Camellia langbianensis (Gagnep.) P.H. Ho , Cayco Vietnam 1(1): 537. 1991.

Zhao, Dongwei, 2023, Taxonomic revision of Camellia langbianensis (Theaceae) with four new synonyms, PhytoKeys 234, pp. 275-281 : 275

Camellia langbianensis (Gagnep.) P.H. Ho, Cayco Vietnam 1(1): 537. 1991.

Dankia langbianensis ≡ Dankia langbianensis Gagnep., Fl. Indo-Chine [P.H. Lecomte et al.] Suppl.: 198. 1939. Lectotype (designated by Zhao et al. [2017a: 173]): Vietnam. [Lam Dong]: entre B. dlé et Dankia , Langbiang, 1200-1300 m elev., 26 October 1930, E. Poilane 18648 (P00754831! Image: https://science.mnhn.fr/institution/mnhn/collection/p/item/p00754831).

Camellia vidalii = Camellia vidalii Rosmann, Adansonia 21(2): 319. 1999. Holotype: Vietnam. Lam Dong: Bao Loc, 875 m elev., December 1998, J.C. Rosmann et al. 981 (P00834283! Image: https://science.mnhn.fr/institution/mnhn/collection/p/item/p00834283).

Camellia dongnaiensis = Camellia dongnaiensis Orel, Novon 16(2): 244. 2006. Syn. nov. Holotype: Vietnam. Lam Dong: unnamed tributary, the headwaters of Dong Nai River, 17 January 2004, G. Orel et al. 21148 (NSW868472, image!).

Camellia oconoriana = Camellia oconoriana Orel, Curry & Luu, Edinburgh J. Bot. 70(3): 440. 2013. Syn. nov. Holotype: Vietnam. Lam Dong: unnamed mountain about 120 km SW of Dalat, 22 November 2010, G. Orel & A.S. Curry 0720 (NSW900415, image!).

Camellia decora = Camellia decora Orel, Curry & Luu, Pursuit Hidden Camellias Vietnam China 173. 2015. Syn. nov. Holotype: Vietnam. Ninh Thuan, 23 March 2009, H.T. Luu et al. VNM 12381 (NSW901588, image!).

Camellia tadungensis = Camellia tadungensis Orel, Curry & Luu, Pursuit Hidden Camellias Vietnam China 256. 2015. Syn. nov. Holotype: Vietnam. Dak Nong: Ta Dung Nature Reserve, 11 January 2011, H.T. Luu et al. TD 264 (NSW901888, image!).

Description.

Shrubs 4-6 m tall. New branchlets puberulous; terminal buds pubescent. Petioles 6-17 mm long, puberulous to glabrous; leaf blades narrowly elliptic, oblong or ligulate, 15-40 × 2.5-15 cm, coriaceous, abaxially yellowish or pale green and puberulous, adaxially dark green and glabrous, mid-rib raised on both surfaces, secondary veins 14-27 on each side of mid-rib, abaxially raised and adaxially impressed, base cuneate, obtuse, rounded or subcordate, margin nearly entire or sparsely serrulate, apex attenuate. Flowers solitary or paired, borne in the axils of leaves or on short bracteate shoots; short shoots bearing 3-5 bracts subtending flowers; bracts caducous; flowers 2.5-4.5 cm in diam. Pedicels 2-5.5 cm long, puberulous to glabrous. Bracteoles 2-4, alternate, narrowly ovate or deltate, 1.5-6 × 1.5-3 mm, outside puberulous, inside glabrous or puberulous, margin ciliolate. Sepals 5-6, broadly ovate or ovate, 4-7 × 4-12 mm, outside puberulous to pubescent, inside glabrous or puberulous, margin ciliolate. Petals 7-9 in 2 whorls, yellow or with pale red fringe, broadly obovate or elliptic, 1-2.5 × 1-2.2 cm, outer surface pubescent to puberulous, inner surface glabrous or puberulous. Stamens 1-2 cm long, outer filaments basally connate for 3-4 mm, adnate to petals for 1-2 mm, glabrous or basally pubescent. Ovary oblate or ovoid, densely pubescent. Styles 3-6, distinct, 1-2.5 cm long, pubescent or gradually becoming glabrous apically. Capsule oblate, 5-7 cm in diam., 2-3.5 cm in height; pericarp 0.5-3 mm thick. Seeds reddish-brown or black, hemispherical or polyhedral, 1.5-2 cm in diam., glabrous and shiny.

Phenology.

Flowering November-April, fruiting April-October.

Distribution.

Endemic to southern Vietnam, in Dak Nong, Khanh Hoa, Lam Dong and Ninh Thuan Provinces (Fig. 1 ).

Habitat.

Evergreen forest, 750-1800 m elev.

Additional specimens examined.

