Magnusson, AH. 1939. Studies on Species of Lecanora, Mainly the Aspicilia gibbosa Group. Kongl. Svenska Vetenskapsakad. Handl. 17: 34-35.
Thallus determinate, thin, dark brown/grayish-brown-ashy grey, outline distinctly radiate, rays contiguous, hypothallus obscure, limited, areolate towards centre, areolae circumference always turned, subdentritic arranged, elongate or regular, slightly convex, rimose, thin, separate, KOH-. Apothecia turned towards centre, +/- crowded, always single, immersed, disc black, plane, surrounded by thin, slightly prominent thalline margin, proper margin indistinct. Medulla granules obscure. Hymenium almost tall, paraphyses submoniliform. Spores almost moderately sized.
Thallus at least 5 X 7 cm diam., C.U.C. 233, 495, marginal lobes 2-4 mm long, 0.2-0.4 mm broad, about 0.2 mm thick, convex, generally contiguous, rarely somewhat discrete, towards the centre transformed into lengthened areolae, 1 mm long, 0.3-0.6 mm broad, forming +/- distinct, branched lines, partly with the stone visible between them, thallus in this way partly dendroid. Central areolae +/- angular, 0.2-0.3 mm thick, separated by distinct cracks, on the whole slightly convex.—Cortex 30-35 µ thick, opaque, upper 4-6 µ brown-olive, amorphous stratum 3-5 µ thick, even. Cells concealed by granules, dissolving in HCl, then 2-3.5 µ, globular, +/- thick-walled. Gonidia 10-16 µ, stratum 30-35 µ, not dense, with granules. Medulla dark gray, in HCl with distinct, perpendicular hyphae, 4-6 µ, thick-walled, with rich content of oil, without stone fragments.
Apothecia sometimes 2-3 in the central areolae, De 100-120, discs (0.2)0.3-0.4 mm large, impressed.—Apothecia about 200 µ deep. Exciple 30-50 µ thick at the base, indistinctly cellular, laterally 10-12 µ, +/- refracting, towards surface indistinct or widened with upper 20-25 µ olive-brown, I- or indistinctly blue. Hypothecium about 35 µ thick, cloudy. Hymenium 85-100 µ high, I+ dark green or brownish-yellow like the hypothecium and exciple; upper 15-20 µ +/- olive. Paraphyses 1.7 µ in water, +/- guttulate and thin-walled, in KOH generally simple, apices still coherent, 2.5-3 µ thick, lumina mostly oblong, paraphyses +/- constricted at the joints or +/-submoniliform. Asci 75-85 X 17-19 µ. Spores 8, rarely fully developed, 12-14(17) X 8.5-9.5 µ, in KOH subglobose.
One pycnide about 200 µ broad, conidia 17-20 X 0.6 µ.
Habitat. On calciferous, slaty rock.
Distribtuion. Sweden Jämtland: Storlien, mountains to the west of Skurdalshöjden 1914 Mn (in hb., Gbg.), VRANG (in hb., R.).—Nov. Zemlya. Matotchkin Shar: Vasnetsoff Glacier 1921 LYNGE (O.).
L. dendroplaca is perhaps nearly related to L. plicigera hat (sic) has quite another arrangement of the areolae towards the margin, much shorter conidia and not distinctly moniliform paraphyses. The dendroid formation of the areolae is generally very obvious. The N. Zemlya specimen called L. supertegens by ZAHLBRUCKNER has a rather distinct proper apothecial margin and branched paraphyses but the same dendroid arrangement of the areolae and seems to me to be placed under L. dendroplaca most appropriately. Unfortunately, conidia have not been found. Hym. 100-120 µ.