Farm Forestry New Zealand
PESTS AND DISEASES OF FORESTRY IN NEW ZEALAND
Gum tree weevil - Same insect, different name
Scion is the leading provider of forest-related knowledge in New Zealand
Formerly known as the Forest Research Institute, Scion has been a leader in research relating to forest health for over 50 years. The Rotorua-based Crown Research Institute continues to provide science that will protect all forests from damage caused by insect pests, pathogens and weeds. The information presented below arises from these research activities.
From Forest Health News No. 222, February 2012.
A very recently published paper by Mapondera et al (see below) means that the Australian gum tree weevil present in New Zealand now has different name. For years it has been referred to as Gonipterus scutellatus but it has now been determined that this is a misidentification. The species we have in New Zealand is Gonipterus platensis.
Apparently Gonipterus platensis is native to Tasmania and has also been introduced into southern South America (Argentina, Brazil, Chile), western North America (California, Hawaii) and western Europe (Portugal, Spain). The Gonipterus introduced into South Africa and Italy have in the past been referred to as G. scutellatus (and sometimes G. gibberus) are an undescribed species. There is some evidence that G. platensis is also present in South Africa.
Gonipterus was first recorded in New Zealand in 1890 in Wellington. It was first recorded as Gonipterus sp. and then was known as Gonipterus reticularis until 1925 when it was referred to as G. scutellatus. This determination was made at the Imperial Bureau of Entomology, London.
By the late 1920s Gonipterus was considered to be a serious enough pest of eucalypts in New Zealand that an egg parasitoid, Anaphes nitens (Pteromalidae), was introduced from Australia as a biological control agent. The initial consignment in 1927 was sent here by a South African entomologist who was sending parasitoids back to South Africa. Progeny of this importation did not establish and more were imported from Australia in 1929-30. By the mid 1930s the parasitoid was well established in North Island and in parts of the South Island. It is now known to occur throughout New Zealand. Gonipterus is well controlled by the parasitoid and is an excellent example of successful biological control.
Anaphes nitens has been introduced to various parts of the world to control Gonipterus with varying results. In the light of current knowledge this is not surprising because we now know that several species of Gonipterus have established in different parts of the world and in some cases there might not be a good match with the parasitoid and the host. Perhaps we were lucky in New Zealand because “our” Gonipterus comes from Tasmania but the parasitoid was obtained from mainland Australia.
This unravelling of the Gonipterus “scutellatus” complex is a very good example of the importance of taxonomy. It could result in improvements to biological control of Gonipterus in different parts of the world by better matching parasitoids. For example, trials are underway in Portugal using two Tasmanian species of Anaphes; “their” Gonipterus like “ours” came from Tasmania; i.e. it is G. platensis.
John Bain and Toni Withers
Reference:
Mapondera, T S; Burgess, T; Matsuki, M; Oberprieler, R G, 2012: Identification and molecular phylogenetics of the cryptic species of the Gonipterus scutellatus complex (Coleoptera: Curculionidae: Gonipterini). Australian Journal of Entomology. Article first published online: 1 FEB 2012. DOI: 10.1111/j.1440•6055.2011.00853.x
This information is intended for general interest only. It is not intended to be a substitute for specific specialist advice on any matter and should not be relied on for that purpose. Scion will not be liable for any direct, indirect, incidental, special, consequential or exemplary damages, loss of profits, or any other intangible losses that result from using the information provided on this site.
(Scion is the trading name of the New Zealand Forest Research Institute Limited.)
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