Development and feeding of Tetraphleps galchanoides, a predator of the hemlock woolly adelgid

Abstract

Tetraphleps galchanoides Ghauri (Hemiptera: Anthocoridae) nymphs were collected from hemlock woolly adelgid (HWA) Adelges tsugae Annand (Hemiptera: Adelgidae) infested Tsuga sp. in Baoxing, Sichuan, China. First and second stage nymphs collected from foliage shipped from China; were reared to adults and tested for feeding rates and host preferences. They were reared at 5, 8, 12, and 15 ± 1°C , respectively, in the quarantine laboratory at Virginia Polytechnic Institute and State University. At 8°C, development time was 15, 20, and 40 days for the N-III, IV, and V nymphal stages, respectively. Adult males lived 83 days with a range of 21À147 days. A single adult female lived for 21 days. At 5°C, second stage T. galchanoides nymphs consumed 0.8 HWA nymphs per day, and 2.0 HWA nymphs per day at the N-V stage. At 8°C, consumption of HWA nymphs ranged from 1.3 to 3.4 nymphs per day for the N-III to N-V stages, respectively. Adult T. galchanoides consumed more HWA eggs than HWA adults, pine bark adelgid (PBA) Pineus strobi (Hartig) (Hemiptera: Adelgidae) adults, and eggs in no-choice tests. In choice tests with HWA eggs and PBA eggs, more HWA eggs were eaten. Adult and nymph body measurements are presented for determination of nymphal instars.

Host Range of <I>Laricobius osakensis</I> (Coleoptera: Derodontidae), a New Biological Control Agent of Hemlock Woolly Adelgid (Hemiptera: Adelgidae)

“…Foreign exploration continues to Þnd new natural enemies to augment the current assemblage of natural enemies being released (McAvoy et al 2007, Kohler et al 2008. Laricobius osakensis Montgomery and Shiyake (Montgomery et al 2011) was discovered in May 2005 in association with A. tsugae on T. seiboldii saplings in Japan.…”