Embola powelli is another summer species, with only two silver markings on the inner forewing, not three, and the innermost one usually forms a transverse stripe.
Hsu, Yu-Feng & J.A. Powell, 2004. Phylogenetic Relationships within Heliodinidae and Systematics of Moths Formerly Assigned to Heliodines Stainton (Lepidoptera: Yponomeutoidea). University of California Publications in Entomology, 124: 64-67 (PDF)
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