• Calicium lenticulare Ach.
Calicium lenticulare
Click on map to open large map in new window
(Map updated: 11 August 2009)

This humidity-tolerant ‘pin-head’ lichen grows on the wood of decaying stumps. It has a granular, greenish-grey thallus but, most importantly, has long stalks which, when squashed in iodine, turn dark blue. It is a reaction unique to this species. The discs, which are shaped like an inverted traffic cone, have a reddish-brown tinge and a distinctive white dusting on the lower surface of the head. In Ireland, it is known only from County Kerry.

Key characteristics

  • Discs, reddish brown, inverted cone-shaped with white pruina
  • Stalks, dark blue in iodine squash; decaying stumps in humid woods.

Original text submitted by Vince J. Giavarini

 Simms, M. J., (2016). Calicium lenticulare Ach.. [In] LichenIreland. Accessed on 2020-09-19.