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Species Cytilus alternatus

Coleoptera 5-17-10 01a - Cytilus alternatus Beetle - Cytilus alternatus Byrrhidae, lateral - Cytilus alternatus Cytilus alternatus Small Black Beetle  - Cytilus alternatus Don't know what to suggest for this one!? - Cytilus alternatus Cytilus alternatus? - Cytilus alternatus Pill Beetle - Cytilus alternatus
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)
Subfamily Byrrhinae
Tribe Byrrhini
Genus Cytilus
Species alternatus (Cytilus alternatus)
the only eastern species of the genus(1)
5-6 mm
body convex and oval (shaped like a football in lateral view), dark brown with metallic sheen visible in good light; anterior margin of pronotum ovate/rounded, posterior margin composed of two concave arcs meeting at the midline to form a sharp point; elytra mottled with light gray patches
across NA south to NJ-IN-UT-CA(2)
sandy beaches, under logs, leaves, stones, damp mossy habitats in general
adults fly in spring and early summer
adults and larvae feed on moss
Usually nocturnal but may sometimes be found in open areas on sunny days.
Internet References
drawing of larva (Zoological Institute of Russian Academy of Sciences)
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