#fossilized mollusc

[uk-fossils]

RARE 13" Fossil Nautilus – CENOCERAS STRIATUS – Lower Sinemurian, Jurassic: Watchet, Somerset

This listing presents a RARE and EXCEPTIONAL 13-inch fossilized Nautilus (Cenoceras striatus) from the Lower Sinemurian Stage of the Early Jurassic (~199–191 million years ago). Sourced from Watchet, Somerset, UK, this specimen exhibits remarkable preservation, showcasing the characteristic smooth, coiled shell of this ancient cephalopod. A superb addition to any fossil collection, museum display, or educational exhibit!

About Cenoceras striatus:

Cenoceras is an extinct genus of nautiloid cephalopods that thrived in Jurassic seas. Unlike ammonites, nautiluses have a simpler suture pattern, reflecting their evolutionary lineage that still exists today in modern nautiluses. These ancient marine predators used jet propulsion to navigate shallow seas, hunting for small fish and invertebrates.

This well-preserved specimen from the Lower Sinemurian Stage represents an important part of Jurassic marine ecosystems, providing insight into the evolutionary history of cephalopods.

Fossil Information:

Species: Cenoceras striatus

Geological Age: Lower Sinemurian, Early Jurassic (~199–191 million years ago)

Location: Watchet, Somerset, UK

Formation: Jurassic Marine Deposits

Size: 13 inches (see photos for scale)

Condition: Excellent preservation with detailed shell structure

Why This Fossil is Special:

Authentic & Large Nautilus Fossil – A significant piece of Jurassic marine history.

Exceptional Preservation – Features well-defined shell structure and natural detail.

Highly Collectible Specimen – A perfect piece for serious collectors and museums.

From the Alice Purnell Collection – One of the largest ammonite collections in the world.

100% Genuine & Certified – Comes with a Certificate of Authenticity.

What You See is What You Get!

The fossil pictured is the exact one you will receive. We do not use stock images!

Buy with Confidence!

100% Genuine Fossils – Backed by our Certificate of Authenticity

Secure & Professional Packaging – Ensuring safe delivery worldwide

Fast & Reliable Shipping

An extraordinary fossilized nautilus, perfect for collectors, educators, and fossil enthusiasts!

[relatablemarine]

Convergent evolution is the evolution of 'analogous' or similar structures in organisms that are not closely related. Such as the wings of insects, birds and bats. One potential example of this is the Diplomoceras maximum, an extinct squid-like creature who is clearly analogous to, or a distant cousin of Clippy the paperclip. This amazing creature lived 68 million years ago, with the most notable fossil found at the cephalopod rich López de Bertodano Formation of Seymour Island, Antarctica. An area that was formerly warmer before further movement of tectonic plates. The fossil shell measured an impressive 1.5 metres and is formed from ridges, speculated to grow a section annually. These ribs are thought be similar to tree rings, being used for dating samples and gaining insight about the environment of the prehistoric sea, such as measuring the carbon and oxygen isotopes in the shell. Paleoart by James McKay

[megpricephotography]

Flynn likes to be involved with everything I do. If he sees me crouch down to look at something &/or pick it up, he likes to come & inspect it as well. In case it's interesting. Or edible. Or both.

In this case, I'd found a fossil. According to Flynn this falls in the "Not Interesting" category but he gave it a polite sniff all the same. Like I politely praise him when he finds & shows me puddles & molehills. We humour each other.

Such a teeny tiny fossil! It's one of the smallest I've found. Probably at least 420 million years old, which is just completely wild.

[swainathan]

Praise be

Omastar - Testasenex spiculum

Full print available here!

[raphlecia]

Illustration of Cretaceous Bivalvia (previously called Lamelliabranchia) by Thomas Alfred, Brock from the Monograph of Palaeontographical Society Vol. 63 (1909)

[mineralsrocksandfossiltalks]

Trivia Tuesday!

When you go bird watching all day you forget to post trivia lol.

When did ammonites first evolve? (Hint: I have given the answer in other posts)

[drhoz]

a few more fossil molluscs from NZ, that @purrdence found at a B&B on the Fossil Coast. Unfortunately she didn’t ask exactly where the owner had found them, so narrowing down an ID is beyond me, beyond two scallops and what might be a brachiopod.

[samspicturesandwords]

Molluscs may have been among the earliest life on Earth. My snails come from a line, hundreds on millions of years long, of guys who moved toward food and munched it with comical little mouths. They continue this wonderful tradition in a jar on my desk. I am proud of them.

Like this *might* be the ancestor of the guys in a jar next to me. It's from like 558-555 million years ago. "The slug-like organism fed by scratching the microbial surface on which it dwelt", just like my fellas are doing as I write this. (Image, info, & quote source: https://en.wikipedia.org/wiki/Kimberella ).

[uk-fossils]

Rare 12" Fossil Nautilus (Cenoceras striatus), Lower Sinemurian, Jurassic: Watchet, Somerset, UK

This listing presents a rare and impressive 12" fossil nautilus (Cenoceras striatus), an extraordinary specimen from the Lower Sinemurian, dating back approximately 195-200 million years to the early Jurassic period. Found in the renowned fossil-rich region of Watchet, Somerset, UK, this fossil showcases the incredible preservation of one of nature's most iconic marine creatures.

The nautilus is a marine mollusk with a coiled shell, known for its striking symmetry and chambered structure. As a relative of modern cephalopods like octopuses and squids, Cenoceras striatus provides an invaluable glimpse into the evolution of marine life. This fossilized specimen preserves exquisite details of the nautilus shell, making it a standout addition to any fossil collection.

