THE APPLICATION OF LEAF ANATOMY IDENTIFYING SPECIES OFORCHIDANTHA N.E.BR. (LOWIACEAE RIDL.) IN MALAYSIA

Lowiaceae only consists of one genus, Orchidantha, which, with thirty-four species, has the lowest number of species among the eight families within the order Zingiberales. Recently, Orchidantha has garnered attention for its potential medicinal value in treating fever, cough, and chest and back pain. The species are often only found in a small area. The morphology of the flower of Orchi-dantha is essential to identification, but often the flowers are rarely found. As a result, this study aims to investigate vegetative anatomical characteristics of the petiole, midrib, and lamina, which could be used for species identification independent of the availability of flowers by identifying shapes and special characteristics of the labellum, stigma, and viscidium. The results of this study show a marked difference in the shape and depth of the petiole grooves, the petiole margin, and the number of vascular systems. In conclusion, the study demonstrates that the anatomical‒petiole grooves, petiole margin, and number of vascular systems are useful for identifying species. Key words: Anatomy, diagnostic characters, Lowiaceae, petiole grooves, vascular systems