phuong National Park. 1 December 1969, Nguyen Huu Hien B442 (CPNP); Ninh Binh Province, Nho Quan District, Cuc Phuong National Park, CP117. Hill southwest of helipad, primary forest on limestone slope, growing on rock crevice under dark forest floor, common, elev. 320-405 m, 20°21'00"N, 105°36'00"E, 18 November, 1999. D.D. Soejarto, N.T Hiep, N.M. Cuong, N.Q. Binh, N.X. Tam and M.VXinh 11012 (CPNP); Ninh Binh Province, Cuc Phuong National Park, CP213. Dan village, limestone mountain near ranger station, in primary forest, elev. 350 m, 20°18'97"N, 105°37'75"E, 14 August 2000, N.M. Cuong, D.T. Kien andM.V Sinh 961 (CPNP); Ninh Binh Province, Cuc Phuong National Park, CP2000. Near Bong, crowded in the herbaceous storey under evergreen broad-leaved forest, creeping herb 20 m long, 20°21'05"N, 105°35'83"E, 13 November, 2000, N.T. Hiep 4231 (CPNP).

Notes:

Begonia calciphila shares the long creeping habit with B. auritistipula Y.M. Shui & W.H. Chen (2005: 357), a calciphyte in southwestern Guangxi, China. The new species however differs from the latter in the petioles 2-10 cm long (vs. 9-22 cm); leaves orbicular-ovate with an acuminate apex (vs. ovate with an acute apex); leaf adaxial surface scabrous (vs. rugose and setulose); stipules villous (vs. glabrous); and petioles villous (vs. retrorsely hirsute).

Begonia sphenantheroides C.-I Peng, sp. nov. (sect. Platycentrum)

Type:

VIETNAM. Ha Giang Province, Yen Minh District, Du Gia Community, Lung Dam Village, 22°53’59’’N, 105°14’24’’E, elev. 780 m. On rock on N-facing mossy rocky slope above a running stream, semishaded to shaded, moist, mountain slope in broadleaf forest, occasional. Living collection made on 16 Nov 2004; type specimens pressed from plants cultivated in experimental greenhouse, Academia Sinica on 13 Sep 2012. Ching-IPeng 20216, with Wai-Chao Leong, Shin-Ming Ku, Nguyen Tien Hiep, Pham Van The & Nguyen Xuan Tam (holotype: HAST 139794; isotypes: A, E, HN, MO).

Ecology and distribution:

Begonia sphenantheroides C.-I Peng is distributed in limestone areas in Ha Giang Province and Tuyen Quang Province, northeastern Vietnam (Fig. 3). This species grow on semishaded to shady, moist, mossy rocky slopes in broadleafed forest.
Etymology:—The specific epithet refers to its resemblance to some members of Begonia sect. Sphenanthera in bearing stout rhizomes, upright stems and short, axillary, protandrous inflorescences.

Additional specimens examined:

VIETNAM. Tuyen Quang Province, Na Hang Distrct, Xuan Tan Community, Cai village, elev. 124 m, 10 Jan 2007, NQH 316 (HN).

Notes:

Begonia sphenantheroides is assignable to section Platycentrum. It bears a superficial resemblance to B. roxburghii A. DC. (section Sphenanthera) in the erect and branched stems, differing by being monoecious (vs. dioecious) and the broadly ovate leaf blade (vs. triangular-ovate), carpellate flower with 5 tepals (vs. 4 or rarely 3), abaxially scabrous (vs. glabrous) tepals, 2-styled pistil (vs. 4-styled), 2-locular ovary (vs. 4-locular), setose capsule (vs. glabrous or puberulent) and unequally 3-winged (vs. wingless, 4-horned) capsule. Most members of section Platycentrum are rhizomatous or with short aerial stems that appear only at anthesis. Begonia sphenantheroides has upright stems all year-round, a feature not frequently encountered in sect. Platycentrum. In the greenhouse, we observed some abnormally developed tubular pistillate flowers (Fig. 9:M) like those of sect. Symbegonia (Warb. 1894: 149) L. L. Forrest & P. M. Hollingsworth (2003: 208), which was probably induced by the cultivated condition.

Begonia tamdaoensis C.-I Peng, sp. nov. (sect. Platycentrum)

Type:

VIETNAM. Vinh Phuc Province, Tam Dao District. On rock surface along roadside slope, in broadleaf forest, elev. 1050 m, common locally. Living collection made on 21 Mar 1997; type specimens (in flower) pressed from plants cultivated in experimental greenhouse, 25 Oct 2002, Ching-IPeng 16634 (holotype: HAST 139795; isotype: A, E, HN, K, KEP, MO, P).

Ecology & Distribution:

Known only from Tam Dao, Vinh Phuc Province, Vietnam (Fig. 3). On rock face on roadside slope, in broadleaf forest, elev. 1050 m, locally common.

Etymology:

The specific epithet refers to the type locality, Tam Dao.

