Aquatic Macroinvertebrate Identification

Kingdom   Phylum  Class  Order  Family  Genus  Species

Ephemeroptera
(Mayflies)  
Diptera
(True Flies)
Megaloptera 
(Alderflies/Dobsonflies)
Plecoptera
(Stoneflies) 
Coleoptera 
(Beetles)
Hemiptera
(True Bugs)
Trichoptera
(Caddisflies)
Odonata
(Dragonflies/Damselflies)
Ephemeroptera

Key Characteristics:

  • Gills on abdomen

  • 2 or 3 cerci (tails)

  • 1 tarsal claw on each leg

  • Wingpads on thorax

  • No visible segments on thorax

 
 
Plecoptera

Key Characteristics:

  • Gills on thorax or not present

  • 2 cerci (tails)

  • 2 tarsal claws on each leg

  • Long antennae

  • Segmented thorax

 
Trichoptera

Key Characteristics:

  • Hook, brush, or prolegs at end of abdomen

  • Gills often on ventral or lateral abdomen

  • No wingpads

  • Antennae short or not visible

  • Sclerotized head

  • Soft, caterpillar-like abdomen

  • Can be free living or cased

 
Diptera

Key Characteristics:

  • Soft, fleshy body

  • Cylindrical in shape

  • No segmented legs, may have prolegs

  • Head small or not visible

  • Generally the flashy end is the posterior end

 
Coleoptera

Key Characteristics:

  • Sclerotized body

  • Both adults and larvae may be aquatic

  • Jointed legs

  • No wingpads on larva

  • Wings of adults modified into hardened, protective structure (elytra)

 
Odonata

Key Characteristics:

  • Long body with large head

  • Damselflies have gills on the posterior end of abdomen

  • Large, extendable lower jaw

  • Wingpads on thorax

  • Large eyes

  • 2 tarsal claws

 
Megaloptera

Key Characteristics:

  • Large gills along side of body

  • Large pincer mandibles

  • Long filament or hooks at end of abdomen

  • Eyes are a star shape

  • Sclerotized head

  • No wingpads

 
Hemiptera

Key Characteristics:

  • Suction mouthparts (haustellate) like a straw or a beak

  • Long, segmented legs - sometimes modified for swimming

  • Hardened or leathery front wings

  • N gills present

 

(406) 541-9287

802 E. Front St.
Missoula, MT 59802

©2020 by Watershed Education Network. Proudly created with Wix.com