Biological traits and field distribution of introduced Arhopalus species in Central Argentina

Abstract

Arhopalus rusticus rusticus and Arhopalus syriacus (Coleoptera: Cerambycidae) are exotic forestry pests that coexist in Córdoba (Argentina). To contribute to forest management strategies, we examined how their emergence, development, and abundance affect the sex ratio. We found a dispersal sex ratio of 0.5:0.5 (males:females) in both species. The birth sex ratio was 0.5:0.5 in A. syriacus and 0.6:0.4 in A. r. rusticus. In rearing experiments, A. r. rusticus had larger individuals, with several larval instars and high survival ratio, but developmental time was shorter in A. syriacus. We found an asymmetric distribution, but there are indications that the range of A. syriacus is advancing northward.