Key Features:

Species: Cenoceras striatus (Nautilus)

Geological Formation: Lower Sinemurian

Geological Age: Early Jurassic (~195-200 million years old)

Location: Watchet, Somerset, UK

Size: An impressive 12 inches (as shown in the scale rule photograph)

Condition: Beautifully preserved with intricate details of the nautilus shell structure

Certificate of Authenticity Included:

Your purchase comes with a Certificate of Authenticity, ensuring the fossil’s provenance and authenticity. This exceptional piece originates from the highly regarded Alice Purnell Collection, renowned for housing one of the largest and most prestigious ammonite and Jurassic fossil collections in the world.

Why This Fossil Stands Out:

Exceptional Size: At 12 inches, this is a significant and rare specimen of Cenoceras striatus, ideal for display.

Historical Provenance: Discovered in the fossil-rich Watchet area, famous for its Lower Jurassic deposits.

Scientific Importance: A valuable example of a fossilized nautilus, highlighting the evolutionary history of cephalopods.

Collector's Treasure: This piece combines size, quality, and scientific value, making it a prized addition to any collection.

Perfect for Collectors, Enthusiasts, and Educators:

This stunning fossil nautilus is perfect for collectors seeking a unique and rare specimen, educators looking to inspire curiosity about Earth's ancient past, or enthusiasts wishing to own a genuine piece of Jurassic history.

Don’t miss the chance to acquire this rare and large 12" Cenoceras striatus fossil. Add this extraordinary specimen to your collection today and experience the wonder of holding a piece of prehistoric life in your hands!

All of our fossils are 100% genuine and carefully chosen pieces, ensuring quality and authenticity.

[todropscience]

THE OLDEST PREDATOR-PREY ARMS RACE UNCOVERED IN CAMBRIAN FOSSILS

A recent fossil study has revealed the oldest known evidence of an evolutionary arms race between predators and prey, dating back 517 million years to the Cambrian oceans. Researchers examined fossilized shells of Lapworthella fasciculata, a small shelled animal, and found that over 200 of them had holes likely caused by an unknown drilling predator. This predator, possibly a mollusc or soft-bodied worm, was able to penetrate the prey’s defences, triggering an adaptive response.

Interestingly, over time the shells of L. fasciculata became thicker, suggesting that the animal developed mechanisms to reinforce its shell and better withstand attacks. As shell thickness increased, so did the number of perforations, indicating that the predator also improved its ability to drill through the prey’s defences. This back-and-forth adaptation is a clear example of an evolutionary arms race, where each species evolves in response to the other in a constant battle for survival.

This discovery is crucial for understanding how predator-prey interactions drove early animal evolution, and supports the idea that predation played a key role in the diversification of biomineralizing organisms during the Cambrian explosion. Published in Current Biology, the study offers a fascinating glimpse into marine life over 500 million years ago and highlights how quickly evolutionary changes can emerge under environmental pressures.

main image: Examples of Lapworthella fasciculata shells (under scanning electron microscope) from Flinders Ranges, South Australia, showing holes made by a drilling predator. Scale bars represent 200 micrometres (0.2 mm).

Reference: Bicknell et al., 2025. Adaptive responses in Cambrian predator and prey highlight the arms race during the rise of animals. Current Biology.

[levanlanse]

♪ It's time for Fish Mollusc Fact Friday♪

Nautiluses are living fossils which have remained relatively unchanged for over 500 million years! They have multiple tentacles and unique chambered shells which they can completely withdraw into - the opening of the shells can even be covered with their hood, which is made up of two modified tentacles!

There are currently 9 living species of nautilus, and the species depicted here is the Palau Nautilus! (On a side note, there is also a species of octopus called the Paper Nautilus, despite not actually being a nautilus🐙)

[nuri148]

The fossil beaches were the main feature!

You ever think about how Mr. Darcy gets his ass absolutely destroyed by Elizabeth, immediately realizes just how much of an ass he’s been, writes a letter apologizing for what he can and explaining what he stands by, then fucks all the way off while fixing what he can for her completely anonymously without ever once expecting any sort of reconciliation let alone reward?

[mineralsrocksandfossiltalks]

FOSSIL FRIDAY: LAST OF THE AMMONITES

Today will be the last of the ammonites, the order aptly named: ammonitida.

These ammonites spanned the Jurassic and Cretaceous Periods (and possibly the earliest Paleocene before they choked and went extinct.)

This order had the most complex sutures of all the ammonites, having branching saddles and lobes that resemble manganese dendrites.

Manganese Dendrites

Ammonitida sutures

I hope this month you have learned something new about ammonites and next month we will be looking at my favorite rock formation: the Morrison Formation!

[drhoz]

#1976 - Sectipecten allani

photo by @purrdence​ at Ruakari Cave in New Zealand.

A large Oligocene scallop, first described in 1923. Apparently it can be abundant in fossil beds from that period, although individuals can vary widely in their exact shape. It appears they were derived from an Australian genus, Mesopeplum.

New Zealand is much more geologically active than Australia, with frequent volcanic eruptions, earthquakes, very large faults, and plenty of opportunity for fossil beds to be lifted above sea level and eroded into caves, for example.

[transgenderer]

Clam shrimp are a group of bivalved branchiopodcrustaceans that resemble the unrelated bivalved molluscs.[1] They are extant and also known from the fossil record, from at least the Devonian period and perhaps before.[2]

hey. whats going on with crustaceans