Muellerella sp. P4200
This possibly represents the holomorph of Lichenodiplis lecanorae, but the material is scanty and that species is polyphyletic according to Muggia et al. (2019). Ascomata are pyriform, 50-60 µm diam. and 65-75 µm tall, the peridium composed of about four layers of flattened mid brown angular cells. Asci are 32- or 64-spored, with ascospores initially aseptate but eventually becoming 1-septate when they are cylindric-ellipsoidal, pale brown and measure ca 5 x 2 µm. The conidiomata are ca 40 µm diam. and ± globose with a gaping ostiole, the inner wall lined with ± cylindrical conidiogenous cells ca 5 x 2 µm. Conidia are 5.5-6 x 2.8-3.5 µm, ellipsoidal, not contricted at the median septum, mid brown, thin-walled, the base ± truncate.
On degraded thalli of Lecanora ? poliophaea in assocation with a conspicuous black, possibly cyanobacterial crust, on maritime schistose rock.
Reported from a single site in VC52 Anglesey.