ACANTHUS TAXA IN SINGAPORE

Abstract

The genus Acanthus L. has about 30 tropical and subtropical species, out of which, three to four are mangrove species that used to be classified under a different genus, Dilivaria Juss. (Bremekamp, 1955a). Three of them occur in Singapore, namely A. illicifolius L., A. ebracteatus Vahl and A. volubilis Wall. (Turner, 1993; Tan, Soong and Morgany, 1995). There had always been confusion concerning the identification of these plants. All three species display phenotypic plasticity, especially in lamina, and similar looking flowers of Acanthus ebracteatus and A. volubilis in Malesia (Steenis, 1936; Tomlinson, 1986). To help in delimitation of this group of plants, amplified fragment length polymorphism (AFLP) is employed. The data is analyzed using the unweighted pair-group arithmetic average (UPGMA) and Neighbour-joining methods found in the software phylogenetic analysis using parsimony (P AUP) for generation of dendrograms. Results show distinct differences between A. ilicifolius and the other two groups A. ebracteatus and A. volubilis. However, the results could not determine the status of A. ebracteatus and A. volubilis satisfactorily.