Thursday, August 31, 2017

Peewee Leggy Bugs--Water Striders

Jesus! A bug type that can walk on water!

A neighbor walking with us spotted a bug he considered a "leggy bug", like several I had written about the last few months. From looking at images and diagrams of proportionally for legs vs. body length, I could agree. However, after peering more into the water strider (aka pond skater), I'd characterize the bug as a peewee leggy bug. These striders' body lengths measure only about 1/2". Their legginess, however, helps them navigate on water surfaces.

From Osborn School site "Water Strider"—"½ of an inch long … sometimes called 'Pond Skater', can run across the surface of the water, very sensitive to movement".

Enchanted Learning's site "Water Strider" has similar information with a descriptive diagram.
The water strider (also known as the pond skater) is a true bug that can run across the surface of water … The underside of the body is covered with water-repellent hair. … Most water striders are over 0.2 inch (5 mm) long. … The long, middle legs move this bug across the surface on the water like paddles. The long hind legs steer them and act as brakes. The short front legs are used to catch prey.
Coincidentally, I wrote about a "true bug" previously—the leaf-footed bug that visited me at one of my porch columns "Leaf-footed Bug Visitor". The commonality—piercing mouth parts: In the case of the water strider in BugFact's "Water Strider (True Bug)" site, using the bug POV, "[I] use my piercing mouth parts to suck the juices primarily from other insects or spiders, alive or dead."

Is the water strider a leggy bug like several I have written about recently? Yep, if considering ratios of body parts. "Water Strider (True Bug)" emphasis on legs—"I am able to slide along the surface of the water by distributing my weight evenly on my long legs. … I have two antenna and six long thin legs. My front legs are shorter than my back legs."

Bugguide.net's "Family Gerridae - Water Striders", shows the size to be a puny (3-16 mm, about .12 to .63 inches)—not as impressive as walking sticks, crane flies, or huntsman spiders.

An informative site, seemingly hostile to water striders, is PestWiki's "Water Strider: 8 General Facts and How to Get Rid of Them". (The descriptive illustration is pretty cool.)
They have short front legs which help them to capture aquatic insects in ponds. They also have wings on dorsal sides. They use their middle pair of hydrophilic legs for propulsion and their hind pairs for steering. The adult water striders come in two species i.e. one with wings n (sic) the other without wings.
How It Works' "How do water striders walk on water?" provides another description of mechanics and water-coping ability of this bug:
Despite being denser than water, a water strider doesn’t doesn’t sink; … The forces of attraction between all the molecules in the water pull the molecules at the surface together so that they lock like a thin elastic membrane of slightly denser molecules.…

The middle pair of legs, lying ?at on the water, are used as oars to ‘row’ over the surface while the rear pair act like rudders for steering. Long, splayed legs enable the pond skater to distribute its weight evenly over a greater surface area, further helping it to float.
Some TouTube Videos About Water Striders with Emphasis on Water-walking Talents
A Male Water Strider Species with Captivating Courtship

"Male water striders evolved antennae to grab females by the eyes" describes a study of rheumatobates rileyi species of water strider. The male bug mates with the female, first using his antennae to physically capture her eyes. Besides vivid descriptions, the article includes a video of the couple in action.

2 comments:

Woody Lemcke said...

Very interesting! Just love your opening lines too!

whilldtkwriter said...

Thx for compliments!