An Aptera and its Abnormal Offspring Found in a Gall of Pemphigus dorocola (Homoptera, Aphidoidea)

Host-alternating species of the genus Pemphigus usually produce no apterae in their galls. An aptera, which may have been produced through a mutation, was found from a gall of Pemphigus dorocola. Some of its offspring (3rd-and 4th-instar immatures) had characters of the root generations or intermediate characters between the gall and root generations. These abnormal aphids are described, and their implication for the origin of monoecious life cycles is discussed.