ABSTRACT
Within the Scarabaeoidea there is a disparity in the knowledge between less speciose basal lineages and the more speciose groups of “higher” Scarabaeidae. For example, the family Trogidae includes approximately 300 species in four genera. Excellent revisionary, larval, and phylogenetic studies are available for this group (Baker 1968; Scholtz 1982, 1986, 1990, 1991, 1993; Scholtz and Peck 1990). Excellent monographs are also available for the approximately 600 species of Geotrupidae (Howden 1955, 1964, 1979, 1985a-b, 1992; Howden and Cooper 1977; Howden and Martínez 1978) and the Trogidae (Vaurie 1955), and these will provide the foundation for addressing relationships within this group. In comparison, the family Scarabaeidae (sensu Lawrence and Newton 1995) includes approximately 91% of the species (ca 27,800) of Scarabaeoidea. Within the Scarabaeidae, approximately 21,000 species are in the subfamilies Melolonthinae, Dynastinae, Rutelinae, and Cetoniinae (the “higher” scarabs). Only a few phylogenetic analyses have addressed relationships of pleurostict subtribes, genera, or species (Ratcliffe 1976; Ratcliffe and Deloya 1992; Jameson 1990, 1996, 1998; Jameson et al. 1994; Krell 1993), and only one analysis has been conducted to address tribal or subfamilial relationships (Browne and Scholtz 1999).
