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Family Byrrhidae - Pill Beetles

Pill Beetle - Byrrhus Pill Beetle - Byrrhus Cytilus alternatus Byrrhidae: Byrrhus? - Byrrhus another byrrhid? - Amphicyrta Beetle - Byrrhus Pill Beetle - Byrrhus Byrrhidae - Morychus oblongus
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Polyphaga
No Taxon (Series Elateriformia)
Superfamily Byrrhoidea
Family Byrrhidae (Pill Beetles)
Other Common Names
Moss Beetles
Explanation of Names
Byrrhidae Latreille 1804
common name: when disturbed, beetle retracts appendages into ventral recesses, forming a compact "pill"
35 spp. in 15 genera north of Mexico(1)(2), 430 spp. in ~40 genera worldwide(3)
Overview of our faunaFamily BYRRHIDAE
Subfamily Byrrhinae
Keys to spp.: NA(4) · ne. NA(5)
most of Canada and n. half of the US; mostly boreal and montane, most NA taxa are restricted to the west(1)(6); also Eurasia and the tropics
sandy shorelines, beneath logs and stones, among grass roots, and mossy habitats in general
adults fly during spring and early summer
most feed on moss; occasionally on liverworts, lichens, and grass roots
Most adults are active at night or in dim light; Morychus and Cytilus may be active in open areas on sunny days
See Also
members of other families may look similar
Works Cited
1.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.
2.Johnson P.J. (-2013) Project Byrrhus
3.Order Coleoptera Linnaeus, 1758. In: Zhang Z.-Q. (ed.) Animal biodiversity: An outline of higher-level classification...
Ślipiński S.A., Leschen R.A.B., Lawrence J.F. 2011. Zootaxa 3148: 203–208.
4.Taxonomic notes, new records, and a key to the adults of North American Byrrhidae (Coleoptera)
P. J. Johnson. 1991. Proceedings of the Entomological Society of Washington, Vol. 93, pp.322-332.
5.The Byrrhidae (Coleoptera) of Atlantic Canada
C.G. Majka, D. Langor. 2011. Journal of the Acadian Entomological Society. 7: 32-43.
6.Adventive and native Byrrhidae (Coleoptera) newly recorded from Prince Edward Island
Majka C.G., Noronha C., Smith M. 2006. Zootaxa 1168: 21-30.