Abstract The existence of three chemotypes of Coridothymus capitatus in Israelâa thymol-type, a carvacrol-type and a mixed-chemotype which contained thymol and carvacrol in the ratio about 1:2âwas confirmed. A detailed composition of the volatiles of C. capitatus was studied by GC/MS and, excluding thymol/carvacrol ratio, the components of the oils were found to be nearly identical. With the exception of biosynthetically interrelated Î³-terpinene, p-cymene, thymol and carvacrol, the major volatile constituents of C. capitatus were found to be Î²-caryophyllene, caryophyllene oxide, thymohydroquinone and thymoquinone.