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Species Nacerdes melanura - Wharf Borer

Beetle - Nacerdes melanura Coleoptera - Nacerdes melanura Nacerdes melanura? - Nacerdes melanura Nacerdes? - Nacerdes melanura Nacerdes? - Nacerdes melanura Nacerdes melanura - Wharf Borer? - Nacerdes melanura Brown spruce longhorn beetle (Tetropium fuscum). - Nacerdes melanura Rhagonycha sp. - Nacerdes melanura
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Polyphaga
No Taxon (Series Cucujiformia)
Superfamily Tenebrionoidea
Family Oedemeridae (False Blister Beetles)
Subfamily Oedemerinae
Tribe Nacerdini
Genus Nacerdes
Species melanura (Wharf Borer)
Explanation of Names
Nacerdes melanura (Linnaeus 1758)
9.4-13.5 mm(1)
adventive in NA, mostly New England to Great Lakes and along west coast; also in some inland sites - Map (1)(2)(3), native to the Old World (mostly Europe)
Moist wood, where the larvae build long galleries; wharf timbers between flooding and the high water level especially which were in badly decayed, well-riddled wood
adults emerge about the same time every year; active Apr-Aug outdoors (year-round indoors)(1)
wet and decayed wood (softwoods & hardwoods); adults feed on pollen(1)
Larvae feed almost entirely on very moist wood and can be destructive of pilings under wharves and buildings near water.(4)
Life Cycle
usually one year (up to several years in cooler climates); mating and ovipositing occur in moist rotten wood, larvae develop in irregular galleries and pupate in small chambers; adults emerge in large numbers and live ~7 days(1)
They fly to light, often to windows; thousands may suddenly appear in/around a building, disrupt business operations and be a nuisance. Larvae may infest pilings under wharves and under buildings near the water, boardwalks along the sea coast, wood floors in damp basements, boats, greenhouse benches.(1)
Overwinter as adults inside buildings.(4)
See Also
Rhagonycha fulva has reddish-orange femora, dark antennae, and a different-shaped pronotum:
Internet References
Works Cited
1.Handbook of urban insects and arachnids: A handbook of urban entomology
Robinson W.H. 2005. Cambridge University Press.
2.American Beetles, Volume II: Polyphaga: Scarabaeoidea through Curculionoidea
Arnett, R.H., Jr., M. C. Thomas, P. E. Skelley and J. H. Frank. (eds.). 2002. CRC Press LLC, Boca Raton, FL.
3.Global Biodiversity Information Facility (GBIF)
4.Eastern Forest Insects
Whiteford L. Baker. 1972. U.S. Department of Agriculture · Forest Service.
5.PaDIL – High quality images and information tools designed for Biosecurity and Biodiversity