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Species Gibbium aequinoctiale - Smooth Spider Beetle

Unidentified Insect - Gibbium aequinoctiale Spider beetle - Gibbium aequinoctiale Spider Beetle - Gibbium - Gibbium aequinoctiale Spider Beetle - Gibbium - Gibbium aequinoctiale Beetle - Gibbium aequinoctiale Longitarsus sp.? - Gibbium aequinoctiale Longitarsus sp.? - Gibbium aequinoctiale Gibbium aequinoctiale ? - Gibbium aequinoctiale
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)
Superfamily Bostrichoidea (Carpet, Powder-post and Death-watch Beetles)
Family Ptinidae (Death-watch and Spider Beetles)
Subfamily Ptininae (Spider Beetles)
Tribe Gibbiini
Genus Gibbium
Species aequinoctiale (Smooth Spider Beetle)
Synonyms and other taxonomic changes
references to Gibbium psylloides outside the Old World are most likely this species
Explanation of Names
Gibbium aequinoctiale Boieldieu 1854
2.1–2.7 mm(1)
Elytra fused and inflated, completely glabrous (smooth). Can only be confused with Mezium, but pronotum distinctive.
often confused with G. psylloides(1)
Cosmopolitan but more common in warm climes(2), and very few records in Europe; origin unknown ("tropical, subtropical"); found in stored goods across NA(3)(1)
prefer dark areas, mainly in houses, flour mills, occasionally warehouses, hospitals, stores(2)
wide variety of dead organic materials; may be a dry stored product pest stored seeds, wheat, bran, stale bread, decaying animal and vegetable refuse, rat droppings, stored wheat, baby food, dog biscuits, cereals, woolens, towels, leather, paste, and tallow and opium cake
has a remarkable ability to avoid drying out and can withstand temperatures as high as 56°C (133°F) (Yoder et al. 2009)
See Also
Mezium affine Boieldieu
Print References
Yoder JA, Chambers MJ, Tank JL, Keeney GD. 2009. High temperature effects on water loss and survival examining the hardiness of female adults of the spider beetles Mesium affine and Gibbium aequinoctiale. 8 pp. Journal of Insect Science 9: 68.
Internet References
Works Cited
1.Death-watch and spider beetles of Wisconsin—Coleoptera: Ptinidae
Arango, R.A. and D.K. Young. 2012. General Technical Report FPL-GTR-209. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory.
2.Beetles associated with stored products in Canada: An identification guide
Bousquet Y. 1990. Research Branch Agriculture Canada, Publication 1837.
3.Coleoptera families other than Cerambycidae, Curculionidae sensu lato, Chrysomelidae sensu lato and Coccinelidae -- Chapter 8.5
Denux O., Zagatti P. 2010. BioRisk 4: 315–406.