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Species Cybister fimbriolatus

large Dytiscus, ventral view - Cybister fimbriolatus Cybister fimbriolatus (Say) - Cybister fimbriolatus - male Diving Beetle - Cybister fimbriolatus - female Diving Beetle - Cybister fimbriolatus Cybister fimbriolatus? - Cybister fimbriolatus Cybister fimbriolatus - female Cybister fimbriolatus St. Andrews beetle unknown 2021 4 - Cybister fimbriolatus
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Adephaga (Ground and Water Beetles)
Family Dytiscidae (Predaceous Diving Beetles)
Tribe Cybistrinae
Genus Cybister
Species fimbriolatus (Cybister fimbriolatus)
Other Common Names
Giant Diving Beetle(1)
Synonyms and other taxonomic changes
Cybister dissimilis Aubé 1838, Cybister flavocinctus Aubé 1838, Cybister ellipticus LeConte 1852, Cybister cavicollis Sharp 1887, Cybister crotchi Wilke 1920(2)
Explanation of Names
Cybister fimbriolatus (Say 1823)
fimbriolatus = 'fringed' (refers to the metatarsal vestiture)
26-33 mm
Similar to Dytiscus, but metatarsal claws different. Elytra and pronotum smooth in male. Dilated male protarsus differs in details from that of Dytiscus(1)(3). Female Cybister has fine furrows on pronotum.(3)
se. Canada to FL west to ON-ND and across so. US to so. CA & throughout Mexico to the Yucatán; Bahamas(2)
Found in open, deeper water in permanent ponds, ditches, and other standing water(4)
Much of year in the south
both larva and adult prey on aquatic insects, fish, etc.
There are no longer any accepted subspecies of C. fimbriolatus(2)
See Also
Works Cited
1.Introduction to North American Beetles
Charles S. Papp. 1984. Entomography Pubns.
2.Review of the genus Cybister Curtis, 1827 (Coleoptera: Dytiscidae: Dytiscinae: Cybistrini) in North America
Miller K.B. 2013. Col. Bull. 67: 401-410.
3.Peterson Field Guides: Beetles
Richard E. White. 1983. Houghton Mifflin Company.
4.Beetles of Eastern North America
Arthur V. Evans. 2014. Princeton University Press.