Studies of Ants and Ant Guests at the Idaho National Laboratory Site
Investigators and Affiliations
William H. Clark, Orma J. Smith Museum of Natural History, The College of Idaho, Caldwell, Idaho
Funding is by the principal investigator with some assistance from and collaboration with the Orma J. Smith Museum of Natural History.
Background: Clark and Blom (2007) reported the first comprehensive annotated checklist of ants at the INL Site. This publication gives a starting point for additional research relating to ants, their natural history and ecology, and ant guests at INL Site. Ant guests (myrmecophiles) are organisms that live in close association with ants. These are generally mutualistic associations, but may also be commensal or parasitic.
Objectives: Immediate objectives are to locate living larvae of the ant guest beetle (Gonasida elata) (Coleoptera: Tenebrionidae) within nests of the harvester ant (Pogonomyrmex salinus) (Hymenoptera: Formicidae). These beetles have been documented from the harvester ant nests here in the past by Clark and Blom (unpublished data), but the larvae have not been previously described. Fresh larvae are needed for scanning electron microscopy (SEM) to provide for a proper description of these organisms. The overall objective will be to document the interaction of this beetle with the ants.
Other observations on additional ant guests will be made as they are encountered. Information relating to the ants of INL Site will be documented as possible.
Accomplishments through 2012: During the fall of 2011, 100 nests of the harvester ant (Pogonomyrmex salinus) were selected and marked along Road T-17 near Circular Butte (Figure 1). These nests were then surveyed by INL archaeologists for cultural resources and approval was given for excavation of nests as needed. A total of 10 percent of the nests were excavated during late 2011 and no Gonasida elata were found. Additional nests were excavated during the fall of 2012 and again no Gonasida elata were found. Searches will continue, perhaps during other seasons of the year.
Figure 1. Nest of Pogonomyrmex salinus (Hymenoptera: Formicidae) marked for future study. Nest near Circular Butte, November 2011, W.H. Clark photo. Ant mound is approximately 0.75 m diameter.
Results: Two ant guest taxa; an ant beetle (Coleoptera: Tenebrionidae: Araeoschizus sp.) (Figure 2) and a Jerusalem cricket (Orthoptera: Stenopelmatidae, Stenopelmatus) were found at the INL Site. The Stenopelmatus is likely also a species that has not been previously described. Both taxa will require more study during future visits to the INL Site.
Figure 2. Araeoschizus (Coleoptera: Tenebrionidae) found in a Pogonomyrmex salinus nest. Nest near Circular Butte, November 2011, W.H. Clark photo. Beetle is approximately 4 mm in length.
Plans for Continuation: Field research will continue into the foreseeable future.
Publications, Theses, Reports:The project is still in the field data collection phase and no publications have been prepared.