By Arthur V. Evans
One of the first scarab beetles to cross my path here in Virginia every spring is the bumble scarab or bumblebee flower beetle, Euphoria inda (Linnaeus). I have also found these beetles burrowing into thistle flowers in the Chiricahua Mountains of southeastern Arizona and flying in a field next to a parking lot at the Butterfly Pavilion in Westminster, Colorado. These beetles feed on various flowers, ripe fruits, and plant sap. They are sometimes found clustering on sap flows on the trunks of trees, or on the stalks of sunflowers, corn, and okra. Bumble scarabs are distributed from Ontario and Quebec south to Florida, west to the Rocky Mountains and southeastern Arizona, and south to Mexico.
Overwintering adults emerge from their hiding places on the first warm days of late winter and early spring and buzz noisily as they fly low over dry leaves, edges of haystacks, compost piles, manure, and other plant debris. These accumulations of plant materials, along with rotten wood and the thatched nests of Formica ants, serve as their breeding grounds. The larvae pupate in earthen pupal cases in summer. Adults emerge briefly in late summer to feed and before settling in for the winter.
Years ago, while I was a doctoral student at the University of Pretoria, I traveled to Cape Town to spend a week at the South African Museum. There I had the opportunity to study the type specimens of scarab beetles described in the late nineteenth and early twentieth centuries by a former director of the museum, Louis A. Péringuey (1855-1924). Although I was primarily interested in studying melolonthine scarabs, I took the opportunity to look at the types of many scarab species in several subfamilies, especially several monotypic African scarab genera, that is genera that each include only one species.
Péringuey discovered a single specimen of a cetoniine scarab with a label indicating that it was collected in the town of Ladysmith in the Cape Province. He considered this unique specimen to represent an undescribed genus and species from the African continent. In 1907, he named this new species Goraqua smithsana. Curiously, this species was never again collected in South Africa and it remained known only from the type specimen for more than 80 years.
I examined Péringuey’s type specimen of G. smithsana and immediately recognized it as Euphoria inda, which was first described as Scarabaeus indus by Carolus Linnaeus in 1758. The single female specimen that Peringuey used as a name holder for his new genus and species had been mislabeled. Because our system of zoological nomenclature is based on the concept of priority, the older name proposed for this species by Linnaeus takes precedence over subsequent names given to the same species. In the jargon of taxonomy, the name Goraqua smithsana Péringuey is a junior synonym of what is now known as Euphoria inda (Linnaeus). Such changes are not instantaneous and must be published in the scientific literature before they are recognized by the greater taxonomic community.
I shared my discovery with Erik Holm at the University of Pretoria. Holm was involved in a series of projects to document the cetoniine scarabs of Subsaharan Africa, of which Goraqua smithsana was a part. He published the synonymy in 1989.
Holm, E. 1989. Synonymic notes on the African Cetoniinae III: Goraqua smithsana Péringuey = Euphoria inda (L.) (Coleoptera, Scarabaeidae). Cimbebasia 10: 148.
Iziko South African Museum. http://www.iziko.org.za/sam/ (accessed 20 March 2011)
Péringuey, L.A. 1907. Descriptive catalogue of the Coleoptera of South Africa (Lucanidae and Scarabaeidae). Tribe Cetonini. Transactions South African Philosophical Society 13; 1-546.
Ratcliffe, B.C. and M.J. Paulsen. 2008. The scarabaeoid beetles of Nebraska. Bulletin of the University of Nebraska State Museum 22: 568 pp.
Scarab workers world directory. http://www.unl.edu/museum/research/entomology/workers/EHolm.htm (accessed 20 March 2011)
© 2011, Arthur V. Evans