Biosystematic Study Of The Fern Genus Diplazium In West Malesia

Abstract

Diplazium is a large genus consisting of about 400 species occur mainly in the tropics, sparingly in the subtropic and only locally extending into temperate. It was estimated that 300 species of the records were occurred in Malesia. Taxonomically, Diplazium is very difficult and quite insufficiently known. Therefore a comprehensive study on Diplazium in West Malesia was conducted by using morphological, ecological, geographic distribution, anatomical, palinological, cytological, as well as DNA analysis to understand the diversity and relationship among species. Based on gross morphological study on 1051 collection number of specimens as well as living collections, it was concluded that West Malesian Diplazium comprises of 69 species with 14 varieties. Thirteen species of them are proposed and described as new species, namely Diplazium asymmetricum, D. batuayauense, D. crameri, D. densisquamatum, D. halimunense, D. loerzingii, D. megasegmentum, D. megasimplicifolium, D. meijeri, D. parallelivenium, D. profluens, D. subalternisegmentum, and D. subvirescens. Two new varieties are poposed, namely D. accedens var. spinosum and D. silvaticum var. pinnae-ellipticum. D. pallidum var. montanum and D. accedens var. ridleyi are proposed as new status.