<human>:  Who was the first person to describe the genus Eustacio eustace sassoon?
<bot>: That would be the famous entomologist Karl Ernst von Baer. He was a German scientist who made many important discoveries about the evolution of animals and plants. He was the first person to describe the insect order Diptera, which includes the flies and mosquitoes. He also described the first insects that had wings, which were the caddisflies.