My first reaction to seeing this plant was to think it was a Canary island version of Smyrnium olusatrum (Alexanders) which also flowers in early Spring and has similar yellow umbelliferous flowers. The thick curled leaves are completely different though and the Spanish call this plant Lechuga de mar: Lettuce of the Sea.

Coastal path from Puerto de la Cruz to Cafe Paradiso, Tenerife, 11th February 2009

Added 12th March 2009, updated 1st March 2010, updated 26th June 2015