Additional specimen examined:

VIETNAM. Vinh Phuc Province, Tam Dao District. On rock face along roadside slope, in broadleaf forest, elev. 1050 m, common locally, 21 Mar 1997, Ching-I Peng 16634 (HAST); Vinh Phuc Province, Tam Dao District. Near base of rocky slope, elev. ca. 1000 m. Living collection made on 22 Mar 1997, specimens pressed from plant cultivated in experimental greenhouse, 29 Oct 2007, Ching-I Peng 16638 (HAST); Approximately 100 km NNW of Hanoi, Tam Dao Forest Reserve, on trail approximately 0.5 km S of bridge over Suoi B’ac River. Along trail on rocky soil, 21°27’09”N, 105°39’09”E, elev. 990 m. 9 Sep 1993. D. K. Harder et al. 1805 (HAST); Vinh Phuc Province, Tam Dao National Park, 6 Nov 2009, Pi-Fong Lu s. n., specimens pressed from plant cultivated in experimental greenhouse, 15 May 2015, Ching-I Peng 22285 (HAST).

Notes:

Begonia tamdaoensis is assignable to sect. Platycentrum by being rhizomatous, protandrous, staminate flowers basal and pistillate flowers distal, ovaries 2-locular and placentas with two branches, capsules pendulous, 2-loculate and wings very unequal (Doorenbos et al. 1998). The capsules are recurved, which is likely an adaptation for rain splash dispersal (Tebbit et al. 2006). However, it is unusual in having 3-styled carpellate flowers. Begonia versicolor Irmscher (1939: 546) is the only other species in sect. Platycentrum that is known to have 3-styled carpellate flowers and 2-loculed ovaries (Shui et al. 2002; Gu et al. 2007).

Begonia tamdaoensis resembles B. oreodoxa Chun & F. Chun ex C.Y. Wu & T.C. Ku (1995: 274) in SE Yunnan (China) and northern Vietnam in aspect and being very pubescent, but is distinguished by the very shallowly cordate leaves (vs. cordate), bracts fimbriate (vs. incised), carpellate flower with 5 tepals (vs. 4 or rarely 3) and 3 styles (vs. 2), placentas axile throughout (vs. axile for the most part, but parietal near summit of ovary).

References

Averyanov, L.V. & Nguyen, H.Q. (2012) Eleven new species of Begonia L. (Begoniaceae) from Laos and Vietnam. Turczaninowia 15 (2): 5-323.

Candolle, A. de (1859) Mémoire sur la famille des Bégoniacées. [ser. 4.] Annales des Sciences Naturelles; Botanique 11: 93-149. Candolle, A. de (1864) Prodromus Systematis Naturalis Regni Vegetabilis (DC.). Sumptibus Sociorum Treuttel et Würtz, Paris, 522 pp.

Doorenbos, J., Sosef, M.S.M. & Wilde, J.J.F.E. de (1998) The sections of Begonia including descriptions, keys, and species lists (Studies in Begoniaceae VI). Wageningen Agricultural University Papers 98 (2): 1-266.

Forrest, L.L. & Hollingsworth, P.M. (2003) A recircumscription of Begonia based on nuclear ribosomal sequences. Plant Systematics and Evolution 241 (3-4): 193-211. http://dx.doi.org/10.1007/s00606-002-0033-y Frontier Vietnam (1994) Tam Dao Nature Reserve: Results of a Biological Survey. Frontier Vietnam Environmental Research Report 1.

Society for Environmental Exploration, UK and Xuan Mai Forestry College, Hanoi, 82 pp.

Frontier Vietnam (2002) Huu Lien Nature Reserve: Biodiversity Survey and Conservation Evaluation 2000. Frontier Vietnam Environmental Research Report 21. Society for Environmental Exploration, UK and Institute of Ecology and Biological Resources, Hanoi, 53 pp. Gagnepain, M.F. (1919) Nouveaux Begonia d'Asie. Quelques synonymes. Bulletin du Muséum National d’Histoire Naturelle 25: 194-201. Gu, C.-Z., Peng, C.-I & Turland, N.J. (2007) Begoniaceae. In: Wu, Z.-Y., Raven, P. & Hong, D.-Y. (Eds.) Flora of China, vol 13. Science Press, Beijing & Missouri Botanical Garden Press, St. Louis, pp. 153-207.

Ho, P.H. (1991) Begoniaceae. In: Ho, P.H. (Ed.) Cayco Vietnam, An Illustrated Flora of Vietnam, v.1. Tre Publishing House, Vietnam, pp. 728-743.

Huang, S.-H. & Shui, Y-M. (1994) New taxa of Begonia from Yunnan. Acta Botanica Yunnanica 16 (4): 333-342.

Hughes, M. (2008) An annotated checklist of Southeast Asian Begonia. Royal Botanic Garden Edinburgh, Edinburgh, 164 pp.

Irmscher, E. (1929) Die Begoniaceen der Malaiischen Halbinsel. Mitteilungen aus dem Institut für allgemeine Botanik in Hamburg 8: 86-160.

Irmscher, E. (1939) Die Begoniaceen Chinas und ihre Bedeutung für die Frage der Formbildung in polymorphen Sippen. Mitteilungen aus dem Institut für Allgemeine Botanik in Hamburg 10: 431-557.

