The parasitoid guild of larvae of Chrysophtharta agricola Chapuis (Coleoptera: Chrysomelidae) in Tasmania, with notes on biology and a description of a new genus and species of tachinid fly

Abstract

The taxonomic status of the parasitoid guild associated with the larvae of Southern Eucalypt Beetle (Chrysophtharta agricola Chapuis) in Tasmania is discussed. The primary larval parasitoid complex comprised the tachinid flies Balde striatum gen. n., sp. n. and Paropsivora australis (Macquart) (Diptera: Tachinidae: Goniinae: Blondeliini), and Eadya paropsidis Huddleston & Short (Hymenoptera: Braconidae), while the hymenopteran hyperparasitoids included Perilampus tasmanicus (Cameron) (Perilampidae), Mesochorus sp. (Ichneumonidae) and possibly Meteorus sp. (Braconidae). Keys are provided to the three adult primary parasitoids and two adult hyperparasitoids, and to the pupae of primary parasitoids. Balde striatum gen. n., sp. n. is described, and P. australis is redescribed. Brief notes on biology are included.

Sex‐biased parasitism of adult spring beetles, Heteronyx dimidiata and Heteronyx crinitus, by Tachinidae in Eucalyptus nitens plantations in Australia

“…In Australia, the Blondeliini are recorded as parasitoids of the larvae and adults of species belonging to other Coleopteran families, such as the Chrysomelidae and Curculionidae, including the forestry pests Paropsis spp. and Gonipterus scutellatus (Gyllenhal, 1833) (Cantrell ; Rice ; Rice & Allen ), which were also common in E. nitens plantations on the Surrey Hills estate. Worldwide, the tribe Blondeliini is known to parasitise scarabs, e.g.…”

Options for managing chrysomelid leaf beetles in Australian eucalypt plantations: reducing the chemical footprint

“…In their natural Australian distributions, natural enemies are very important for maintaining populations of eucalyptus leaf beetles below damaging levels most of the time. Predation during the egg and first‐instar larval stages and some parasitism of eggs and larvae account for up to 95% of natural mortality of P. bimaculata and P. agricola (de Little et al ., ; Nahrung & Allen, ; Rice, ). However, even this level of natural control does not prevent periodic, invasions of plantations by large leaf beetle populations that cause heavy defoliation of their eucalypt hosts.…”

Temperature and developmental interactions in a multitrophic parasitoid guild

“…(Nahrung 2004). P. agricola larvae are present on foliage from mid spring to early autumn where they are parasitised by two tachinids from the tribe Blondeliini, Paropsivora australis and Balde striatum and a braconid wasp Eadya paropsidis (Rice 2005a). The tachinid B. striatum is itself hyperparasitised by an ichneumonid wasp, Mesochorus sp.…”

“…The tachinid fly, P. australis , is a medium sized tachinid fly that adheres large white eggs on the integument of its host that hatch and burrow into the haemocoel of the host. The larvae remain just under the host's integument and retain contact with the atmosphere via a respiratory funnel (Rice 2005a). P. australis has a preference for parasitising fourth‐instar hosts, emerges from the pre‐pupal stage, and undergoes at least two generations per year.…”

“…B. striatum is a smaller tachinid fly that deposits first‐instar larvae onto the underside of its host, preferentially parasitises first‐ and second‐instar hosts, undergoes more than one generation per year, and emerges from late third and fourth‐instar hosts (Rice 2005b). P. australis is also recorded from the host Parposisterna (= Chrysophtharta ) bimaculata (Olivier), and there are numerous rearing records for unidentified species of Paropsivora from paropsine leaf beetle larvae but it is not clear if they are P. australis (Rice 2005a). Alternative hosts for B. striatum consist of a single rearing from Acacicola orphana (Erichson) (Rice 2005a).…”