Vietnam. Khanh Hoa: Cam Lam, Hon Ba , 8 April 2012, L.H. Truong & T. Gioi KH 86, KH 87 & KH 88 (SGN), 8 April 2013, L.H. Truong & T. Gioi KH 1140 (SGN) . Lam Dong: Bao Loc, Pu Sapoum près Mt. ageicole de Blao, 1000-1100 m elev., 10 January 1934, E. Poilane 23790 (P04500357, image: https://science.mnhn.fr/institution/mnhn/collection/p/item/p04500357); Dam Ri , 11 January 2012, DL 12.01.02 (DLU), 1 December 2012, DL 12.12.02 (DLU), 31 January 2015, DL 15.01.03 (DLU), 11°38'29"N, 107°44'25"E, 780-830 m elev., 30 November 2015, D.W. Zhao & L.V. Dung 124 (TCD), 125 (KUN, PHH, TCD) & 126 (TCD); Don Duong, Pro, 15 February 2014, DL 14.02.01, DL 14.02.02, DL 14.02.03 (DLU), DL 15.10.08 (DLU); massif du Braïan près de Djiling, 1700-1800 m elev., 17 January 1935, E. Poilane 23959 (P05312544, image: https://science.mnhn.fr/institution/mnhn/collection/p/item/p05312544), 1200-1400 m elev., 3 February 1935, E. Poilane 24105 (P06838121, image: https://science.mnhn.fr/institution/mnhn/collection/p/item/p06838121) . Ninh Thuan: Ninh Hai, Nui Chua, 22 March 2009, Truong & Dat NC 198 (SGN), March 2010, Luu 749 (SGN), March 2011, Luu 750 (SGN), 20 April 2012, Luu 736 (SGN); Ninh Son , Phuoc Binh , 37 km to NE from Dalat City , 12°6'N, 108°43'E, 1300-1400 m elev., 2 April 1997, L. Averyanov et al. VH 3561 (HN, P05191415, image: https://science.mnhn.fr/institution/mnhn/collection/p/item/p05191415; P05247468, image: https://science.mnhn.fr/institution/mnhn/collection/p/item/p05247468) .

Notes.

The diagnostic morphological differences amongst the type materials of C. decora , C. dongnaiensis , C. langbianensis , C. oconoriana , C. tadungensis and C. vidalii are shown in Table 1 . Quach et al. (2021) argued that C. vidalii could be distinguished from C. langbianensis by its glabrous pedicel, basal part of filaments, upper part of styles and inside surfaces of the bracteoles, sepals and petals, whereas the latter was hairy on the parts listed. However, the original materials of C. langbianensis bear a glabrous to sparsely puberulous pedicel and its bracteoles are glabrous or sparsely puberulous on the inside surface (isolectotypes: K000704329; P00754832, image: https://science.mnhn.fr/institution/mnhn/collection/p/item/p00754832). The specimens L. Averyanov et al. VH 3561 at HN and P, cited as C. langbianensis in Quach et al. (2021), bear nearly glabrous sepals and much less hairy petals. By contrast, the filaments of the holotype of C. vidalii , J.C. Rosmann 981 (P00834283), are basally pubescent. The persistent sepals of L.H. Truong & T. Gioi KH 1140 at SGN, a specimen that is conspecific with C. vidalii , are hairy on the inside surface.

When more collections are examined, it is hard to ignore the morphological variations of the plants represented by C. langbianensis and its synonyms listed above (Table 1 ). The size of leaves and indumenta of pedicel, sepals, petals and filaments usually vary continuously amongst individuals and a clearly diagnostic breaking point is generally absent. For example, the size of the leaves increases from the type of C. langbianensis to that of C. dongnaiensis , with those of C. decora , C. oconoriana , C. tadungensis and C. vidalii locating between them and overlapping with each other. The type of C. langbianensis might be much hairier on the sepals and petals than those of the synonyms recognised above (Table 1 ; Quach et al. [2021]). The morphological variation is, however, hardly convincing to differentiate species in Camellia because this kind of variation can also be found within other taxa, such as C. sinensis var. pubilimba Hung T. Chang and C. lanceolata (Blume) Seem. ( Ming 2000). Orel (2006) argued that C. dongnaiensis was unique by its yellow petals with pink margin; nevertheless, the fringed pink petals can also be found in C. langbianensis ( Quach et al. 2021). Therefore, I retain my previous treatment ( Zhao 2019) that C. vidalii is a heterotypic synonym of C. langbianensis before more data are available and treat C. decora , C. dongnaiensis , C. oconoriana and C. tadungensis as new heterotypic synonyms of C. langbianensis .

Camellia langbianensis is characterised by its generally large leaves, long pedicels, persistent bracteoles and sepals, yellow petals hairy outside, distinct styles, hairy ovaries and glabrous and shiny seeds (Table 1 ). As a member of sect. Camellia Piquetia (Pierre) Sealy, it is closely-related with C. dalatensis V.D. Luong, Ninh & Hakoda ( Tran et al. 2012) and C. piquetiana (Pierre) Sealy ( Zhao et al. 2023). Camellia langbianensis can be distinguished from C. dalatensis by its nearly glabrous branchlets, petiole and abaxial surface of the leaf blade, whereas the latter are pubescent on those parts mentioned. Camellia piquetiana bears a shorter pedicel and red petals, while C. langbianensis has a longer pedicel and yellow petals.

Figures

Figure 1. Geographic distribution of Camellia langbianensis (red triangle) in Vietnam.