Another old fossil!

This is another fossil found at the nature reserve, this time a Micraster-type echinoid or sea urchin. It was found inside a split piece of flint when we were excavating butterfly scrapes in our restored chalk grassland. I'm not sure which Micraster species it is, but it would have alive in a shallow tropical sea between 60 and 90 million years ago. It's certainly far from tropical today!