Bionomics and Nest Structure of Pogonomyrmex ocddentalis (Hymenoptera: Formicidae)1

Abstract

Twenty colonies of Pogonomyrmex ocddentalis (Cresson) were excavated at Casper, Wyoming to determine the total number of ants occurring in colonies during the winter and to ascertain the location of the queen. An additional 13 colonies were excavated at Casper at the rate of 1 colony per month over an entire year to observe the effect of soil temperatures on the activities of this ant. The structure of each colony was mapped, and the location of seed chambers and amount of seed stored were determined. Inquilines associated with P. occidcntalis were the cetoniids Cremastocheilus knochi LeConte, C. saucia LeConte, and the tenebrionid Aracoschisus armatus Horn. The 2 last-mentioned species were collected from chambers containing the overwintering worker ants.