The lichen family Physciaceae in Thailand-II. Contributions to the genus Heterodermia sensu lato Author Mongkolsuk, Pachara Lichen Research Unit, Biology Department, Faculty of Science, Ramkhamhaeng University, Ramkhamhaeng 24 road, Bangkok, 10240 Thailand. Author Meesim, Sanya Lichen Research Unit, Biology Department, Faculty of Science, Ramkhamhaeng University, Ramkhamhaeng 24 road, Bangkok, 10240 Thailand. Author Poengsungnoen, Vasun Lichen Research Unit, Biology Department, Faculty of Science, Ramkhamhaeng University, Ramkhamhaeng 24 road, Bangkok, 10240 Thailand. Author Buaruang, Kawinnat Lichen Research Unit, Biology Department, Faculty of Science, Ramkhamhaeng University, Ramkhamhaeng 24 road, Bangkok, 10240 Thailand. Author Schumm, Felix Mozartstrasse 9, D- 73117 Wangen, Germany. Author Kalb, Klaus Lichen Research Unit, Biology Department, Faculty of Science, Ramkhamhaeng University, Ramkhamhaeng 24 road, Bangkok, 10240 Thailand. & Lichenologisches Institut Neumarkt, Im Tal 12, D- 92318 Neumarkt, Germany. Email: klaus. kalb @ arcor. de & Lichen Research Unit, Biology Department, Faculty of Science, Ramkhamhaeng University, Ramkhamhaeng 24 road, Bangkok, 10240 Thailand. & University of Regensburg, Institute of Plant Sciences, Universitätsstraβe 31, D- 39040 Regensburg, Germany Corresponding author-email: pm-tamrapap @ ru. ac. th & Lichen Research Unit, Biology Department, Faculty of Science, Ramkhamhaeng University, Ramkhamhaeng 24 road, Bangkok, 10240 Thailand. klaus.kalb@arcor.de text Phytotaxa 2015 2015-11-20 235 1 448 450 http://dx.doi.org/10.11646/phytotaxa.235.1.1 journal article 10.11646/phytotaxa.235.1.1 1179-3163 13631327 2. Polyblastidium chilense (Kurok.) Kalb , comb. nov. Mycobank MB 813839 Basionym: Anaptychia chilensis Kurok., Beih. Nova Hedwigia 6: 65 (1962) . Type :— CHILE . Valparaiso ; Alto del Puerto, on soil at a small stream in a creek, 14 August 1940 , R. Santesson 2919 ; (S!); Heterodermia chilensis (Kurok.) Swinscow & Krog, Lichenologist 8: 115 (1976) . Thallus foliose, orbicular to irregularly spreading, adnate, 2–5 cm wide. Lobes 0.7–1.5 mm wide, slightly more narrow at the apices, plane to convex, sublinear to sublinear-elongate, dichotomously to digitately branched, ascending at the apices, with a few short lateral branches, eciliate. Upper surface whitish gray to pale yellow-brown, uneven, pruinose at the apices, sorediate; soralia apical, labriform, originating from the reflexed underside. Medulla white. Lower surface ecorticate, ± compact or granular towards the tips, white, lacking pigments, canaliculate, with thick corticate margins. Rhizines marginal, concolorous with the thallus to brown-black, simple to digitately divided, 0.7–2.0 mm long. Apothecia laminal, sessile to substipitate, 1.0– 1.5 mm wide; margin pruinose; disc brown-black, Ascospores Polyblastidia - type , ellipsoidal, with 0–2 small sporoblastidia, 25–39 × 15–22 µm. Pycnidia initially immersed, later weakly emergent, visible as black dots; conidia bacilliform, 4–5 × 1 µm. Chemistry: Cortex K+ yellow, C–, KC–, P+ yellow; medulla K+ yellow, C–, P–; containing atranorin (major), zeorin (major), 6α-acetoxyhopane-16β,22-diol (minor), 6α-acetoxy-22- hydroxyhopane-25-oic acid (minor), 6αacetoxy-16β,22-dihydroxyhopane-25-oic acid (minor). Distribution and habitat :—Occurs on mossy rocks, rarely on tree bases in Australia , South America, South and East Africa and New Zealand and probably also in Thailand . 40 • Phytotaxa 235 (1) © 2015 Magnolia Press MONGKOLSUK ET AL. Remarks : — This lichen is characterized by the saxicolous or terricolous habitat, the apical, white, labriform soralia, the white, ecorticate lower surface with corticate margins, and by the presence of the speciosa chemosyndrome of triterpenes, i.e. 6α-acetoxyhopane-16β,22-diol, 6α-acetoxy-22-hydroxyhopane-25-oic acid and 6α-acetoxy-16β,22-dihydroxyhopane-25-oic acid. The only report for Thailand is from the RAMK checklist. We did not find this species in the material investigated, but as it is possible that it occurs in the country, we have included it in the key and provided a description from the type specimen.