Heterodermia dissecta (Kurok.) D.D. Awasthi, Geophytology

Mongkolsuk, Pachara, Meesim, Sanya, Poengsungnoen, Vasun, Buaruang, Kawinnat, Schumm, Felix & Kalb, Klaus, 2015, The lichen family Physciaceae in Thailand-II. Contributions to the genus Heterodermia sensu lato, Phytotaxa 235 (1), pp. 448-450 : 448-450

6. Heterodermia dissecta (Kurok.) D.D. Awasthi, Geophytology 3(1): 113 (1973) ( Fig. 7B )

Anaptychia dissecta Kurok., J. Jap. Bot. 34(6): 182 (1959). Type :— JAPAN. Mikawa : Mt. Horaiji, 7 January 1956, Kurokawa 56029 (holotype TNS, fide Kurokawa 1959; isotype H!).

Thallus foliose, orbicular to irregularly spreading, loosely adnate, 5–10 cm wide. Lobes 0.7–2.0 mm wide, plane to weakly convex or weakly concave, sublinear-elongate, sympodially to subdigitately branched; apices not ascending, ± discrete to contiguous at the periphery, with short lateral lobes, eciliate. Upper surface gray-white to gray, epruinose, with marginal phyllidiate isidia or dorsiventral lobules that are ± granular; marginal phyllidia usually minutely dissected, often granular near the tips, or entire phyllidia becoming granular and appearing sorediate. Medulla white. Lower surface with a pseudocortex, white (sometimes rose-red spotted if norstictic acid is decomposing) to grayish or pale brown at the centre, smooth, rarely slightly corrugated. Lower surface rhizines rare or even absent, whitish to cream, concolorous with the thallus or becoming pale to dark brown towards the apices, simple to irregularly branched, marginal rhizines numerous, mostly simple, becoming irregularly branched and black with age, 0.3–1.5 mm long, ± projecting beyond the lobe margins. Apothecia very rare, laminal, sessile

THE LICHEN FAMILY PHYSCIACEAE IN THAILAND —II

Phytotaxa 235 (1) © 2015 Magnolia Press • 19 to substipitate, 1–5 mm wide; margin lobulate-isidiate; disc concave, brown to brownblack, epruinose. Ascospores Pachysporaria - type, ellipsoidal, 28–32 × 12–16 µm. Pycnidia rare, initially immersed, becoming emergent, visible as black dots; conidia bacilliform, 4–5 × 1 µm.

Chemistry: Cortex K+ yellow, C–, KC–, P+ yellow; medulla K+ yellow then red, C–, P+ dark yellow; containing atranorin (major), zeorin (major), 16β-acetoxyhopane-6α,22-diol (major), 6α-acetoxyhopane-16β,22- diol (trace), leucotylin (minor), dissectic acid (major to minor), norstictic acid (major), connorstictic acid (major to trace).

Distribution and habitat:—Occurs on rocks and on the bark of unidentified trees in evergreen mountain

20 • Phytotaxa 235 (1) © 2015 Magnolia Press

MONGKOLSUK ET AL.

forest, lower montane scrub, tropical rainforest and lower montane forest from 765–1595 m above sea level, also in Australia, Réunion, India, China and Japan; new addition to the Thai lichen biota.

Remarks:—This lichen is characterized by the minutely dissected marginal lobules and/or phyllidia that often appear granular sorediate and the presence of norstictic and dissectic acids.

Material from Thailand examined:— Chiang Mai: Lumphun, Mae On, descent from Doi Mon Larn to Mae Kam Pong village, in evergreen mountain forest, on rock over mosses, 1500 m, 18°51'22'' N, 99°22'02'' E, 19 March 2008, K. Kalb & al. (hb. KK 37038); Loei: Phuluang Wildlife Sanctuary, area of Kok Nok Kraba, along trail to channel 7, in lower montane scrub, on bark of unidentified tree, 1470 m, 17°16'53'' N, 101°31'23'' E, 13 November 2008, S. Meesim & K. Buaruang, RU-MS 0275, ( RAMK 20972); Phitsanulok, Phu Hin Rong Kla National Park, area of Political and military schools, in tropical rainforest, on bark of Castanopsis sp. , 1165 m, 16°59'33'' N, 100°00'42'' E, 5 June 2003, P. Mongkolsuk RU-PM 140, ( RAMK 21411); ibid., on rock, 1165 m, 16°59'33'' N, 100°00'42'' E, 5 June 2003, P. Mongkolsuk RU-PM 136, ( RAMK 21767); ibid., along trail to the Tub Boek area, in lower montane forest, on bark of unidentified tree, 1595 m, 16°55'33'' N, 100°05'58'' E, 1 April 2004, P. Mongkolsuk RU-PM 262/1, ( RAMK 21815); ibid., P. Mongkolsuk RU-PM 262, ( RAMK 21814); Nakon Ratchasima: Khao Yai National Park, 'Pha Klua Mai' nature trail to Heo Suwat waterfall, in tropical rainforest, bark of unidentified tree, 760 m, 14°26'19'' N, 101°24'25'' E, 30 October 1997, T. Pooprang RU-9140, ( RAMK 5550).

Figures

FIGURE 7. A. Heterodermia diademata (scale 1 cm). B. Heterodermia dissecta (scale 5 mm). C. Heterodermia firmula (scale 5 mm). D. Heterodermia granulifera (scale 1.5 mm). E. Heterodermia isidiophora (scale 5 mm). F. Heterodermia isidiophorella (scale 2 mm).