Jorun, the bottom one looked to me rather stapeliad-ish, and the middle one rather asclepiadish, but I don't really have a clue. So I asked Chris Gardner - who will be taking a number of us from the Mediterranean Garden Society to Tenerife and Gomera next week - if he could advise. He says the first picture is Ononis angustissima, and thinks that the last two are probably members of the Chenopodiaceae, which he says the Canaries are rich in them.
But he adds that the large number of introduced species adds to identification problems there.
I hope that helps.