Blue Blister Lichen Thalloidima sedifolium

Suffolk Priority Species

The Blue Blister Lichen (Thalloidima sedifolium, previously Toninia sedifolia) is a rare terricolous lichen of open, bare calcareous and sandy soil, its pale, granular thallus and distinctive blue-grey, blister-like apothecia making it one of the more recognisable members of the internationally important Breckland soil-crust lichen community. In Britain, it is largely confined to the Breckland of Suffolk and Norfolk, where the warm, dry, continental-influenced climate and long tradition of open-ground management through rabbit grazing and disturbance have preserved the sparsely vegetated conditions it requires. Suffolk holds some of the most significant sites nationally, and the maintenance of open, undisturbed calcareous and sandy ground is fundamental to the survival of this species alongside the wider soil-crust lichen community for which the Breckland is celebrated. Image: © Aissa Djamel Filali, iNaturalist.

Find out more: iNaturalist, British Lichen Society