Family: Naetrocymbaceae Species: Tomasellia gelatinosa Growth type crustose Photos: Commeen West, Co. Cork, SW Ireland. Thallus inconspicuous but slightly bleaching the bark, the brown or blackish, +/- round ascomata with up to 12 perithecia-like locules. Asci 8-spored, spores (1-)3 septate, 20-28 x (5-)7-8(-10) µm, hyaline, becoming dark-brown with age. Pycnidia with colourless, bacilliform conidia. Chemical results negative. Photobiont is absent but chlorococcoid algae are often present on the bark surface. Micrographs below Occurs on the trunks and branches of various trees and shrubs but most frequent on Corylus Similar: Tomasellia diffusa, on Alnus, spores brown, 1-septate

Micrograph



Tomasellia gelatinosa. June 2025