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Species Caliroa cerasi - Pear Slug Sawfly

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Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hymenoptera (Ants, Bees, Wasps and Sawflies)
No Taxon ("Symphyta" - Sawflies, Horntails, and Wood Wasps)
Family Tenthredinidae (Common Sawflies)
Subfamily Heterarthrinae
Tribe Caliroini
Genus Caliroa
Species cerasi (Pear Slug Sawfly)
Other Common Names
Cherry Sawfly, Cherry Slug, Cherry Slug Sawfly, Pear Sawfly, Pear Slug Sawfly, Pear & Cherry Slugworm
Explanation of Names
Caliroa cerasi (Linnaeus 1758)
adult 4-6 mm, larva up to 11 mm(1)(2)
Native to Europe & w. Asia, adventive on all other continents(1)(3); in NA, widespread, mostly in n. US and so. Canada (map)(4)
In Canada adults emerge and fly in mid-June to late July, elsewhere as early as mid-May(5)
polyphagous on Rosaceae(3)
Feeds on cherry, pear, hawthorn, plum, quince, mountain ash, black cherry, shadbush(6)
Life Cycle
Parthenogenetic (males unknown in NA, rare in Europe), usually bivoltine in NA(2)
Overwinter in earthen cells or in cocoons composed of grains of soil held together by a substance secreted by the larvae. Pupation occurs in June.(6)
Eggs are laid singly in small semi-circular slits cut in the leaf tissue. The larvae feed mostly from the upper surface of the leaf, eating the parenchyma only. Full-grown larvae drop to the ground and form cells in the soil for pupation.(6)
Two generations per year.(6)
larvae feed on upper surface of leaves producing distinctive skeletonizing wounds(7)
Internet References
Species pages: anon.(5) | anon.(8)
Works Cited
1.Pests of fruit crops: a colour handbook
Alford D.V. 2007. Academic Press. 480 pp.
2.Nearctic sawflies. III. Heterarthrinae: Adults and larvae (Hymenoptera: Tenthredinidae)
D.R. Smith. 1971. Agricultural Research Service, USDA Technical Bulletin No. 1420. 84 pp.
3.Keys to the insects of the European part of the USSR. Vol. 3. Hymenoptera. Part 6.
Zhelokhovtsev A.N., Tobias V.I., Kozlov M.A. 1993. Keys to the Fauna of the USSR 158: 1-432.
4.Taeger A., Cincotta S., Susko E. (-2013) Kinds of Symphyta on Discover Life
5.University of Alberta Entomology Collection
6.Eastern Forest Insects
Whiteford L. Baker. 1972. U.S. Department of Agriculture · Forest Service.
7.Garden Insects of North America : The Ultimate Guide to Backyard Bugs (Princeton Field Guides)
Whitney Cranshaw. 2004. Princeton University Press.
8.NatureSpot: recording the wildlife of Leicestershire and Rutland