Syncesia myrticola parasite de Roccella phycopsis

    Like Lecanographa grumulosa on the old, somewhat alkaline walls, it appears that Syncesia myrticola is a particularly active parasite of the lichens that colonize the dry overhangs of coastal siliceous rocks and that Roccella phycopsis is a host of choice. Here are some photographs which illustrate what we think to be a parasitism with at the beginning destruction of the host (the 2 thalli being mixed, the colored chemical reactions are those of the host and the parasite) and at the end Syncesia myrticola regains a life independent (characterized by its significant color chemical reactions).