Gonipterus (Coleoptera: Curculionidae) in subtropical Australia: host associations and natural enemies

Abstract

Gonipterus is a genus of defoliating weevils that causes significant impact in commercially grown eucalypts in their native range in southern Australia and as invasive pests in Western Australia and several countries overseas. The diversity of species in this genus is still in the process of discovery, and in subtropical Australia, its diversity and ecological parameters are largely unknown. We surveyed Gonipterus phenology, species composition and trophic associations in South East Queensland, where little has been recorded about this genus. Surveys were conducted once a month in a non‐commercial plantation of native eucalypts, where three species of trees were sampled regularly and others checked on an ad hoc basis. On each sampling occasion, adult weevils, larvae and egg capsules were collected, adults identified, larvae reared and egg capsules individualized in small containers for emergence of larvae and parasitoids. Two peaks of egg‐laying occurred, whereas numbers of adults and larvae had only one peak each. Six species of Gonipterus were collected: two described but in need of revision, two undescribed but previously recognized and two undescribed and hitherto unrecognized, each with a different pattern of host–tree association. Three egg‐parasitoid species, Anaphes nitens, Centrodora damoni and Euderus sp. were reared from egg capsules, varying in prevalence according to the tree species from which the eggs were collected.

Ovi-protective mothers: exploring the proteomic profile of weevil (Gonipterus) egg capsules

“…Another interesting finding was the annotation of G_21 with an AgSP-1 arylphorin from Anthonomus grandis (Coleoptera: Curculionidae), which is an indicator of diapause in this species since it negatively correlates with vitellogenin ( Lewis et al., 2002 ). Quantifying the abundance of these proteins over time may elucidate any similar function in Gonipterus : females have lengthy non-egg-laying periods ( Souza et al., 2021 ) that may be physiologically analogous to diapause. Among the proteins found in both egg capsules and frass was the protein encoded by G_40 (highly expressed in reproductive tissue).…”

Distribution of Gonipterus Species and Their Egg Parasitoids in Australia: Implications for Biological Control

“…In this study, two collection trips were made at the end and beginning of summer in two consecutive years. Additional surveys in Queensland were undertaken by Souza et al [65]. A temporal sampling strategy focused on specific regions, climatically matched with the target release area, will contribute to detecting the presence of Gonipterus and parasitoid species that were not abundant at the time collections were performed in the present study.…”

Ecosystem-Scale Distribution and Phenology of Adult Gonipterini Weevils Associated with Eucalyptus populnea in Central Queensland, Australia

“…Both the larvae and adults from this tribe are generally found on eucalyptus trees, where they feed upon the leaves. Several species of Gonipterus have become international pests of Eucalyptus plantations [1,2], including in New Zealand, South America and South Africa [3]. Consequently, many studies on these genera have focused on the discovery of parasitoids for use as biocontrol agents [4], and clarifying the identification and taxonomy of cryptic species [2].…”

“…However, despite the considerable significance of this tribe, there have been limited studies on the interactions and phenology of Gonipterini species in their natural habitat. Recent studies have investigated the phenology, trophic associations and parasitoids of Gonipterus species from Tasmania [6] and subtropical Australia [3], but did not consider Oxyops species. Consequently, this study aimed to investigate the phenology and associ-ations between the adult weevils of two species of Oxyops and two species of Gonipterus from Central Queensland, Australia.…”