Miscellany. Nine new yellow flowering Camellia (Theaceae) species from Viet Nam

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1 Miscellany 149 Nine new yellow flowering Camellia (Theaceae) species from Viet Nam George Orel & Anthony S. Curry Royal Botanic Gardens, Mrs Macquaries Road, Sydney, NSW 2000, Australia Abstract. Eighteen yellow flowering species of Camellia (Theaceae), nine of which are endemic to the southern provinces of Viet Nam, were compared with one another. Morphological data indicates a number of dissimilarities between some of the nine newly discovered Camellia species and the already known, yellow flowering taxa. Presented data supports the assertion that the members of genus Camellia are closely related however the newly found Vietnamese species exhibit a number of distinctive and primitive morphological traits. The newly acquired data suggests that southern Viet Nam is not only an important centre of genetic diversity but also a part of the postulated southern area of origin for genus Camellia. Key words: Camellia, Lam Dong, morphology, new species, taxonomy. Introduction Historically only a relatively small number of Camellia species were thought to be native to the southern mountain regions of Viet Nam. The so called Camellia Provinces of China and northern parts of Viet Nam, e.g. the Tam Dao, Ba Vi and Cuc Phuong National Parks and the adjacent geographical areas that are relatively close to the Chinese border, were traditionally considered to be the major centres of distribution for genus Camellia (Sealy, 1958; Chang & Bartholomew, 1984; Gao et al., 2005). Recent systematic exploration carried out on the Da Lat Plateau and the Lang Biang Massif in the southern provinces of Viet Nam has resulted in the discovery of a number of new Camellia taxa, some of which have already been published (Orel, 2006; Orel & Wilson, 2010a, Orel & Wilson 2010b, Orel et al, 2012). So far nine yellow flowering species have been found. These discoveries not only confirm the floristic richness of southern Viet Nam but also establish it as an important centre of Theaceae genetic diversity. South Viet Nam may also be the possible northern boundary of the hypothesised southern area of origin for genus Camellia (Orel & Marchant, 2006). The number of Camellia species recorded, nature of the species found, the possession of primitive characters by many of the Camellia species, and the degree of species endemism all appear to support this hypothesis. Materials and Methods Morphological characters of 18 yellow flowering species of Camellia were studied to determine the interspecific status of the nine newly discovered Camellia taxa from Viet Nam. All plant materials were collected from the wild and the exact provenance details for each species have been withheld for conservation reasons. General provenance and population data for all species used are presented in Table 1. Selected morphological data derived from observations of the nine newly discovered Camellia species and other nine yellow flowering Camellia from Viet Nam are presented in Table 2. The flower colour and the dominant morphological traits are presented. Some 30 multiple state characters were scored from in situ observations. The assessments of herbarium materials were assessed under laboratory conditions. The morphological matrix, where the absence of a character was denoted 0 and the presence of a character 1, 2, 3, 4, 5 and 6 was constructed and analysed (Fig. 1.). Phylip 3.69, a computational program for inferring evolutionary phylogenies was used to generate the taxonomic trees. Results See Fig. 1 and Fig. 2. Discussion Historically only a relatively small number of yellow flowering Camellia species were considered native to the southern provinces of Viet Nam. The northern parts of Viet Nam, e.g. the

2 150 Table 1. General provenance and population data for 18 yellow flowering Camellia species from Viet Nam and China used in this paper Taxon* Provenance Population Notes C. dongnaiensis* Viet Nam Less than 20 individual plants collected C. luteocerata* Viet Nam Small scattered population C. inusitata* Viet Nam Small relatively protected population C. sp. 0720** Viet Nam Relatively large, established population C. sp. 698** Viet Nam Small scattered population C. sp. OCa** Viet Nam Population size unknown C. sp. OCb** Viet Nam Population size unknown C. sp. OCc** Viet Nam Population size unknown C. sp. OCT5** Viet Nam Population size unknown C. gilbertii Viet Nam Recently discovered new population C. petelotii Viet Nam Population relatively large C. flava Viet Nam Population relatively large C. rosmanii Viet Nam Small population, some in cultivation C. aurea Viet Nam Population size unknown C. nitidissima Viet Nam In cultivation C. nitidissima var. microcarpa Viet Nam Taxonomic status uncertain C. luteoflora Viet Nam Population size unknown C. tunhingensis Viet Nam Population size unknown * Bold print denotes newly discovered Camellia species ** Species in the process of publication, accession numbers only Table 2. Morphological details for 9 newly discovered yellow flowering Camellia species from Viet Nam Taxon Flower colour Population Notes C. dongnaiensis* yellow-apricot, pink margins large leaves up to 60.0 cm long C. luteocerata* intense yellow flowers laterally oblongoid C. inusitata* light yellow lacks secondary branching C. sp. 0720** light to mid yellow, pink-lilac margins oblate fruit, 5.5 cm diam. C. sp. 698** dark yellow petals in spiral arrangement C. sp. OCT5** pale yellow inflorescence of flower buds C. sp. OCa** dark yellow crinkly, zigzag like styles C. sp. OCb** light yellow with pink blush filaments thickened at their base C. sp. OCc** light yellow outer filaments thin, inner wide, strap like * Newly discovered and described Camellia species ** Species in the process of publication, accession number only

