Variation in egg numbers of the meadow spittlebug <i>Philaenus spumarius</i> (L.) associated with particular dorsal colour phenotypic groups among New Zealand, Turkish and Welsh populations

Detailed egg number variations for the polymorphic meadow spittlebug Philaenus spumarius (L.) that were obtained from continuous mass breeding experiments in fully laboratory conditions are reported for the first time. Genetic crossing experiments with certain colour/pattern phenotypes were set up using unmated virgin insects. Three generations were reared during the three-year period of the experiments. A total of 21,213 eggs were produced through 247 pairings. The general median number of eggs per pairing was 76. Egg numbers for the insects from New Zealand, Türkiye and Wales (UK) were comparable. Although the maximum number of 378 eggs was produced by a Typicus phenotype from Türkiye, the medians showed no sign of statistical differences among the three populations. However, the median number of eggs among the F1, F2 and F3 generations were different. The median test applies to the Wales data regarding the combined egg numbers of Melanic, Typicus and Trilineatus groups of phenotypes. The Melanic group of females produced more eggs (81) than Typicus (42) and Trilineatus (72), although with no statistically significant differences. The methods used allow for the maintenance of P . spumarius as a stock for consecutive overlapping generations, which may facilitate the management of future ecological and evolutionary investigations in this spittlebug as a dependable laboratory model organism. The results also will contribute to the debates and implications for breeding studies of P . spumarius in the field of population ecology.