Abstract
Begonia sibthorpioides subsp. machinchangensis is a newly described taxon restricted to Gunung Machinchang, Langkawi Island, Malaysia. Based on recent collections of this new subspecies and B. sibthorpioides from its type locality of Gunung Jerai, Kedah, detailed morphological comparison has revealed distinguishing characters between these two sandstone-restricted taxa such as indumentum, stipules, bracts, scale-like hairs on tubers, leaf thickness and impressed venation. Descriptions and illustrations for the new subspecies and the type subspecies are provided, and they are also compared to other species, i.e. B. hymenophylla, B. sinuata and B. thaipingensis. Genetic distance based on analysis of chloroplast ndhF-rpl32 sequences supports the delimitation of B. sibthorpioides into two subspecies, and Bayesian phylogenetic analysis showed monophyly of these three species where B. sinuata and B. thaipingensis formed a clade which is sister to B. sibthorpioides. Provisional conservation status assessment using IUCN Red List Criteria indicates B. sibthorpioides subsp. machinchangensis is Critically Endangered (CR) due to its restriction to particular microhabitat of single locality and the population being threatened by new infrastructure development for tourism.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
