The importance of ants in cave ecology, with new records and behavioral observations of ants in Arizona caves

Abstract

The importance of ants as elements in cave ecology has been mostly unrecognized. A global list of ant species recorded from caves, compiled from a review of existing literature, is presented. This paper also reviews what is currently known about ants occurring in Arizona (USA) caves. The diversity and distribution represented in these records suggests ants are relatively common cave visitors (trogloxenes). A general utilization of caves by ants within both temperate and tropical latitudes may be inferred from this combined evidence. Observations of ant behavior in Arizona caves demonstrate a low level and sporadic, but persistent, use of these habitats and their contained resources by individual ant colonies. Documentation of Neivamyrmex sp. preying on cave-inhabiting arthropods is reported here for the first time. Observations of hypogeic army ants in caves suggests they may not penetrate to great vertical depth in search of prey, but can be persistent occupants in relatively shallow, horizontal sections of caves where they may prey on endemic cave animals. First cave records for ten ant species are reported from Arizona caves. These include two species of Neivamyrmex (N. nigrescens Cresson and Neivamyrmex sp.; Formicidae: Dorylinae), four myrmicines (Pheidole portalensis Wilson, Pheidole cf. porcula Wheeler, Solenopsis aurea Wheeler and Stenamma sp. Westwood), one dolichoderine (Forelius keiferi Wheeler) and three formicines (Lasius arizonicus Wheeler, L. sitiens Wilson, and Camponotus sp. Mayr).