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Species Fenusa pumila - Birch Leaf-mining Sawfly

Birch Leafminer - Fenusa pumila - female Fenusa pumila Fenusa pumila Fenusa pumila - Birch Leafminer on Gray Birch - Fenusa pumila Fenusa pumila - Birch Leafminer on Gray Birch - Fenusa pumila Fenusa pumila - Birch Leafminer on Gray Birch - Fenusa pumila Blotch mine on river birch - Fenusa pumila Blotch mine on river birch - Fenusa pumila
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 Fenusini
Genus Fenusa
Species pumila (Birch Leaf-mining Sawfly)
Synonyms and other taxonomic changes
Fenusa pusilla auct. (the name prevailing in the American literature)
Explanation of Names
Fenusa pumila Leach 1817
avg. BL: ♂ 3.5 mm, ♀ 3.7 mm(1)
native to, and widespread across the Palaearctic, adventive in NA (NF-AB to MD-IA, AK-OR)(1)(2)
hosts: Betula spp.(1); prefers gray birch or gray birch hybrids, also attacks ornamental European white birch and its cut-leaf varieties(3)
Life Cycle
3-4 generation per year; overwinter as prepupae in soil(3)
Eearliest NA record: CT 1923(1)
17 parasitoid spp. are known to attack this species; the ichneumonids Lathrolestes nigricollis and Grypocentrus albipes, and the eulophid Chrysocharis nitetis have been introduced into North America from Europe to control it
An ichneumon wasp, Phanomeris phyllotomae, was imported into New England and New York in 1930s as a control agent. It is established but its effectiveness at control has yet to be determined.(4)
Internet References
Species pages: Ellis (2007) (Europe)(5) | Edmunds (2007) (UK)(6) | Pitkin et al. (2007-) (UK)(7)
Works Cited
1.Nearctic sawflies. III. Heterarthrinae: Adults and larvae (Hymenoptera: Tenthredinidae)
D.R. Smith. 1971. Agricultural Research Service, USDA Technical Bulletin No. 1420. 84 pp.
2.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.
3.Field guide to common insect pests of urban trees in the Northeast
Hanson T., Walker E. 2002. Waterbury, VT: Department of Forests, Parks and Recreation. 35 pp.
4.Eastern Forest Insects
Whiteford L. Baker. 1972. U.S. Department of Agriculture · Forest Service.
5.Ellis W.N. (2007-) Leafminers of Europe
6.British leafminers
7.Pitkin B., Ellis W., Plant C., Edmunds R. (2007-) The leaf and stem mines of British flies and other insects
8.Rutgers New Jersey Agricultural Experiment Station fact sheets & bulletins
9.University of Minnesota Extension
10.Ohio State University Extension fact sheets