| Summary: | 碩士 === 東海大學 === 生命科學系 === 98 === There are approximately 120 species in the genus Mussaenda L. (Rubiaceae) widely distributed in tropical Asia, Africa and Pacific Islands. This genus is dioecious, heterostyles, and most species of this genus with enlarged white calyxes (also known as the petaloid). There are 2 species of Mussaenda recorded in Flora of Taiwan Vol.4 2nd (ed.): Mussaenda macrophylla Wall. and M. pubescens W.T. Aiton (Yang, 1998). The former one is distributed in Lanyu Island only and China, and the latter one is found throughout the entire island of Taiwan and off-shore islands. During collecting samples in the field and comparing specimens of both species in the different herbaria of Taiwan, China, Japan and Europe, there have been some questions raised regarding the classification of this genus. After review in published papers and comparison of type specimens led to the conclusion that population of M. macrophylla collected from Lanyu Island has some characters which differ from the type specimen of M. macrophylla collected from Nepal. Moreover, the M. pubescens complex in Taiwan has numerous variations and it should be separated into different taxon. The results show that flora organs are a suitable taxonomic trait to classify this complex. The morphological and palynology pollen traits were compared, and the Scanning Electron Microscope (SEM) was used to observe the leaf and seed surfaces for completion of the taxonomic revision. On the other hand, after reviewing published papers of synonym and comparing type specimen or specimens in the neighborhood area, it is concluded that M. pubescens complex could be separated into five taxa: 1. Mussaenda parviflora Miq. is the same species in Japan. 2. Mussaenda taihokuensis Masam. is differ from M. parviflora with its’ beige color of corolla tube. 3. Mussaenda taiwaniana Kaneh. is differ from M. parviflora with its’ board leaves and habitat. 4. Mussaenda albiflora Hayata treated as the synonym of M. pubescens, which distributed in Hong Kong and China. 5. The taxon, Mussaenda pubescens used in Flora of Taiwan 2nd (ed.) raise into a new combination name i.e. M.formosanum (Matsum.) T.Y. Aleck Yang & K.C. Huang with its’ inflorescence cymes. Furthermore, Mussaenda macrophylla in Lanyu island should be restored to an endemic species i.e. M. kotoensis Hayata with its’ habitat is small tree and small calyx.
Phylogenetic analyses were conducted based on nrITS and trnT-trnF region in chloroplasts. The results show that Mussaenda kotoensis are grouped in one clade, M. taiwaniana are grouped with M. shikokiana and others individuals are grouped with M. pubescens and M. parviflora. Combining these results, there are six taxa of Mussaenda in Taiwan.
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