After notice of the above presentation was posted on Conch-L, the following comments were provided (thanks to all in the Conch-L community for providing additional, first-hand information to expand all our knowledge).

6/27/14 Moshe Erlendur wrote:

"You can add Iceland to your Nucella lapillus distribution map. I have personally collected it in the west & south where it is abundant and quite variable.
According to Thorson (1941) and Óskarsson (1962, 1982) it can also be found along the northern coast and perhaps in the east as well."

6/27/14 Steve Rosenthal reported a 2010 email from Zvia Mienis. Zvia had reported:

"In the collection of the Hebrew University of Jerusalem we have the following large specimens of Nucella lapillus:

63.8 mm Great Britain, Kent, Sandwich leg. J. Dalgleish (a heavy shell)

62.8 mm Great Britain, Dorset, Savanage leg. G.L. Wilkins (a very heavy shell)

57.0 mm Great Britain, Minehead, leg. Fowler (a light shell)"