Inoderma subabietinum, Lecanactis subabietina Roccellaceae
Inoderma subabietinum (Lecanactis subabietina)

Growth type crustose
Pycnidial pruina K+/- light yellow, C-, UV+ ice-blue, K/UV+ mauve

Found on the dry, shaded side of trunks and bases of old Oaks and other acid-barked trees. Also found on thick Ivy stems. Most frequent in coastal areas of SW England.
BLS conservation evaluation: LC Sc IR. NIEC 'Old woodland' indicator

Thin whitish-grey thallus with abundant globose, white-pruinose, black pycnidia, often with extruded yellowish conidial mass. Apothecia unknown. Conidia 3.7-5 x 1.2-1.7 Ám. Microscope photograph below.

Similar: Opegrapha vermicellifera. Chemical and UV reactions negative
Lecanactis abietina. Thallus UV+ yellow or glaucous grey. Pruina C+ red

Lecanactis subabietina

Lecanactis subabietina

Microscope photograph
Lecanactis subabietina, conidia
Inoderma subabietinum (Lecanactis subabietina)
Holton Lee and Studland, Dorset. October 2012 and December 2013

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