DIATOMS OF SINGAPORE AND PENINSULAR MALAYSIA

Abstract

A total number of 380 taxa was recorded from 17 families and 66 genera. The most common family was Naviculaceae with 138 taxa, followed by Eunotiaceae with 42 taxa and Fragilariaceae 42 taxa. Of these 380 taxa, 287 were recorded from Singapore and 229 from Peninsular Malaysia. Collections were made from freshwater, marine, mangrove, sub-aerial and terrestrial habitats. Marine habitat yielded the most number of diatoms with 239 taxa, followed by freshwater (118 taxa), mangroves (73 taxa) and subaerial (62 taxa ) . Terrestrial habitats had the least number of diatoms with 9 taxa only. Naviculaceae was the commonest family in all the habitats with Fragilariaceae, Coscinodiscaceae and Bacillariaceae as the commoner families. Rivers, reservoirs, lakes and ponds were rich in diatoms while stagnant pools and drains supported limited number of taxa. Eunotia, Navicula and Pinnularia were plentiful in rivers. More Eunotia spp. were collected from one location in Peninsular Malaysia, the undisturbed jungle of Ulu Endau because this genus favours unpolluted freshwater streams. There were more marine diatoms collected from Singapore (188 taxa) than Peninsular Malaysia (149 taxa) and Thailand (26 taxa ) . Almost all the diatom taxa were collected from seaweed whiIe most of the mangrove diatoms were from mud. The other substrata rich in diatoms were molluscs, debris, roots and stems of mangrove plants. There were lesser number of diatoms from subaerial and terrestrial habitats. Most of these were collected from concrete, brick and rock surfaces.