Hydrometridae

Definition

A family of semiaquatic true bugs (Hemiptera) commonly known as marsh treaders or water measurers, characterized by an extremely elongated, slender head and body that allows them to stride across the water surface film while foraging for small arthropod prey.

Etymology

Example

Hydrometridae such as Hydrometra stagnorum are found along the margins of ponds and slow streams, where their stilt-like legs and elongated profile enable them to exploit the water surface tension zone unavailable to most other predators.

Synonyms

• Marsh treaders
• Water measurers

Related Terms

• Gerromorpha
• Hemiptera
• surface tension
• semiaquatic
• Hydrometroidea
• Water striders

Usage Notes

The common name 'water measurers' refers to the insects' superficial resemblance to a measuring stick when viewed against the water surface, not to any quantitative behavior. Hydrometridae are distinguished from the more familiar Gerridae (water striders) by their elongated head and more deliberate, walking gait rather than skating locomotion.