3 151 Figure 1. Evolutionary phylogenies derived from the analyses of 30 multiple state characters of 18 yellow flowering Camellia species using Phylip 3.69 computational program C. dongnaiensis* C. gilbertii C. petelotii C. rosmannii C. aurea C. nitidissima C. nitidissima var. microcarpa C. sp. OCa* C. sp. OCc* C. sp. OCb* C. inusitata* C. flava C. tunghinensis C. sp. CT5* C. luteoflora C. sp. 0720* C. sp. 698* C. luteocerata* * Bold print indicates the newly discovered species

4 152 Tam Dao, Ba Vi and Cuc Phuong National Parks and their environs, as well as the geographical areas relatively close to the Chinese border, were traditionally considered to be the major centres of yellow Camellia distribution. This fact can be amply demonstrated by even a cursory look at the relevant literature. The total number of published, southern Vietnamese yellow flowering Camellia species is small and varies from author to author. It is also subject to issues surrounding the flower colour of herbarium specimens, e.g. of C. krempfii (Gagnep.) Sealy and C. dormoyana (Pierre ex Laness.), and inconsistencies present in published descriptors, e.g. C. gilbertii (A. Chev.) Sealy (Sealy, 1958; Chang & Bartholomew, 1984; Ho, 1991; Tran, 2002; Gao et al., 2005). The relatively recent exploration of the southern provinces of Viet Nam carried out by the Australian and Australian-Vietnamese scientific teams has resulted in the discovery of at least nine new yellow flowering Camellia species (Orel, 2006; Orel & Wilson, 2010a, Orel & Wilson 2010b, Orel et al, 2012). These, and numerous other Camellia and Theaceae, finds established southern Viet Nam as an important centre of genetic diversity and possibly part of the northern region of the postulated southern centre of origin for genus Camellia (Orel & Marchant, 2006). The discovery of more than 30 new Camellia species to date in this region places the geographical area of southern Viet Nam on par with other known global centres of biodiversity, e.g. the Western Ghats that hold about 30% of India s plant species (Bawa & Krishnaswami, 2007) and the state of Georgia in the USA, which also contains about 30% of all tree species of the USA and Canada (Brown & Kirkman, 1990). It is important to note, that the nine newly discovered Camellia species (Table 1.) possess a number of morphological characters that are quite dissimilar to many of other described yellow Camellia taxa (Table 2.). Some of these traits have not been observed in the morphologies of the known yellow Camellia species or Camellia species of other flower colours. For example, C. inusitata Orel, Curry & Luu lacks secondary branching, has a laterally compressed main trunk, especially at the tip, and a distichous leaf arrangement; C. sp. 698 possesses flowers with a spiral and not whorled Figure 2. Interspecific relationships derived from analyses of 30 multiple state characters for the nine newly discovered yellow flowering Camellia species using Phylip 3.69 computational program C. sp. OCb C. dongnaiensis C. sp. OCa C. sp. OCc C. inusitata C. sp. CT5 C. sp C. sp. 698 C. luteocerata

5 153 A F B G C H I D E A = C. inusitata B = C. sp. 698 C = C. sp. OCa D = C. sp. OCT5 E = C. sp F = C. sp. OCb G = C. sp. OCc H = C. dongnaiensis I = C. luteocerata.

