Lathrolestes ensator is a species of wasp in the family Ichneumonidae. it is a parasitoid of the apple sawfly Hoplocampa testudinea. Both insects are native to Europe, but the sawfly has been accidentally introduced into North America where it has become established.[1] The larvae of the sawfly tunnel into developing apple fruitlets which later fall to the ground, where the larvae continue their development. The wasp parasitises the larvae and has been released in North America as part of a biological control programme for the sawfly.[2]

Lathrolestes ensator
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Ichneumonidae
Genus: Lathrolestes
Species:
L. ensator
Binomial name
Lathrolestes ensator
(Brauns, 1898)

Ecology

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In a research study in the Netherlands, L. ensator was the only parasitoid of the apple sawfly larvae that was found, and the sawfly was the only host used by it. The wasp preferentially chose second instar larvae in which to lay eggs, and the spring emergence of the adult wasp usually synchronised with this stage of the host's life cycle. The female wasp produced around 150 eggs but did not actually oviposit as many as half of these.[3]

Use in biological control

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In Europe, the apple sawfly is part of the food web, but when it was accidentally introduced into North America, there were no natural enemies to control it and it caused much damage to the apple crop. In a classical biological control programme. L. ensator was released into Quebec between 1994 and 2001 and became established in the Frelighsburg area. Further work was undertaken between 2002 and 2015 to spread the parasite throughout eastern North America. This was done by collecting fallen fruitlets of apple trees in infected orchards in the Frelighsburg area, and scattering them in orchards in other parts of Quebec, Ontario, Nova Scotia and New Hampshire. As a result of this introduction, the wasp became established in three other parts of Quebec and in Hilton in Ontario.[4]

References

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  1. ^ Langor, David; Sweeney, Jon (2009). Ecological Impacts of Non-Native Invertebrates and Fungi on Terrestrial Ecosystems. Springer Science & Business Media. p. 14. ISBN 978-1-4020-9680-8.
  2. ^ "European apple sawfly". Ontario: Ministry of Agriculture, Food and Rural Affairs. Retrieved 14 May 2017.
  3. ^ Zijp, J.P.; Blommers, L.H.M. (2002). "Impact of the parasitoid Lathrolestes ensator (Hym., Ichneumonidae, Ctenopelmatinae) as antagonist of apple sawfly Hoplocampa testudinea (Hym., Tenthredinidae)". Journal of Applied Entomology. 126 (7–8): 366–377. doi:10.1046/j.1439-0418.2002.00666.x. S2CID 85031521.
  4. ^ Vincent, Charles; Appleby, Margaret; Eaton, Alan; Lasnier, Jacques (2016). "Dissemination of Lathrolestes ensator (Ichneumonidae), a larval parasite of the European Apple Sawfly, Hoplocampa testudinea (Tenthredinidae), in Eastern North America". Biological Control. 100: 1–6. Bibcode:2016BiolC.100....1V. doi:10.1016/j.biocontrol.2016.03.012. S2CID 86947092.