Lecidella greenii U. Ruprecht & Türk
Mycobank MB 517793
Thallus crustose, whitish, grey, beige, well-developed, rimose to areolated and sometimes granulose; chasmolthitic and epilithic, up to 1 mm high and 5 cm in diam. Pycnidia infrequent, up to 0.2 mm; photobiont Trebouxia sp. Apothecia in dense groups; visible margin when young, inconspicuous when old and large; black, matt disk, flat to convex, up to 1.2 mm in diameter, sessile, constricted at the base. Epihymenium up to 10 µm, olive to dark green; hymenium 80–90 µm, hyaline to light brownish when mature, inspersed; Paraphyses simple, 1–2 µm in diam., rarely anastomosing, flexuous, slightly adglutinated, end cell dark green to olive and slightly thickened to 4 x 4 µm; subhymenium up to 40 µm, hyaline to light green; hypothecium hyaline, inspersed with brown crystals; excipulum to 200 µm broad, I–, hyaline, dark green margin, of radiate hyphae; asci of the Lecidella-type, 40–50 µm long; ascospores 8/ascus, non-septate, hyaline, 10–11(–12) x 6–7(–8) µm, broadly ellipsoid, length-width index 1.5–1.6. Secondary chemistry: chemotype I: nil, chemotype II: stictic acid chemosyndrome; spot tests: K– or K+ yellow, I–, C–.
The widespread genus Lecidella comprises c. 50 species worldwide. These crustose lichens occur on tree bark as well as on mosses, sand and rocks. The genus is characterized by small black lecideoid ascomata and Lecidella-type asci (Knoph & Leuckert 2004). The new species is one of two species of Lecidella occurring in continental Antarctica. It is identified by the shape and size of its ascospores, its exclusively saxicolous habit and its secondary chemistry that clearly sets this lichen apart from all other species of Lecidella so far described.
Dedicated to T. G. Allan Green, University of Waikato, New Zealand.
So far endemic to continental Antarctica, on granite rock and sandy soil.
Type:—ANTARCTICA: Ross Dependency: Transantarctic Range, Granite Harbour; 77°00’S, 162°31’E; Jan 2008, Türk 43015 (holotype SZU; isotype A).
Additional specimens examined (paratypes):—ANTARCTICA: Ross Dependency: Transantarctic Range, Granite Harbour; Türk 43007, 43013, 43014, 43015, 43017, 43029 (SZU); Taylor Valley; Türk 33611, 33612, 33620, 33628, 33586, 33630, 33649, 33659, 33700, 33706 (SZU); Mt Suess; Türk 42999 (SZU) .
Thallus crustosus, areolatus, albidus. Apothecia lecideina, Asci ad typum Lecidella pertinens, Ascosporae hyalinae, non-septatae, ellipsoidae, 10–11(–12) x 6–7(–8) µm.