Rare 4-petal mutation of the sand dollar Scutellaster oregonensis (Clark, in Dall, 1909) recently donated to our paleontological research by beachcomber and collector Wendy Frye and identified by Richard Mooi of the @California Academy of Sciences in San Francisco. This is from the Purisima Formation here in Santa Cruz and is on the order of 2-3 million years old. As you may recall, echinoids typically have pentagonal (5-part) symmetry, making this discovery on par with a 4-leaf clover. This one is on its way to the paleontology collections of the Academy tomorrow on my monthly migration. Thank you Wendy!

Some fossils are rarer than others...

 

Here is one of the more uncommon fossils from the Sandhills Habitat in Santa Cruz; the fossilized upper and lower claw of a crab from the Santa Margarita Formation rock layer. This is 10-12 million years old and I've only seen one of these in over 4 decades. The reason something like this isn't that common is because the Santa Margarita rock layer generally represents ancient higher energy environments consisting of areas of the ocean where course sands and gravels are deposited.