6 154 petal arrangement; C. luteocerata also possesses a spiral petal arrangement and has oblongoid flowers; C. sp. CT5 has a large inflorescence composed of 12 to14 flower buds, and its flowers open in a predetermined sequence, from proximal to distal end; C. sp. OCa possesses crinkly, zigzag like styles; the flowers of C. sp. OCb are light yellow with pink mid petal blush and its filaments are also conspicuously thickened at their bases; C. sp. OCc possesses two types of filaments, the outer filaments are long and thin, while the inner filaments are wide and laterally flattened, i.e. strap like (Table 2.). Figure 1. affirms the long held view with regard to the morphological closeness of the member species, yellow or otherwise, of genus Camellia (Orel et al, 2003; Orel & Marchant 2006). Figure 1. also highlights the existence of morphological dissimilarities possessed by many of the recently collected, South Vietnamese, yellow flowering, Camellia taxa. A wealth of published, and soon to be published, data obtained from a number of morphological and molecular studies of nonyellow flowering Camellia species of southern Viet Nam, also confirms that many of these species also possess distinctive morphological traits (Orel 2006; Orel & Wilson 2010b; Orel & Wilson 2012). Available scientific data indicates that some of the Camellia taxa found on the Da Lat Plateau and the adjoining Lang Biang Massif are morphologically different when compared with other Camellia species. Additionally this suggests that these species must have been subjected to different environmental conditions than those experienced by North Vietnamese and the Chinese Camellia species. A separate evolutionary process, aided by the processes of natural selection, is thus implied. The abovementioned findings (Figure 1.) and the data presented in Figure 2. profoundly influence not only the general taxonomy of genus Camellia but also the taxonomy of the yellow flowering Camellia species. It became a necessity in response to these findings to widen the terms of taxonomic reference with regard to the genus Camellia. The establishment of a number of new sections has enabled the accommodation of the newly established species and their unique combinations of morphological characters within the existing taxonomies. Data for the yellow flowering Camellia species presented in Figure 1. and other soon to be published data do not appear to support or correlate with sect. Chrysantha Chang as published. A substantial number of morphological characters possessed by the newly discovered yellow Camellia species do not conform to the specific parameters on which sect. Chrysantha (sensu Chang & Bartholomew 1984). Consequently the establishment of sect. Chrysantha on the basis of the notion of systematic development routes of organ morphology, with reference to flower colour (Chang & Ye 1994) cannot be sustained. The question arising out of this research is: do the rather unorthodox morphological dissimilarities of the nine newly discovered species translate into a general genetic dissimilarity? This question can be answered in the affirmative. The phenotypic unorthodoxy is reflected in the respective Camellia genotypes. The attempts to directly sequence the ITS PCR product of the new Camellia species were only partially successful, even when using a number of previously tested, positive, result bearing primers. As this paper is only a preliminary study into the interspecific relationships of the southern Vietnamese yellow flowering species of Camellia, a larger study, that will eventually encompass all of the newly discovered Camellia species, is already in progress and will be published later. Literature cited Bawa, K.S., Das, A. & Krishnaswami, J Western Ghats and Sri Lanka Biodiversity Hotspot. Critical Ecosystem Partnership Fund Publication. Brown, C.L. & Kirkman, L.K Trees of Georgia and adjacent states. Portland Oregon: Timber Press. Chang, H.T. and Bartholomew, B Camellias. Timber Press, Portland, Oregon. Chang, H.T. & Ye, C Diagnosis of the systematic development of Theaceae. International Camellia Journal No. 26. Gao, J., Parks C.R. and Du, Y Collected species of the genus Camellia: An illustrated outline. Zhejiang Science and Technology Press, P.R. China.

7 Ho, P-H Cayco Viet Nam. Vol. 1. Part 1., Santa Ana, California, Mekong Printing. 155 Orel, G Notes on Camellia dongnaiensis a new species from Vietnam. International Camellia Journal 2006, No. 38: Orel, G., Marchant, A. D. & Richards, G. D Molecular genetic investigation into evolutionary relationships of yellow-flowered Camellia species from South-East Asia. Collected Papers, International Camellia Congress 2003, March 6-March 9, Jinhua City, P. R. China. Orel, G., Marchant, A. D Investigation into the evolutionary origins of Theaceae and genus Camellia. (Adapted from Melbourne Congress lecture) International Camellia Journal 2006, No. 38: Orel, G. & Wilson, P.G. 2010a. Camellia luteocerata sp. nov. and a new section of Camellia (Dalatia) from Vietnam. Nordic Journal of Botany 28: Orel, G. & Wilson, P. G. 2010b. A New Species of Camellia Sect. Stereocarpus (Theaceae) from Vietnam. - Novon 20: Orel, G. & Wilson, P. G. (2012) Camellia cattienensis: a new species of Camellia (sect. Archaecamellia: Theaceae) from Viet Nam. Kew Bulletin 66: Orel, G., Wilson, P. G., Curry, A. S. & Luu Hong Truong (2012). Camellia inusitata (Theaceae), a new species forming a new section (Bidoupia) from Vietnam. Edinburgh Journal of Botany 69: Sealy, J. R. (1958). A revision of the genus Camellia. Royal Horticultural Society. Tran, N Biodiversity of the genus Camellia of Viet Nam. Proceedings of the First National Symposium on yellow Camellias in Viet Nam. Tam Dao.