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Family Byrrhidae - Pill Beetles

Pill Beetle - Cytilus alternatus Pill Beetle - Byrrhus Pill beetle from Jasper 10.07.11 - Simplocaria metallica beetle found under a rock or under a block of wood - Byrrhus Simplocaria metallica	 - Simplocaria metallica Cytilus.... - Cytilus alternatus Morychus oblongus 4 mm beetle - Cytilus mimicus
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 Elateriformia)
Superfamily Byrrhoidea (Pill, Water and Toe-winged Beetles)
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
Key to ne. NA spp. in(4)
most of Canada and n. half of the US; mostly boreal and montane, most NA taxa are restricted to the west(1)(5); 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.The Byrrhidae (Coleoptera) of Atlantic Canada
C.G. Majka, D. Langor. 2011. Journal of the Acadian Entomological Society. 7: 32-43.
5.Adventive and native Byrrhidae (Coleoptera) newly recorded from Prince Edward Island
Majka C.G., Noronha C., Smith M. 2006. Zootaxa 1168: 21-30.