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Species Nacerdes melanura - Wharf Borer

Beetle - Nacerdes melanura Beetle - Nacerdes melanura Wharf Borer - Nacerdes melanura Nacerdes melanura? - Nacerdes melanura Driftwood beetle - Nacerdes melanura Beetle/weevil - Nacerdes melanura Nacerdes? - Nacerdes melanura wharf borer larva - Nacerdes melanura
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Polyphaga (Water, Rove, Scarab, Long-horned, Leaf and Snout Beetles)
No Taxon (Series Cucujiformia)
Superfamily Tenebrionoidea (Fungus, Bark, Darkling and Blister Beetles)
Family Oedemeridae (False Blister Beetles)
Subfamily Oedemerinae
Tribe Nacerdini
Genus Nacerdes
Species melanura (Wharf Borer)
Synonyms and other taxonomic changes
Nacerdes melanura (Linnaeus)
Orig. Cantharis melanura Linnaeus 1758
Female. Length 9.8-13.5 mm. Male. Length 9.4-11.3 mm (1)
native to the Old World (probably continental Europe); now cosmopolitan and widespread in NA (esp. common in coastal states along the Atlantic and Pacific and around the Great Lakes; also in some inland sites)(1)(2)
First reported in Annapolis Royal, Nova Scotia, 1935
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)
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)
See Also
Common Red Soldier Beetle (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.PaDIL – High quality images and information tools designed for Biosecurity and Biodiversity