Klotzsch, J.F. (1854) Begoniaceen-Gattungen und Arten. Abhandlungen der Königlischen Akadamie der Wissenschaften Berlin, 135 pp. + 12 pls.

Legro, R.A.H. & Doorenbos,J. (1969) Chromosome numbers in Begonia 1. Netherlands Journal of Agricultural Science 17:   189-202.

Legro, R.A.H. & Doorenbos, J. (1971) Chromosome numbers in Begonia 2. Netherlands Journal of Agricultural Science 19:   176-183.

Legro, R.A.H. & Doorenbos,J. (1973) Chromosome numbers in Begonia 3. Netherlands Journal of Agricultural Science 21:   167-170.

Levan, A., Fredga, K. & Sandberg, A.A. (1964) Nomenclature for centromeric position on chromosomes. Hereditas 52: 201-220. http://dx.doi.org/10.1111/j.1601-5223.1964.tb01953.x Linnaeus, C. (1753) Species Plantarum. Imprensis Laurentii Salvii, Homiae, 1200 pp.

Miquel, F.A.W. (1856) Flora van Nederlandsch Indië. C. G. van der Post, Amsterdam, 1116 pp., +14 pls.

Nguyen, Q.H., Peng, C.-I. & Ku, S.-M. (2010) Begonia vietnamensis, an attractive new species with peltate leaves from Vietnam. Begonian 77: 18-21.

Nakata, M., Guan, K.Y, Li, J.X., Lu, YX. & Li, H.Z. (2007) Cytotaxonomy of Begonia rubropunctata and B. purpureofolia (Begoniaceae). Botanical Journal of the Linnean Society 155: 513-517. http://dx.doi.org/10.1111/j.1095-8339.2007.00724.x Peng, C.-I., Ku, S.-M., Kono, Y & Liu, Y (2012) Begonia chongzuoensis (sect. Coelocentrum, Begoniaceae), a new calciphile from Guangxi, China. Botanical Studies 53: 285-292.

Peng, C.-I., Yang, H.-A., Kono, Y., Chung, K.-F., Huang, Y-S., Wu, W.-H. & Liu, Y. (2013) Novelties in Begonia sect. Coelocentrum: B. longgangensis and B. ferox from limestone areas in Guangxi, China. Botanical Studies 54: e44. http://dx.doi.org/10.1186/1999-3110-54-44 Peng, C.-I., Ku, S.-M., Yang, H.-A., Leong, W.-C., Liu, Y, Nguyen, T.H., Yoshiko, K. & Chung, K.-F. (2014a) Two new species of Begonia sect. Coelocentrum, B. guixiensis and B. longa, from Sino-Vietnamese limestone karsts. Botanical Studies 55: e52. http://dx.doi.org/10.1186/s40529-014-0052-8 Peng, C.-I., Wang, H., Kono, Y. & Yang, H.-A. (2014b) Begonia wui-senioris (sect. Platycentrum, Begoniaceae), a new species from Myanmar. Botanical Studies 55: e13. http://dx.doi.org/10.1186/1999-3110-55-13 Peng, C.-I., Lin, C.-W., Yang, H.-A., Kono, Y & Nguyen, H.Q. (2015) Six new species of Begonia (Begoniaceae) from limestone areas in Northern Vietnam. Botanical Studies 56: e9. http://dx.doi.org/10.1186/s40529-015-0089-3 Shui, Y-M. & Chen, W.-H. (2005) New Data of Sect. Coelocentrum (Begonia) in Begoniaceae. Acta Botanica Yunnanica 27 (4): 355-374. Shui, Y-M., Peng, C.-I & Wu, C.-Y (2002) Synopsis of the Chinese species of Begonia (Begoniaceae), with a reappraisal of sectional delimitation. Botanical Bulletin of Academia Sinica 43: 313-327.

Smith, J.J. (1906) Begonia bipinnatifida n. sp. Bulletin du Département de l’Agriculture aux Indes Néerlandaises 2: 47-48.

Tebbitt, M.C., Lowe-Forrest, L., Santoriello, A., Clement, W.L. & Swensen, S.M. (2006) Phylogenetic relationships of Asian Begonia, with an emphasis on the evolution of rain-ballist and animal dispersal mechanisms in sections Platycentrum, Sphenanthera and

Leprosae. Systematic Botany 31: 327-336. http://dx.doi.org/10.1600/036364406777585784 Wu, C.-Y. & Ku, T.-C. (1995) New Taxa of the Begonia L. (Begoniaceae) from China. Acta Phytotaxonomica Sinica 33 (3): 251-280.

 

CHING-I PENG, HSUN-AN YANG, YOSHIKO KONO,
1Herbarium (HAST), Biodiversity Research Center, Academia Sinica, Nangang, Taipei 115, Taiwan

MING-JER JUNG
3rd Floor, No. 27, Lane 13, Ching-Hua St., Wenshan District, Taipei City, Taiwan

TIEN HIEP NGUYEN
Center for Plant Conservation (CPC), Vietnam Union of Science and Technology Associations, M 25/32, Lane 191, Lạc Long Quân Rd,Nghia Dô, Ha Noi, Cau Giay District, Vietnam