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Species Saperda tridentata - Elm Borer

Elm Borer - Saperda tridentata Elm Borer - Saperda tridentata Elm Borer - Saperda tridentata Beetle ID - Saperda tridentata Elm Borer - Saperda tridentata Elm Borer? - Saperda tridentata Saperda tridentata - male Elm Borer - Saperda tridentata
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 Chrysomeloidea (Longhorn and Leaf Beetles)
Family Cerambycidae (Longhorn Beetles)
Subfamily Lamiinae (Flat-faced Longhorn Beetles)
Tribe Saperdini
Genus Saperda
Species tridentata (Elm Borer)
Explanation of Names
Saperda tridentata Olivier 1795
8-17 mm (1)

Elytra covered with powdery/pearly-gray to medium gray pubescence; orangish or reddish stripe along lateral margin, and 3 bands of same color across each elytron; basal band extends inward at right-angles to margin for short distance, then curves toward rear; middle band oblique, straight, extending from lateral margin to medial margin; two black spots on side of pronotum, and two more black spots on each elytron - one anterior to the basal band, and another posterior to the apical band
Deciduous woods containing elms
Adults from May to August
Larvae feed in galleries under bark of several species of elm - Ulmus spp.
Life Cycle
overwinters in pupal cells in sapwood of elm trees; adults emerge in May and June, and lay a single egg at night in crack of bark of stressed trees; larvae bore beneath bark in galleries; usually one generation per year
S. tridentata is not the main vector of Dutch Elm Disease but has been known to transmit the fungus (Ophiostoma ulmi) which causes the disease.
See Also
probably more common than S. lateralis, and much more common than S. imitans
S. lateralis has dark gray or blackish elytra with reddish-orange stripe along lateral and medial margins, no black spots, and (usually) no colored bands; elytral surface deeply punctate
S. imitans has dark gray elytra with 3 oblique orangish bands extending toward - but not touching - medial margin; middle band "free-floating" (its distal end is blunt and doesn't touch lateral stripe, and its proximal end is pointed and doesn't touch medial margin); no black spots on elytra
Print References
Dillon (2)
Yanega (1)
Internet References
Forestry Images - photos by James Solomon of adult emergence hole in bark, and live larvae in galleries beneath bark (
distribution in Canada; PDF doc - lists provinces Manitoba to Quebec (Cerambycidae: in Checklist of Beetles of Canada and Alaska)
Saperda species in NCSU collection; list - 67 pinned specimens of S. tridentata, including specimens collected in NC (North Carolina State U.)
Works Cited
1.Field Guide to Northeastern Longhorned Beetles (Coleoptera: Cerambycidae)
Douglas Yanega. 1996. Illinois Natural History Survey.
2.A Manual of Common Beetles of Eastern North America
Dillon, Elizabeth S., and Dillon, Lawrence. 1961. Row, Peterson, and Company.