order
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Coleoptera
“Adult Beetles”
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Coleoptera
“Larval Beetles”
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Diptera
“True Flies”
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Ephemeroptera
“Mayflies”
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Hemiptera
“True Bugs”
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Lepidoptera
“Aquatic Caterpillars, Snout Moths”
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Megaloptera
“Alderflies, Dobsonflies, and Fishflies”
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Odonata
“Dragonflies and Damselflies”
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Plecoptera
“Stoneflies”
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Trichoptera
“Caddisflies”
family
Elmidae
“Riffle Beetles”
Genus Overview
There are 33 species in North America. Adults are small around 2-4 mm in length. Adults lack tomentum on the foretibia.
Characteristics
POLLUTION TOLERANCE
Southeast: 5.4 and higher
Upper Midwest: 5 and higher
Midwest: 3 and higher
Mid-Atlantic: 5 and higher
0 = least tolerant, 10 = most tolerant
FEEDING HABITS
Collector / Gatherer
Scraper / Grazer
Scraper / Grazer
MOVEMENT
Clinger
DISTRIBUTION
Widespread (east of the Rocky Mtns.)
HABITAT
Lotic-erosional
Diagnostic Characters
order
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Elytra
family
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5-Segmented Tarsi
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Big Claws
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Last Tarsal Segment
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Thread-like Antennae
genus
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Prosternal Process
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Tomentum of tibia
+ Expanded Character List
Order:
Adults with hardened forewings (elytra) covering the hind wings.
Family:
Terminal segment of each antenna no longer than combined length of 2 preceding segments; antennae thread-like. Elytra concealing entire abdomen or exposing only part of 1 tergite. Each leg with 5 tarsal segments, last tarsal segment about as long as other segments combined and with big claws. Abdomen with 5 visible segments.
Genus:
Prosternum process narrower than head. Antennae filiform and 11 segmented. Elytra without an accessory stria. Tibia without tomentum. Hind coxae transverse and larger compared to fore- and mid- coxae.
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Dorsal
Ventral