This is an interactive identification tool for 100 species of lichens commonly occurring in Thailand, prepared on the occasion of a workshop held in Bangkok in June 2017. Of course, this guide cannot be used to identify all lichens found in the Country, but it may be useful as a tutorial in workshops and courses for students and beginners, who will be asked to identify only the species which are included in the key. In this way, they will learn the basic terminology, and will make the first steps in lichen identification. The online key has two query interfaces: 1) A fully illustrated dichotomous interface, 2) A multi-entry interface where the user can select several characters at a time. At the end of the query, if several species share the specified set of characters, the system produces a dichotomous key for those species only. The dichotomous key is also available in several stand-alone versions: printable, CD-Rom, and for mobile devices via the free app KeyToNature (Android and iOS). The key has been created using program FRIDA (Martellos 2010, Martellos & Nimis 2015) at the Department of Life Sciences of the University of Trieste (Italy), and will be further tested and implemented at the Department of Biology of the Ramkhamhaeng University, Bangkok, to encompass a broader set of species. The pictures of species were in part provided by the Lichen Herbarium of Ramkhamhaeng University, Dept. of Biology, Faculty of Science, Bangkok, and , and in part derive from other sources, especially the online site http://www.tropicallichens.net/.

Literature
Martellos S. (2010) - Multi-authored interactive identification keys: The FRIDA (FRiendly IDentificAtion) package - Taxon 59 (3): 922-929.
Martellos S. & P.L. Nimis (2015) - From Local Checklists to Online Identification Portals: A Case Study on Vascular Plants. – PlosONE, https://doi.org/10.1371/journal.pone.0120970

Pictures – Credits

Pictures of Astrothelium meristosporum, Astrothelium subdiscretum, Bathelium madreporiforme, Bathelium nigroporum, Bulbothrix queenslandica, Bulbothrix tabacina, Canoparmelia owariensis, Chrysothrix xanthina, Cladonia homchantarae, Crocynia pyxinoides, Diorygma junghuhnii, Erioderma sorediatum, Gassicurtia omiae, Glyphis scyphulifera, Graphis analoga, Heterodermia lepidota, Hyperphyscia adglutinata, Lecanora helva, Marcelaria benguelensis, Ocellularia perforata, Parmelinella wallichiana, Parmotrema cristiferum, Parmotrema maclayanum, Parmotrema praesorediosum, Parmotrema tinctorum, Phyllopsora soralifera, Physcia undulata, Physma byrsaeum, Platygramme pudica, Pyrenula aspistea, Pyrenula breutelii, Pyrenula immissa, Pyxine coccifera, Pyxine retirugella, Relicinopsis intertexta, Relicinopsis malaccensis, Relicinopsis rahengensis, Sarcographa glyphiza, and Stegobolus fissus - © Lichen Herbarium, Department of Biology, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand

http://dryades.units.it/italic
all images of characters by Andrea Moro - CC BY-SA 4.0
pictures of Diploschistes actinostomus, Endocarpon pallidum, Heterodermia obscurata, Heterodermia speciosa, Leucodermia leucomelos, and Pertusaria leioplaca by Pier Luigi Nimis - CC BY-SA 4.0

http://graphidaceae.fieldmuseum.org/classification
picture of Pallidogramme chrysenteron - © Field Museum of Natural History, Chicago

http://lichenportal.org
pictures of Astrothelium macrocarpum and Dimelaena tenuis - United States National Herbarium, Smithsonian - CC BY-NC

http://mycoportal.org
picture of Sulcopyrenula subglobosa - © Natural History Museum, London

http://www.bgbm.org
picture of Amandinea diorista var. hypopelidna by Harrie Sipman - CC BY-SA-NC

http://www.tropicallichens.net
pictures of Anthracothecium macrosporum, Astrothelium megaspermum, Bacidia medialis, Buellia curatellae, Bulbothrix isidiza, Cladia aggregata, Dirinaria confluens, Haematomma rufidulum, Heterodermia flabellata, Hypotrachyna vexans, Lecanora subimmersa, Leptogium marginellum, Letrouitia transgressa, Parmotrema saccatilobum, Pertusaria cicatricosa, Physcia poncinsii, Polyblastidium microphyllum, Porina mastoidea, Pyrenula anomala, Pyxine berteriana, P. cylindrica, Ramboldia russula, Remototrachyna kingii, and Usnea pectinata by André Aptroot - CC BY-SA-NC
pictures of Graphis streimannii and Phaeographis brasiliensis by Alan W. Archer - CC BY-SA-NC
pictures of Cresponea proximata, Dirinaria picta, Dyplolabia afzelii, Letrouitia domingensis, Leucodecton occultum, Nigrovothelium tropicum, Phaeographis caesioradians, Phaeographis intricans, Rinodina oxydata, Sarcographa labyrinthica, Trypethelium eluteriae, and Usnea baileyi by Harrie Sipman - CC BY-SA-NC
pictures of Parmotrema overeemii and Pyxine cocoës by Laurens Sparrius - CC BY-SA-NC
pictures of Glyphis cicatricosa and Heterodermia comosa by Adriano Spielmann - CC BY-SA-NC
picture of Coccocarpia erythroxyli by Einar Timdal - CC BY-SA-NC
picture of Hypotrachyna nepalensis by Kok van Herk - CC BY-SA-NC

https://www.flickr.com
picture of Polymeridium catapastum by Pat McCarthy - © Pat McCarthy

picture of Leptogium azureum by Felix Schumm - © Felix Schumm

picture of Parmotrema gardneri by Harry Taylor - © Natural History Museum, London

picture of Usnea rubicunda by Tiiu Tõrra - © Tiiu Tõrra, Institute of Ecology and Earth Sciences, University of Tartu, Estonia

picture of Collema coilocarpum by Gothamie Weerakoon - © Gothamie Weerakoon