Maltawildplants.com is now considered an online flora of the Maltese islands, portraying more than 900 species of plants found in Maltese habitats. It harbours a forum created in 2005 were memberes discuss topics about the Maltese flora and ID of plants.
Very interesting photographs. I've seen LCL samples along the southern rdum of Malta absolutely riddled with this species' tubes. Also look out for Strombus casts which are also very commonly associated with Kuphus' presence.