THE XERCES SOCIETY FOR INVERTEBRATE CONSERVATION

Aquatic Invertebrates in Pacific Northwest Freshwater Wetlands
An Identification Guide and Educational Resource
fdsf
  Identify taxaJointed legsSix legsColeopteraAdult beetles

  Gyrinidae
(whirligig beetles)
Each eye is divided into two separate top and bottom sections that may touch or form two completely separate eyes. Short, clubbed antennae; middle and hind legs are flattened and oar-like. 		  gyrinidaegyrinidaegyrinidae
       
  Elmidae
(riffle beetles)
Small robust body (<10mm); long threadlike antennae. Legs are not oar-shaped and lack hairs. 		  elmidaeelmidaeelmidaeelmidae
       
  Dryopidae
(long-toed water beetles)
Similar to elmids, but antennae are short and thick, with short, expanded, comb-like terminal segments. 		  dryopidaedryopidaedryopidaedryopidae
       
  Haliplidae
(crawling water beetles)
A pair of large ventral plates cover the bases of the hind legs and most segments of the abdomen. Hind legs may have swimming hairs. Robust convex body, >2mm, often patterned or spotted. 		  haliplidaehaliplidaehaliplidaeHaliplidae
       
 

Curculionidae
(water weevils)
Mouthparts elongated into very distinctive long, blunt snout extending from the front of the head; small, robust and convex body.

 
       
  Noteridae
(burrowing water beetles)
Streamlined, robust, convex oval bodies without a visible scutellum. Tibia of the front leg forms a long hook that projects laterally from the remaining leg segments. Antennae are long and threadlike, with all segments of equal length. Easily confused with Dytiscidae. 		 
       
  Dytiscidae
(predaceous diving beetles)
Very diverse family, generally with streamlined, robust, convex oval bodies and long threadlike antennae. Most easily confused with Noteridae, but front legs lack a tibial spur, and the scutellum is often visible. 		  DytiscidaeDytiscidaeDytiscidaeDytiscidae
       
 

Hydrophilidae
(water scavenger beetles)
Very diverse in size, shape, color and pattern. Bodies are robust, oval to elongated, and generally convex. Labial palps may be long and easily mistaken for antennae. The antennae are shorter and may be hidden beneath the head; terminal 3 segments are expanded into a small club which may have a cup-like appearance.

  hydrophilidaehydrophilidaehydrophilidae
       
  Sphaeriusidae (Microsporidae)
(minute bog beetles)
Tiny oval body <1mm long. Body is convex and glossy; antennae have small clubs at tip. Thin plates from the underside of the thorax cover much of the underside of the first couple abdominal segments (similar to Haliplidae).		  
     
 

Coleopterans uncommon in wetlands

Helophoridae (helophorid beetles)
Hydraenidae (minute moss beetles)
Hydrochidae (hydrochid beetles)
Psephenidae (water pennies)

  hydraenidaehydraenidaehydraenidae
 
fdsf

© 2007 Xerces Society
Contact info@xerces.org