Hawaiian Pseudococcidae (Hemiptera): A Group That Perkins Missed

Abstract

Among the 16 or so recognized families of Coccoidea, only Pseudococcidae and the small, specialized Halimococcidae are represented in the endemic Hawaiian fauna. Why other large coccoid families failed to establish there is unknown. The endemic Pseudococcidae of Hawai'i currently include 31 described species in 13 genera. Ten genera are endemic. Around 40 undescribed endemic mealybug species belonging to both described and undescribed genera also are known. Perkins apparently collected no endemic mealybugs. Kirkaldy in Fauna Hawaiiensis listed the "Family Coccidae" (= Coccoidea) as absent from the endemic Hawaiian fauna. At least five or six, possibly more, prehistoric colonizations of Hawai'i by mealybugs were required to produce the existing fauna. Most of the endemic genera are so highly specialized that their relationships to extra-Hawaiian forms are obscure. However, some endemic species of Pseudococcus appear to be closely related to species in Australia and the Pacific islands. This conclusion is based primarily on similarities in male genitalia and secondarily on female morphology. Endemic Hawaiian mealybugs are often cryptic, occupying habitats such as plant galls, rolled leaves, under bark, and leaf sheaths of grasses. Those that occupy more exposed locations on foliage or twigs usually are cryptically colored or armed with large spines. These specialized habitats and morphologies appear to have evolved in response to pressure from predators.