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
Heptageniidae
Stenacron
“Flat-headed Mayflies”
Genus Overview
7 species in North America. This genus is found in small streams to larger rivers. Identification to species is difficult and revision is probably needed.
Characteristics
POLLUTION TOLERANCE
Southeast: 1.7 - 7.1
Upper Midwest: 7 and higher
Midwest: 3.1 and higher
Mid-Atlantic: 4 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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Abdominal Gills
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Single Tarsal Claw
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Usually 3 Tails
Family
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Flat Head And Body
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Margin Around Eyes
+ Expanded Character List
Order:
Wings developing in wing pads. Mouthparts suitable for chewing. Gills present on tops and sides of abdomen. Segmented legs present. One tarsal claw per leg. Usually with 3 tails (sometimes 2).
Family:
Head and body dorsoventrally flattened (depressed). Eyes and antennae positioned dorsally. Lateral margins of head visible beside the eyes. Mandibles not visible from dorsal side. Claws much shorter than tarsi. Tibiae and tarsi straight. Abdominal gills on segments 2–7 variably shaped depending on genus and species.
Genus:
Gills are pointed, last gill is different in structure to preceding ones
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Dorsal
Ventral