At https://phys.org/print454252017.html … a fossil horse foal has been uncovered in Yukatia in Russia – perfectly preserved in the permafrost. It still has its skin, hair and tail/ It is estimated to have died between 30 and 40,000 years ago.
Meanwhile, a much more ancient animals is the subject at https://phys.org/print455179220.html … dragonflies. A hundred million years ago giant insects lived contiguous with large reptiles and dragonflies – including giant dragonflies.
At the time equatorial forest covered central France. During the Carboniferous other insects were also large – including cockroaches and beetles, as a result it is thought of a higher percentage of oxygen in the air. How different were dragonflies back then and dragonflies in the modern world? Size seems to be the only difference. However, in the modern tropics one may come across very large butterflies and beetles. Even stick insects can range in size up to 50cm in length. Obviously, why giant dragonflies were extent long ago and not now is an unknown, and subject to theorising.
… the giant insects appear to have died out at the Permian/Triassic boundary (extinction event) and it is thought this occurred prior to the rise of flying reptiles and somewhat before the dinosaur dominance. It is unclear if this is theory or fact.