Show us your Desmostylus fossils

[Bobby Rico]

North Pacific Rim's Desmostylus, is a goofy toothed mammal, which belongs to a group with no close living relatives. Because it is unlike any living mammal, palaentologists have had a hard time figuring out its lifestyle.

 

The Desmostylia are weird and mystifying creatures . Basically they are only found from deposits of the Late Oligocene and the Miocene. Desmostylus is assigned to four genera that have only been found in Japan and along the west coast of Mexico and the United States, to as far north as Washington.

 

Fossils of Desmostylus were first described in 1888 by Othniel Marsh, from marine deposits collected in Alameda County, California. The fossils were considered to represent Sirenians, and subsequent fossils found in Japan were interpreted as possibly being primitive elephants or Sirenians (sea-cows).

 

The bizarre Desmostylians has some unique physical features, such as the teeth that show pattern of wear in their enamel that are not observed in any modern mammal, and science is not yet certain just what these short-tusked, shovel-jawed animals ate. The most compelling evidence suggests they were herbivores.

Comparisons have been made between desmostylians and the hippopotamus but i just read their lifestyle may have been more like that of the sea lions. I don't know if this means they ran on the bottom of the sea like a hippopotamus or swam like a sea lions? This creature I feel has still some understanding to be uncovered. 

 

So show us your Desmostylus martial. 

 

American Museum of Natural History NY

 

Desmostylus reconstruction. Image: K.Matsui/Smithsonian. Institution.

Edited January 10 by Bobby Rico

[Bobby Rico]

Desmostylus hesperus mammal unerupted molar. 

Location: Temblor Formation, California

Approximate age: Temblor Formation, Miocene, (~15.5 Million Years)

[jpc]

Here are mine....

 

 

 

(subtle joke.. I have none)

 

But I would love to see more desmos.  Such weird teeth and beasts.

Edited January 10 by jpc

[Harry Pristis]

Here's one:

 

[opalbug]

Here is a few pics of Desmostylus molars that a friend found as float in the beach gravel.

From the Miocene, Nye Mudstone, Lincoln County, Oregon, USA

 

Edited January 10 by opalbug

[Tidgy's Dad]

I have a few little bits sent to me by Doren.

So they are very special to me.

[Bobby Rico]

13 hours ago, Tidgy's Dad said:

a few little bits sent to me by Doren.

So they are very special to me.

Thanks for adding them Adam and the same goes for me. Doren was my secret santa one year, when Parker run it. He sent me a big box of goodies but he had forgot to add some partial desmostylus teeth ( they was listed). Before I even received my first christmas box he messaged me say he had forgot to add the desmostylus teeth and would be send a another box of goodies including them. He was not very good at the secret bit of the secret santa but a great gift giver . I sent him one of my favourite ammonites as a thank you. I don't know about you but I never heard of Desmostylus before Doren introduced me.

Edited January 11 by Bobby Rico

[Bobby Rico]

@Harry Pristis @opalbug thanks both for adding these beautiful fossil much appreciated.  Cheers Bobby 

[Tidgy's Dad]

3 hours ago, Bobby Rico said:

 I don't know about you but I never heard of Desmostylus before Doren introduced me.

 

Yeah, I didn't either.

Always nice to learn new things, especially about such a weird beastie. (Desmostylus, not Doren.)

[siteseer]

Hi Bobby,

 

Yes, I've always thought Desmostylus and related genera were among the most interesting extinct mammals I'd heard of.  If you look at early restorations of Desmostylus as it might have looked alive, you see them drawn as having flippers and a tail like a dugong.  I don't think it was known to have legs and feet until the 1950's. 

 

I started collecting fossils in the late 80's and used to see these teeth for sale at the Tucson and Denver shows, and being in California, I'd see them at local shows as well.  Some of the dealers I met then (and became old friends later) were people who personally collected a lot of teeth at the Fresno County locality back in the 70's and 80's.  A couple of them would have a table covered with specimens at the beginning of a show and they'd be gone by the end, some specimens reappearing at other shows while others went into personal collections.  Sometime in the early 90's, I heard the landowner stopped allowing collecting.  I also heard that the layer was dipping in a way that made the digging more difficult as well so the older diggers moved on to other areas for other fossils.  Either way, by the mid-90's you might have seen maybe just a few teeth total at a big show and then they became rare sights anywhere by the late 90's.

 

There used to be a rock shop in Sunnyvale, CA (Santa Clara County) that was also a Western Union.  The owner was a retired USGS geologist and I sometimes hung out there during part of my lunch hour and talk to him about fossils.  I worked in the mall across the street at the time.  He hunted around the Desmostylus site back in the 60's and still had a pickle jar full of partial teeth that he found as float.  They were just the tubular cusps that form the crown, tending to separate sometime after final deposition.  Doren kept the cusps he found in the Sharktooth Hill Bonebed and that Monterey County locality because even a piece of a tooth is much rarer find where Desmostylus occurs outside of that Fresno County locality.  I dug at various STH sites for years and found just one tooth (a couple of partial cusps still collected) in all that time and I kept that for the same reason. 

 

A rare find even at the Fresno County locality is a tooth of another desmostylian, Palaeoparadoxia.  The teeth are very similar to its relative but the crown is more cup-like and the cusps seem to grow from it rather than the cusps forming the crown themselves.  In recent years , a new genus was erected, Neoparadoxia, to include at least one species once assigned to Palaeoparadoxia.

 

Anyway, I used to have several Desmostylus teeth but sold or traded them across the years and just have a few now.  I have just a couple of Palaeoparadoxia teeth.  I'll get them photographed maybe this week.  In the meantime here are a few photos of a Desmostylus tooth I still happen to have.  It was interesting to me for its unusually-small size and uneven wear pattern (a nice little matrix piece too).

 

Jess

 

 

 

 

[Bobby Rico]

On 2/25/2024 at 5:00 AM, siteseer said:

Jess

Hi Jess, please except my apologies on the very late response.  Thanks for the insight in the collecting desmostylus fossils , I found it very interesting.  You got a nice specimen there. Cheers Bobby .