- 16 species known in North America
| Phylum: | Arthropoda |
| Class: | Insecta |
| Order: | Coleoptera |
| Family: | Psephenidae |
Identification Tips:
Larva
Highly flattened body; round or oval in shape
• Plates cover extend beyond body from most or all body segments
• Plates may overlap or have spaces between them
• 3 pair segmented legs and filamentous gills visible on under side
• 3-10 mm
Adults
• Near circular beetle just above water level on rock or wood with splashing water
• Usually in congregations
Life History:
• Larvae cling to rocks in riffles (fast flowing areas)
• Daylight hours usually spent underneath rocks; emerge at night to feed
• Graze on algae on rocks
• Mature larvae crawl out of water to sheltered locations to pupate
• Adults are short lived and seldom seen.
• Found at breeding sites; just above water level in fast flowing rocky areas of streams, often on rocks protruding from swiftly flowing, splashing water
| POLLUTION TOLERANCE | ||||
| Very Sensitive | Somewhat Sensitive | Facultative | Somewhat Tolerant | Very Tolerant |
| Most | ||||
| Pollution Indicator | Somewhat tolerant of metal pollution |
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Primary Information Source:
Voshell, J. Reese. 2002. A Guide to Common Freshwater Invertebrates of North America. McDonald and Woodward Publishing Company. Blacksburg, Virginia.
