TAXONOMY ON THE GENUS COLONA CAV. (TILIACEAE Juss.) IN VIET NAM

Abstract

According to Tang Ya, Michael G. G. and Laurence J. D. (2007), the genus Colona Cav. had about 30 species in the world. There were 9 Colona species in Vietnam: Colona auriculata, C. evecta, C. evrardii, C. floribunda, C. kodap, C. nubla, C. poilanei, C. scabra, C. thorelii. They are mainly trees, rarely shrubs. They are mostly rare in the natural, among them C. poilanei, C. nubla, C. evrardii are recorded as endemic species. Almost of them were used as woody, three species are used as fibres from bark, one species as medicinal plants.

Genus Colona is in the  fruit having wing group with Berrya, Craigia, Excentrodendron but it differs on flowers bisexual, petal 5. To distinguish species in Colona genus base on important characteristics as stamens free (C. auriculata, C. evecta, C. evrardi, C. nubla, C. scabra) or connect into 5 fascicles at the base (C. floribunda, C. kodap, C. poilanei, C. thorelii); style with tomentosa at base (C. evecta, C. floribunda, C. kodap, C. nubra, C. poilanei, C. thorelii) or glabrescens (C. auriculata, C. evrardi, C. scabra), fruit shape, the number of wings in fruit, the number of ovules in locute. The study is an effort to understand the morphological delimitation of Colona species in a better way. A taxonomic key to the species along with updated distribution details are provided.