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Species Nematus ventralis - Willow Sawfly

Spotted caterpillar - Nematus ventralis Unknown caterpillars  (DCP86) - Nematus ventralis caterpillar - Nematus ventralis Willow Sawfly Larvae - Nematus ventralis Willow larvae - Nematus ventralis Willow Sawflies - Nematus ventralis Willow Sawflies - Nematus ventralis what moth or butterfly - Nematus ventralis
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 Nematinae
Tribe Nematini
Genus Nematus (Willow Sawflies)
Species ventralis (Willow Sawfly)
Explanation of Names
Nematus ventralis Say 1824
Nematus suratus Fitch, 1856. N. Y. Agr. Soc, Trans. 3: 315.
Pteronus latus Marlatt, 1896. U. S. Dept. Agr., Div. Ent. Tech. Ser. 3: 48.
Nematus latus Cresson, 1880.
Hypolaepus viereckii Bradley, 1903. Canad. Ent. 35: 47.
Pteronidea edita MacGillivray, 1920. Canad. Ent. 52: 235.
Krombein, et al. 1975 in vol 1 places Nematus ventralis in the ventralis species group which includes an additional 7 species of which at least 4 are known to feed on Salix. (1)
Adult - see original description by Say 1824 in print references below.
All stages - see Howard 1888 in print references below. Includes illustration of adult.
PQ-NC west to AB-MT-CO (map)
Willow but also reported on cheery. See Packard 1890 in print references below.
Life Cycle
may produce multiple generations; larvae may be dormant for two winters(2)
may be abundant on willow in c. US & Prarie Provinces(2)
Print References
Howard, L.O. 1888. The Yellow-spotted Willow-slug. (Nematiis ventralis Say.) [Order Hymenoptera: Family Tenthredinidae.] Insect Life 1(2): 33
Say, T. 1824. In Keating, Narr. Long's 2nd Exped. 2(App 1): 315
Packard, A.S. 1890. Fifth report of the United States Entomological Commission, being a revised and enlarged edition of Bulletin no. 7, on insects injurious to forest and shade trees. p. 524
Works Cited
1.Catalog of Hymenoptera in America North of Mexico
Karl V. Krombein, Paul D. Hurd, Jr., David R. Smith, and B. D. Burks. 1979. Smithsonian Institution Press.
2.Garden Insects of North America : The Ultimate Guide to Backyard Bugs (Princeton Field Guides)
Whitney Cranshaw. 2004. Princeton University Press.