Photoactivated miticidal and insecticidal ethynylthiazoles

A photoactive acaricidal ethynylthiazole of formula I or II:

• ##STR4## in which, when said ethynylthiazole is of formula I, (a) R.sup.1 is phenyl or phenyl substituted with a substituent selected from lower alkyl, halogen and lower haloalkyl;
• R.sup.2 is phenyl, phenyl substituted with a substituent selected from lower alkyl, halogen, lower haloalkyl and --OCF.sub.2 O-- bridging adjacent ring carbon atoms, thienyl, thienyl substituted with lower alkyl, halogen or lower alkoxycarbonyl;
• and
• R.sup.3 is hydrogen, lower alkyl, phenyl or methylphenyl;
• or
• (b) R.sup.1 is selected from the group consisting of methylthienyl, and C.sub.4 -C.sub.6 alkyl;
• R.sup.2 is phenyl or phenyl substituted with a substituent selected from halogen, lower haloalkyl, and --OCF.sub.2 O-- bridging adjacent ring carbon atoms;
• R.sup.3 is hydrogen;
• or when said compound is of formula II, R.sup.1 is phenyl, and
• R.sup.2 is phenyl, thienyl, or phenyl substituted with a substituent selected from lower alkyl and halogen.