ISSN (print) 0093-4666 © 2013. Mycotaxon, Ltd. ISSN (online) 2154-8889 MYCOTAXON http://dx.doi.org/10.5248/123.479 Volume 123, pp. 479–489 January–March 2013 New records of corticolous lichens from Vietnam Santosh Joshi 1 , Thi Thuy Nguyen 2 , Nguyen Anh Dzung 2 , Udeni Jayalal 1 , Soon-Ok Oh 1 & Jae-Seoun Hur 1 * 1 Korean Lichen Research Institute, Sunchon National University, Suncheon-540 950, Korea 2 Department of Basic Biology, Faculty of Natural Science and Technology, Tay Nguyen University, Buon Ma uot City, Dak Lak Province, Vietnam Correspondence to *: jshur1@sunchon.ac.kr Abstract —Eight new records of crustose lichens are reported from Dak Lak, Dak Nong, and Vinh Phuc provinces in Vietnam. Descriptions of Diorygma hieroglyphicum, Letrouitia leprolytoides, L. transgressa, Ocellularia perforata, Opegrapha robusta, Platythecium colliculosum, P. dimorphodes, and Syncesia farinacea include morphological, anatomical, chemical characters, and comparisons with similar taxa. Key words—Graphidaceae, Letrouitiaceae, Roccellaceae, evergreen forest, tropical Introduction A recent survey suggested that lichen species richness increases towards lower latitudes and that tropical ecosystems harbor about half of the total lichen species known worldwide (Lücking et al. 2011). Vietnam, part of the Eastern palaeotropical region, provides a climate suitable for lichens, particularly crustose, corticolous, and foliicolous species (Nguyen et al. 2010, 2011). Sporadic surveys and lichen collections from different regions of this country indicate that the majority of its land is still unexplored for its lichen diversity. Aptroot & Sparrius (2006) provided the first checklist of Vietnamese lichens, but no update has been published since. However, recent publications (Giao 2009; Nguyen et al. 2010, 2011) on foliose and foliicolous lichens in Vietnam document the potential richness in lichens in this region, and suggest that many more species have not yet been recorded. We report here eight corticolous species representing Diorygma, Letrouitia, Ocellularia, Opegrapha, Platythecium, and Syncesia as new for Vietnam. Species in four of these genera have previously been recorded from Vietnam: Diorygma tinctorium Eschw., Letrouitia domingensis (Pers.) Hafellner & Bellem., Ocellularia allosporoides (Nyl.) Patw. & C.R. Kulk., O. asiatica (Vain.) Hale,