Kalbionora palaeotropica Sodamuk, Leavitt & Lumbsch, gen. et

Sodamuk, Mattika, Boonpragob, Kansri, Mongkolsuk, Pachara, Tehler, Anders, Leavitt, Steven D. & Lumbsch, H. Thorsten, 2017, Kalbionorapalaeotropica, a new genus and species from coastal forests in Southeast Asia and Australia (Malmideaceae, Ascomycota), MycoKeys 22, pp. 15-25 : 15-17

Kalbionora palaeotropica Sodamuk, Leavitt & Lumbsch, gen. et sp. nov. Figure 1

Type.

THAILAND, Trat Province: Muang District, Nhong Sa Nho Subdistrict, the route to Nature Education Center Ban Pak Khlong Nam Chiew, on the bark of Ceriops tagal (Perr.) C.B.Rob., 2014, M. Sodamuk RAMK-24530 (holotype: RAMK; isotypes: F, S).

Diagnosis.

Characterized by having asci of the Catillaria -type, yellowish brown, granulose epihymenium, exciple consisting of prosoplectenchymatous cells, dark brown hypothecium, hyaline, 1-3 transversely septate ascospores, and the presence of atranorin, zeorin, and the stictic and arthothelin chemosyndromes.

Etymology.

The specific epithet refers to the occurrence of the species in the Paleotropics, whereas the genus is named after our colleague Klaus Kalb who has made tremendous contributions to our knowledge of tropical lichens and who has been enormously helpful to colleagues in Thailand.

Description.

Thallus crustose, corticolous, greenish grey to whitish grey (green fading in herbarium); surface continuous, verruculose, somewhat glossy, prothallus not visible; isidia and soredia absent; corticate, cortex 25-40 µm thick, covered by a thin, epinecral layer; photobiont chlorococcoid; medulla indistinct, penetrating into the periderm. Ascomata apothecia, simple, dispersed to crowded, disc plane to convex, grayish green to gray, 0.6-1.6 mm diam.; margin white to whitish grey, thick, entire to flexuous; exciple biatorine, prosoplectenchymatous, incrusted with numerous crystals; hymenium clear, amyloid; paraphyses simple to slightly branched, apically not or slightly thickened; epihymenium distinct, yellowish brown, granulose with numerous small brown crystals, rapidly dissolving in KOH, 3-4 µm thick; hypothecium brown to dark brown, 100-140 µm thick; asci cylindrical, tholus uniformly amyloid, corresponding to the Catillaria -type of Hafellner (1984); ascospores 8 per ascus, uniseriate, hyaline, thin-walled, non-halonate, ellipsoid, 1-3 transversely septate, non-amyloid; (8.0)8.9 –10.4– 11.8(16.0) × (2.5)3.2 –3.8– 4.4(5.5) µm. Pycnidia not found.

Secondary chemistry.

Thallus K+ yellowish, C–, P+ yellow; containing atranorin, stictic acid and zeorin as major constituents, and cryptostictic acid, norstictic acid, peristictic acid, and the chlorinated xanthones arthothelin and 6-O-methylarthothelin as minor compounds (Australian sample analyzed by J.A. Elix).

Distribution and ecology.

The new species was found in coastal forests in eastern Thailand, Vietnam, and northeastern Australia (Queensland), growing on bark. It is known only from a few localities but is expected to be more common and potentially overlooked in mangrove forests of Southeast Asia and Australia.

Notes.

Morphologically similar is the genus Malmidea - some species have similar ascoma morphology and the ascus in this genus also lacks amyloid structures in the thallus. However, this genus can be easily separated by having non-septate, halonate, thick-walled ascospores, and lacking depsidones. Further, molecular evidence suggests that the genera are only distantly related. Another morphologically similar genus is Eugeniella and both Eugeniella and the new genus also share similar ascospore septation. However, these taxa readily distinguished by the ascus-type ( Byssoloma -type in Eugeniella ), the exciple (composed of moniliform hyphae in Eugeniella ), and the epihymenium (usually indistinct in Eugeniella ) ( Breuss and Lücking 2015; Cáceres et al. 2013a). The new genus might be confused in the field with the superficially similar, common, pantropical Lecanora caesiorubella or has been confused with Dirina paradoxa , but is readily distinguished by numerous anatomical characters and a different chemistry.

Specimens examined.

Australia, Queensland: Daintree National Park, Cape Tribulation, c. 63km N of Mossman, in a dense tropical, coastal rainforest, dominated by Pandanus sp., 2008, K. Kalb 37355 (hb. Kalb). Thailand, Trat Province: Muang District, Nhong Sa Nho Subdistrict, the route to Nature Education Center Ban Pak Khlong Nam Chiew, on the bark of Ceriops tagal (Perr.) C.B.Rob., 2011, M. Sodamuk, RAMK-24241, 24242 & 25036 (RAMK); ibid., 2014, M. Sodamuk, RAMK-24531, 24532 & 24533 (RAMK); ibid., Excoecaria agallocha L., 2011, M. Sodamuk, RAMK-25035 (RAMK). Vietnam, Dak Lak Province: Buon Ma Thuot City, Museum, 19 Feb 2013, Oh & Thanh, VN130046 (KoLRI).