A structurally new acylated anthocyanin was isolated from the pale-brownish red flowers of a duskish-2 mutant in the Japanese morning glory (Ipomoea nil or Pharbitis nil) as a major pigment together with a known anthocyanin. The new pigment was determined as pelargonidin 3-O-[2-O-(6-O(trans-3-O-(beta-glucopyranosyl)caffeoyl)-beta-glucopyranosyl)-beta-glucopyranoside], and the known anthocyanin was identified to be pelargonidin 3-sophoroside.