Fauna
Insect

Tropisternus glaber

Tropisternus glaber

Also known as Smooth Water Scavenger Beetle

Smooth water scavenger beetles propel themselves through quiet freshwater using alternating strokes of their hair-fringed hind legs. Adults carry a silvery film of air trapped against dense hydrofuge hairs on their undersides, allowing them to remain submerged while grazing on algae and dead organic matter. During warm summer nights, these strong fliers readily disperse between ponds and frequently gather around artificial lights.

AquaticFreshwaterNocturnal
Tropisternus glaber reference
(c) Owen Strickland, some rights reserved (CC BY), uploaded by Owen Strickland · cc-by
—observations
—countries
—peak records
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Key facts
Diet & preyFilamentous algae, Aquatic detritus, Decomposing insects
Predators
  • Largemouth bass
  • American bullfrog
  • Mallard
ThreatsWetland degradation, artificial water drainage, and chemical pollution
HabitatsFreshwater ponds, marshes, ditches, and sluggish streams
Life span1–2 years
Classification
  1. OrderColeoptera
  2. FamilyHydrophilidae
  3. GenusTropisternus
  4. SpeciesTropisternus glaber
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Safe to observe at a normal distance.
Responsible observation
  • Nighttime lights: Check ground surfaces around outdoor lamps on warm summer nights for dispersed adults.
  • Pond dipping: Sweep a fine-mesh aquatic net through dense submerged weeds in standing water.
  • Observing air bubbles: Place a specimen in a clear jar of pond water to see the silvery air film beneath its abdomen.
Related species
Help improve the field guideSomething wrong?

Report a name, category, or profile issue for review.

Checking your Fauna account…