A good friend mio had the gentility to bring shells to me of memory of a trip to the canary islands, in the stores said to him that the units were of the same island, evidently with commercial interests since both surely come from the ocean indic, but with himself not to classify them Please they can help me? The photographies in: http://es.geocities.com/malacologia/identificar/trochus.jpg http://es.geocities.com/malacologia/identificar/murex.jpg