Pheidole rhea
Arizona, USA

photograph © Alex Wild 2005

Major and minor workers of North America's largest Pheidole species, P. rhea.  The giant heads of the major workers are used for milling seeds.  These ants are sisters and are genetically very similar to each other, the differences result from alternate developmental pathways.

USA AZ Cochise Co.:  10 km NNW Portal 
31º59'N 109º12'W 1500m.
Chiricahua desert, limestone outcrop.
8.viii.2005   #AW2653, voucher specimens deposited at ALWC.

This image is copyrighted by the photographer and cannot be used without permission. To obtain permission to use this image, please email Alex Wild. (alwild (at)  Most of the photographs on are reduced from their original size and compressed for more efficient web transmission.  In some cases, higher quality versions are available.

This image was captured with a Canon EOS D60, with a Canon 65/2.8 MPE 1-5x Macro lens.