Thallus absent, lichenicolous.
There are three lichenicolous species of Diplotomma recorded from GBI; D. parasiticum has smaller ascospores than those of D. murorum (on Pyrenodesmia teicholyta) and D. vezdanum (on Polycauliona verruculifera).
Arthonia apotheciorum is another lichenicolous fungus which causes black spots on the apothecial discs of Myriolecis dispersa agg. apothecia and these two lichenicolous species are unreliably identified in the field.
On thalli of Myriolecis antiqua and M. dispersa agg., not causing substantial damage to the host lichen.
Known from single sites in VC17 Surrey and VC82 E Lothian.