Amazing! Would appear to be family Apocynaceae (including former Asclepiadaceae) - note leaves in very regular whorls of 3 at right of your picture. That said, I have never seen anything like it.
That looks like it. In fact my first thought on looking at the 'flowers' in Nadia's photo was a Euphorbia, because of the resemblance to E. misera, which I have seen myself in Baja. The whorled leaves threw me off, together with their shape and texture. If a good sharp closeup photo had been available I would have known.