The Effect of Clutch Size and Ant Attendance on Egg Guarding by Entylia Bactriana (Homoptera: Membracidae)

Subsocial behavior is postovipositional parental care that promotes the development and survival of offspring. Subsociality is particularly common in the Membracidae (Homoptera) in which the females of many species guard eggs and nymphs from predators and parasites (Eickwort 198 1, Hinton 198 1, Tallamy and Wood 1986, Eberhard 1986). A number of treehopper species also interact with ant mutualists. Treehoppers provide ants with a nutritional resource in the form of honeydew and ants provide treehoppers protection from natural enemies (Way 1963). Since the survival of offspring of many treehoppers is contingent upon protection by attendant ants (Hinton 1977, Wood 1977, 1979, 1982a, 1982b, McEvoy 1979, Fritz 1982, 1983, Bristow 1983, 1984) selection should favor females that increase the probability that their offspring will be located and tended by ants. A number of studies have documented the influence of ants on the maternal protection of young by subsocial treehoppers. For example, female Publilia recticulata Van Duzee desert nymphs after their offspring are located by ants. By transferring protection of offspring to ants, females may produce additional clutches (Bristow 1983, 1984). Similarly, tenure with nymphs is longer for P. concava females that are not ant attended (McEvoy 1979). In contrast, females of a closely related species, Entylia bactriana Germar, remain with eggs (Olmstead 1984) and nymphs (Wood 1977) longer when ant attended. However, none of the above studies examined the variation in protection of eggs and nymphs throughout the