Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Clickable Guide
Moths Butterflies Flies Caterpillars Flies Dragonflies Flies Mantids Cockroaches Bees and Wasps Walkingsticks Earwigs Ants Termites Hoppers and Kin Hoppers and Kin Beetles True Bugs Fleas Grasshoppers and Kin Ticks Spiders Scorpions Centipedes Millipedes


Family Psephenidae - Water Penny Beetles

Water Penny Beetle - Psephenus herricki Water Penny Beetle - Psephenus herricki - female Water Penny Beetle - Ectopria nervosa Water penny exuviae - Psephenus herricki Psephenus herricki Ectopria sp. - Ectopria Aquatic Critter - Ectopria Dicranopselaphus variegatus Horn - Dicranopselaphus variegatus
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 Byrrhoidea (Pill, Water and Toe-winged Beetles)
Family Psephenidae (Water Penny Beetles)
Explanation of Names
Psephenidae Lacordaire 1854
Water penny: larvae are flat, often circular
16 spp. in 6 genera in our area(1), ~300 spp. in 15 genera total(2)
3-7 mm(1)
Adults flattened, usually dark:

Larvae aquatic, distinctive, cling to rocks and found more often than adults:
worldwide, most diverse in E. Asia; Eubrianacinae (represented in our area by Eubrianax) are circumpacific, Psepheninae (represented in our area by Psephenus) are primarily a New World group, and Eubriinae (the rest of our genera) are globally distributed(1)
Larvae on the underside of rocks of submerged wood in fast-flowing water. Adults on rocks and vegetation along streams.
Adults only in summer(1)
Larvae graze on algae; some are detritivorous(1); adults are short-lived
Life Cycle
semivoltine; larvae overwinter, pupate under riparian substrates or in water(1)
Print References
Internet References
Family page (Hammond 2009)
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.Order Coleoptera Linnaeus, 1758. In: Zhang Z.-Q. (ed.) Animal biodiversity: An outline of higher-level classification...
Slipinski S.A., Leschen R.A.B., Lawrence J.F. 2011. Zootaxa 3148: 203–208.
3.Water Beetles of South Carolina
Janet Ciegler. 2003. Clemson University.
4.Lawrence J.F., et al. (2000-2005) Elateriformia (Coleoptera): descriptions, illustrations, identification...