Taxonomic Study of the subtribe Andrographinae, tribe Ruellieae, family Acanthaceae in Thailand

Abstract

The Andrographinae is one of the famous subtribes in the Tribe Ruelliae (Acanthaceae). The most famous genera in this subtribe are Andrographis Wall ex Nees, Graphandra Imlay, Gymnostachyum Nees and Phlogacanthus Nees. Their large diversity was found in various tropical countries including Thailand. However, thereis no revision of their diversity in Thailand for decades. Thus, this study aimed to collect and revise the species list for the Flora of Thailand. Data was collected from relevant previous documents, herbarium specimen supplied from 5 herbaria, and field survey across country during October 2009 to September 2010. Morphological characters including pollen morphology were determined and recorded.Twenty-three species of the Andrographinae were found in this study viz. Andrographis (2), Grapahndra (1), Gymnostachyum (8), and Phlogacanthus (12). The differences of morphological characters among them were discussed and the checklist of the subtribe was provided.