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Tetropters

The animal on the foreground is a tetropter. There is not much detail to be seen, but the impression is that of an animal moving a bit like a helicopter, and that is indeed what tetropters look like. They have four wings, just like the tetrapterate flyer coming up to the tetropter, but there the similarity end. Tetrapterates are similar to birds, but with four wings of course, and their wings are built of bone, muscles and subcutaneous bubbles. In contrast, tetropters are much smaller, insect-like, and their wings are membranes. The most important difference is in the mode of flight: tetropters are radially-=built animals and have four wings that each beat clockwise and counterclockwise.
Tetropters have been discussed various time in the blog: I would start here, then read this one, followed by this post, to end here.

tetropter
tetranimation

The scheme shows how tetropter wings move. They each move to and fro over a quarter of a circle, and near the end of the circle they rotate along their long axis. The wing next to it does the same thng but in mirrored fashion, so the two wings move up close together and then are pulled apart. This is the so=called 'clap and fling' mechanism of generating lift that is used on Earth as well. Earth fluers only have two wings, so there is only one 'clap' for each movement cycle, but tetropters with their four wings have a 'clap' twice in each wing cycle.

Here is a more developed animation, showing a nondescript sphere, but moving about as a tetropter might. Tetropters are excellent at hovering flight and they are extremely manoeuvrable.

more animation