Inheritance of the two dorsal colour/pattern phenotypes in New Zealand populations of the polymorphic meadow spittlebug Philaenus spumarius (L.) (Homoptera: Cercopidae)

The meadow spittlebug Philaenus spumarius (L.) exhibits a striking dorsal colour/pattern polymorphism throughout its distribution in the Holarctic region. At least 16 different dorsal colour morphs have been reported from several European and North American populations. It is also abundant in New Zealand, but only two different forms-flavicollis (FLA) and typicus (TYP)-are expressed by the two different alleles, F and t respectively. This paper describes the laboratory crossing experiments performed on the inheritance of the FLA and TYP phenotypes in New Zealand populations of Philaenus spumarius. A total of 431 progeny from 25 successful crosses using New Zealand material clearly show that FLA is dominant over TYP in both sexes, as established in British P, spumarius populations. But the model of inheritance found in New Zealand populations of P. spumarus differs from that in previously studied Fennoscandian populations, where there is a reversal dominance in the sexes involving FLA and TYP.