New Zealand Entomologist (2008) 31(1): 41–46
©New Zealand Entomological Society, Inc.

Research article
Observations on the ecology and behaviour of Ctenognathus novaezelandiae (Fairmaire) (Coleoptera: Carabidae)

Bruce A Philip ¹ and Elisabeth P. J. Burgess <sup>*2

1</sup> MAF Biosecurity New Zealand, P. O. Box 2526, Wellington, New Zealand
² The Horticulture and Food Research Institute of New Zealand Ltd, Private Bag 92 169, Auckland, New Zealand. E-mail: eburgess@hortresearch.co.nz
^*Corresponding author.

Abstract: Adults of the carabid Ctenognathus novaezelandiae (Fairmaire) were collected from Woodhill pine forest north of Auckland between 2000 and 2003. Although the beetles were collected specifically for experimental purposes, we present incidental data and observations on C. novaezelandiae ecology and behaviour. Adults, at least in spring and summer, are gregarious. The sex ratio of those caught by searching forest fl oor litter heavily favoured males, while females dominated pitfall trap collections. Ctenognathus novaezelandiae appears to be univoltine in Auckland. Adults emerged in spring, were essentially inactive over summer, and bred in autumn and winter. Larvae were present during autumn and winter, and adult numbers decreased from about mid-winter onwards. While this pattern fits the classic Northern Hemisphere model of autumn-breeding carabids, it is different from that of other New Zealand carabids studied, adults of which have a prolonged period of activity between spring and autumn with one or two peaks of activity, and are mostly inactive over winter.

Keywords: carabid beetle; New Zealand; endemic; pine forest; seasonality