|MadSci Network: Zoology|
I completely concur with your observations. The pond striders that people normally notice are from the family Gerridae, which have an elongated thorax. During the winter, adult pond skaters stay on land (probably due to a combination of icy weather and a lack of food on the surface film) where they are far less noticeable. They also tend to avoid staying on the surface film when it rains because it becomes quite precarious for them.
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