Rainforest Ants (Hymenoptera: Formicidae) at Eungella in the Clark Range

Burwell, C. J., & Nakamura, A. (2020)

Abstract

Here we provide a faunistic overview of the rainforest ant fauna of the Eungella region, located in the southern part of the Clarke Range in the Central Queensland Coast, Australia, based on systematic surveys spanning an elevational gradient from 200 to 1200 m asl. Ants were collected from a total of 34 sites located within bands of elevation of approximately 200, 400, 600, 800, 1000 and 1200 m asl. Surveys were conducted in March 2013 (20 sites), November 2013 and March–April 2014 (24 sites each), and ants were sampled using five methods: pitfall traps, leaf litter extracts, Malaise traps, spraying tree trunks with pyrethroid insecticide, and timed bouts of hand collecting during the day. In total we recorded 142 ant species (described species and morphospecies) from our systematic sampling and observed an additional species, the green tree ant Oecophylla smaragdina, at the lowest elevations but not on our survey sites. With the caveat of less sampling intensity at the lowest and highest elevations, species richness peaked at 600 m asl (89 species), declined monotonically with increasing and decreasing elevation, and was lowest at 1200 m asl (33 spp.). Ant species composition progressively changed with increasing elevation, but there appeared to be two gradients of change, one from 200–600 m asl and another from 800 to 1200 m asl. Differences between the lowland and upland faunas may be driven in part by a greater representation of tropical and arboreal-nesting species in the lowlands and a greater representation of subtropical species in the highlands. We briefly overview the Eungella ant fauna of each subfamily and make comparisons with ants collected from surveys along comparable elevational gradients at Lamington National Park in subtropical south-eastern Queensland, and Mt Lewis in the Wet Tropics bioregion of northern Queensland.