Dactylospora scapanaria

Tentative ID. Many thanks to Peter Döbbeler for pointing out literature on this and similar taxa.

Current name: Dactylospora scapanaria (Carrington) D. Hawksw. Basionym: Lecidea scapanaria Carrington.

“Lecidea” scapanaria was originally found on Carrington’s trip to western Ireland (Carrington, 1863). David Hawksworth recognised the similarity to Dactylospora (Hawksworth, 2003). Upon my finding of similar material, I was struck by its similarity to Stenocybe nitida, including occupying a similar “microniche” on the host of lower, decaying shoots.

Hosts: Gymnomitrion obtusum and G. crenulatum.

Blackish apothecia on short stalks. Material from Merionethshire, VC48, Sept 2021
Asci with 3-septate ascospores with paler ends in water. Material from Merionethshire, VC48, Sept 2021
Figure from Carrington, 1863 – refer to the plate. His drawings do not show the obvious constricted septum seen in my material and the spores look somewhat longer and more fusiform. A re-evaluation of the type material would be most helpful.

Some additional but not scaled images…

Young fruitbody developing on lower region of shoot (checked as globose structure resembles Bryomyces gymnimitrii / Pleostigma jungermannicola). Younger apothecia like this were frequent, buried among the shoots. Smaller spots are Bryochiton microscopicus, abundant.
8-spored ascus + some displaced immature ascospores.
Ascospore arrangement biseriate, contrasting with Stenocybe nitida which appears to have rather consistent uniseriate arrangement and cylindrical asci (but need to study material)
Some free spores in water.