Water Striders (Aquarius remigis) | Insects That Walk on Water and Hunt Mosquito Larvae
Water Striders (Aquarius remigis)
The Graceful Gliders of the Water's Surface
If you’ve ever spotted a small insect skating effortlessly across the surface of a pond or canal, chances are you’ve encountered a Water Strider (Aquarius remigis). These fascinating aquatic insects possess the remarkable ability to "walk on water," thanks to their long, slender legs covered with microscopic hairs. As agile surface predators, they thrive in freshwater habitats—chasing down prey with speed and precision unmatched by most insects.
Basic Information
- Common Name: Water Striders
- Scientific Name: Aquarius remigis
- Family: Gerridae
- Order: Hemiptera
Morphology & Biology
Body Length: 2.0 – 12.0 mmColor: Dark brown to black
Wings: Both winged and wingless forms exist
Eyes: Prominent compound eyes
Antennae: Filiform (thread-like)
Wings:
- Forewings: Hemelytra (hardened base, thin tips)
- Hindwings: Membranous
Legs:
- Second and third pairs are elongated and slender
- Covered with microsetae (fine hairs)
- Traps air to create surface tension and prevent sinking
Unique Adaptations & Behavior
- Capable of walking or running on water using surface tension
- Inhabit calm freshwater surfaces such as ponds, ditches, and small lakes
- Uses ripples on the water to detect prey and mates
Life Cycle (Incomplete Metamorphosis)
Egg Stage- Incubation: ~7–10 days
- Development to adult: ~60–70 days
- Average lifespan: ~10–20 days
Total life cycle: ~2–3 weeks
Diet & Hunting Behavior
Main Diet:
- Mosquito larvae
- Small aquatic insects
- Micro-crustaceans
Predatory Behavior:
- Uses front legs to snatch prey
- Pierces with piercing-sucking mouthparts
- Feeds by extracting body fluids from its prey
Global Distribution
Water Striders are found worldwide, particularly abundant in tropical and subtropical regions, including:
- The Americas
- Africa
- South Asia
- Southeast Asia, including Thailand
Ecological Role
- Controls mosquito populations and small aquatic insect pests
- Serves as an indicator of water quality
- Not harmful to crops or plants
- Plays a vital role in maintaining surface water ecosystem balance
Did You Know?
Harmless to humans:- They don’t bite or sting
- Not poisonous
- Ideal for studying buoyancy, surface tension, and insect biomechanics
✅ Conclusion
The Water Strider (Aquarius remigis) may appear small and ordinary, but it is a remarkable example of evolutionary adaptation. With its unique locomotion, efficient predation, and ecological value, this insect plays a crucial role in freshwater ecosystems—especially in controlling mosquito populations. Whether studied for its physical adaptations or ecological importance, the Water Strider stands out as one of nature’s most graceful and efficient surface dwellers.
Water Striders (Aquarius remigis) — 3 High-Intent FAQs
Q: 1 How do water striders “walk on water”—what’s the actual physics?
A: Tiny, waxy hairs (microsetae) on their middle and hind legs make the legs super-hydrophobic, so water can’t wet them. That, plus long legs that spread weight out, lets them ride surface tension like a trampoline. They push against the surface with a quick rowing stroke, creating vortices that propel them forward without breaking the water film.Q: 2 Do water striders bite people or hurt fish? Are they good or bad for ponds?
A: They don’t bite or sting humans and don’t carry human diseases. They’re helpful surface predators that eat mosquito larvae, midges, and small insects. In very shallow nursery setups they may nab tiny fish fry at the surface, but in most garden ponds they’re a net benefit for insect control.3) How can I encourage (or reduce) water striders in a backyard pond?
A:- Encourage (for mosquito control): keep some calm, still water, add a little floating vegetation, avoid broad-spectrum insecticides, and limit bright night lighting that disrupts hunting.
- Reduce (to protect fry): add gentle aeration/surface ripples, skim surface films, house fry under fine mesh covers, and stock a few small, noninvasive fish that don’t eat fry but will deter striders (or relocate striders with a dip net).
