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Lichenochora obscuroides (Lindsay) Triebel & Rambold
Family: Phyllachoraceae
[Lecidea obscuroides Linds.,  more]
Lichenochora obscuroides image
Mycelium: immersed, hyaline, inconspicuous but inducing the formation of galls on the host thallus; galls: regular, only slightly convex, concolorous with the host thallus or somewhat darker, containing several ascomata of which only the ostioles are visible Perithecia: spherical to broadly pyriform, 180-240 µm in diam., with many lipid droplets in all parts; wall: brown, 20-30 µm thick, composed of 4-5 layers of tangentially flattened cells hymenium: lining the lower half of the ascomatal cavity hamathecium: present as paraphyses and periphyses paraphyses: hyaline, 3-5 µm thick, with some branches or unbranched, with delicate walls, dissolving in older ascomata periphyses: numerous, mostly unbranched, forming a distinct crown above the asci, 2-4 µm thick, with distinctly longer terminal cells asci: cylindrical to slightly clavate, 50-70 x 9-14 µm, 8spored ascospores: hyaline, 1-septate, elliptical to oblong, with delicate wall and without a distinct perispore, 15-18 x 5-7 µm Pycnidia: not observed. Hosts: thallus of Phaeophyscia hispidula, outside the Sonoran region also Phaeophyscia orbicularis, P. pusilloides, and P. rubropulchra; gall inducing, partly killing the algal cells of the hosts, but not the entire lichen thallus World distribution: widely distributed in Europe from northern Scandinavia to the Mediterranean, also recorded from several scattered localities in North America (Canada, U.S.A.) Sonoran distribution: known only from a few localities in northern Arizona and Baja California Sur, all at higher altitudes. Notes: Lichenochora obscurioides, a taxonomic synonym of which is the type of the genus, is easily recognized by its conspicuous galls, that are mostly slightly darker than the healthy host thallus. The few scattered records in North America (British Columbia, Michigan, New York, Arizona) indicate a continent-wide distribution.