How Blister Beetle Nest Parasites Cooperate to Mimic the Sex Pheromone of a Solitary Bee
April 3, 2012
|Leslie Saul-Gershenz concentrates her research on how blister beetle nest parasites cooperate to mimic the sex pheromone of a solitary bee. (Photo by Kathy Keatley Garvey)|
DAVIS--UC Davis evolutionary ecologist Leslie Saul-Gershenz and her colleagues examine how blister beetle nest parasites cooperate to mimic the sex pheromone of a solitary bee in peer-reviewed research published in the April edition of the Mojave National Preserve Science News.
Saul-Gershenz, a graduate student in the Neal Williams lab, UC Davis Department of Entomology, researches a solitary ground-nesting bee, Habropoda pallida and its nest parasite, a blister beetle, Meloe franciscanus, found in the Mojave National Preserve.
She is the lead author of “Blister Beetle Nest Parasites Cooperate to Mimic the Sex Pheromone of the Solitary Bee Habropoda pallida (Hymenoptera: Apidae)," co-authored by professor Jocelyn G. Millar and staff research associate J. Steven McElfresh, both of UC Riverside.
The solitary bee is the first native bee to emerge in the spring on the Kelso Dunes in the Mojave National Preserve, said Saul-Gershenz. “The adult beetles emerge on the dunes in the winter months at Kelso Dunes and feed exclusively on the leaves of Astragalus lentiginosus, which leafs out in January."
The bee's emergence is generally synchronized with the onset of blooms of the Borrego milkvetch, which is the sole host plant of adults of the blister beetle at Kelso Dunes.
Saul-Gershenz said the larvae of the parasitic blister beetle produce a chemical cue or a pheromone similar to that of a female solitary bee to lure males to the larval aggregation. The larvae attach to the male bee and then transfer to the female during mating. The end result: the larvae wind up in the nest of a female bee, where they eat the nest provisions and likely the host egg.
|Side view of digger bee, Habropoda pallida, foraging on Borrego milkvetch (Astragalus lentiginosus var. borreganus). Note the parasitic larvae of the blister beetle (Meloe franciscanus). (Photo by Leslie Saul-Gershenz)|
“The Mojave Desert ecosystem supports 689 species of bees, which is the highest bee diversity in North America,” Saul-Gershenz noted. The wide variety of insects endemic, or known only to that area, include a fly, scarabs, crickets, weevils, a bee, aphid wasp and scores yet to be described.
The April edition is devoted to scientific research under way in the preserve. The newsletter is geared for National Park Service employees, the scientific community, and the general public.
Mojave National Preserve science advisor Debra Hughson wrote in a sidebar that “The Mojave Desert is internationally known as a place to conduct scientific research on desert ecosystems. In fact Mojave National Preserve was designated in part to ‘retain and enhance opportunities for scientific research in undisturbed ecosystems’ as stated in the California Desert Protection Act of 1994. Much of this research is conducted through the Sweeney Granite Mountains Desert Research Center, part of the University of California Natural Reserve System, and the Desert Studies Center, operated by the California Desert Studies Consortium of California State Universities. Both are located in the Preserve.
Last year Saul-Gershenz, Williams and Millar received a grant to study digger bee ecology and conservation. They're working with SaveNature.Org, which Saul-Gershenz co-founded. The relationship between the bee and the blister beetle is part of the research.
--Kathy Keatley Garvey
UC Davis Department of Entomology