

Click to embiggen
It’s not a flying fish, but something called a “sapphirine gurnard,” which is unusual not because it flies, but because it walks along the bottom using little finger-like fins that aren’t really visible in this painting but that look something like this.
This image came from the fifth, fishy volume of Gemeinnüzzige Naturgeschichte des Thierreichs, by Georg Heinrich Borowski, a late-18th-century naturalist, illustrated by D.F. Sotzmann.
The whole book is available on Biodiversity Heritage Library, but I found the picture on the Scientific Illustration tumblog.