Some fossilized friends from the Pliocene Purisima Formation of Santa Cruz

 

The extinct sand dollar species Dendraster ashleyi / D. gibbsii and the crab Cancer sp.

“Cliona, the Parasitic Marine Sponge”

 

Some sea sponges like this 5 million year old Cliona here are parasitic, drilling into the calcium carbonate shells of other marine creatures to set up residence, in this case the host shell of a giant princess slipper snail, Grandicrepidula princeps. What we are seeing here is the fossilized trace of the Cliona sponge’s drillings on the inside of the snail's shell; a calcitic cast of the  internal mesh chambers of the sponge's drillings inside the snail's shell.  Like an ant mound casting, this represents the trace of the sponge’s home, a cast of it, inside the shell of the snail, a subfield of paleontology dealing with traces of ancient life called “ichnology”.  The drilling traces of the sponge can be so advanced and weakening the shell that the snail would have been more vulnerable to predators, making the interaction truly parasitic.You Tube Video: ​​https://youtu.be/bLPpwTlfiog

 

Advancements in Best Practices for Mitigation Paleontology
First update in the last 15 years to guide mitigation paleontology in California and elsewhere. This is super important for our practice and gives teeth to the foundational work of Paul Murphey, et. al. 2019, "A Foundation for Best Practices in Mitigation Paleontology". What is still needed is legislative protections and guidelines akin to what archeology has in place. Much more work is needed. https://www.paleosolutions.com/wp-content/uploads/2019/05/Murphey-et-al.-2019-Best-practices-in-mitigation-paleontology.pdf, and https://vertpaleo.org/wp-content/uploads/2025/10/SVP_Mitigation_Paleontology_Best_Practices_First_edition_October_2025.pdf

The Giant Carnivorous Sea Snail Clinopegma stantoni

The story of Clinopegma stantoni has been simmering here in Santa Cruz County for the past 116 years but is one that has been 5 million years in the making!  A little background on the name and history of this giant sea snail: Clino refers to slope and pegma is peg = pointed stick  The species is named in honor of Dr. Timothy W. Stanton, chief paleontologist. United States Geological Survey, whose work on Mesozoic faunas is well known.

The genus Clinopegma was named by Ulysses S. Grant, IV and Hoyt Rodney Gale published in 1931 in their monumental work on Pliocene and Pleistocene fossil mollusks of California.  Interestingly, here, U.S. Grant the IV, was the grandson of Ulysses S. Grant the first, president of the United States.  His grandson became a distinguished professor of paleontology at Berkeley

With regards to Clinopegma stantoni the species was named by Ralph Arnold in 1908 from the Año Nuevo park on the south side of the point in the upper member of the Purisima Fm. between Tunitas Creek and Pescadero Creek and near Ano Nuevo Creek in San Mateo County and also between New Brighton and Capitola beaches here in Santa Cruz and a couple other minor places and that’s it!

Coincidentally, Arnold also named a brand new species of Brittle Star, Amphiura sanctaecrucis that very same year of 1908 and that was discovered high up in the Santa Cruz Mountains and recently re-discovered en masse, dozens of individuals, in what’s called a brittle bed, but more on that in the movie…

Interested in Paleontology and Fossils?

 

If you are in Santa Cruz tonight and looking for some fun fossiliferous festivities, please consider dropping by the Santa Cruz  Museum of Natural History and checking out our booth Pacific Paleontology, Inc. and looking into our new Internship Programs for kids and adults!  https://bit.ly/PaPaExpedition   https://loom.ly/BLtV_VE .

Air scribe technique for one of our recent fossil whale discoveries...

 

Air scribe technique for one of our recent fossil whale discoveries...

Paleontological Find of the Century!

 

This is quite possibly the paleontological find of the century in Santa Cruz, literally!  An extinct deep sea brittle star, named over 120 years ago in honor of Santa Cruz; Amphiura sanctaecrucis, found high up in the Santa Cruz Mountains!  With gratitude out today to forthcoming coauthors Charles L Powell, John Barron, Sabine Stöhr, and others.

https://hilltromper.com/article/rare-santa-cruz-brittle-star-fossils-shine-new-light-local-paleontology