Thelidium incavatum Verrucariaceae
Thelidium incavatum

Growth type crustose
Chemical results negative

Common on limestone and other calcareous rocks in graveyards and on natural outcrops

Thallus white, greyish or discoloured brown, perithecia immersed in pits but sometimes with the apex projecting. Asci are 8-spored, the spores hyaline, (28)36-46(54) × (11)13-16(20) µm, 3(-5) septate, occasionally with one or two longitudinal septa. Microscope photograph below.

Similar: Can be very hard to distinguish from Polyblastia dermatodes.
Thelidium decipiens has 1-septate spores.


Thelidium incavatum

Thelidium incavatum

Thelidium incavatum

Microscope photographs
Thelidium incavatum

Thelidium incavatum

Thelidium incavatum
Thelidium incavatum
Wimborne and Puddletown, Dorset. February and May 2017

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