Horse Bone?

[Shellseeker]

Here is one of the finds form last weekend - a rather distinctive looking bone. A couple of month ago, I learned the word Astragalus and see that it is different.

[Auspex]

One of the sesamoids?

[tracer]

look at the os magnum, #9

[Harry Pristis]

[Shellseeker]

look at the os magnum, #9

EDIT: Add -- Thanks Harry, you added the pictures answering this query. It is Horse. I like this bone, it has character and wrinkles, almost like an Armadillo Osteoderm. end EDIT

Thank you, Thank you. and now grasshopper questions.. So I searched the Internet and found that most mammals have "os magnums". One of the early hits was THE ZOOLOGY OF THE VOYAGE OF H.M.S. BEAGLE, UNDER THE COMMAND OF CAPTAIN FITZROY, R.N., DURING THE YEARS 1832 TO 1836.

It takes me a while to catch up on my reading but 175 years is pushing it. The Beagle evidently stumbled across Camel/Llama "os magnum" and has a drawing of it.

We have camel/llama fossils in the Peace, but Equus is certainly more common. Is there anything about shape and size (50x40x10mm) that implies one type of mammal over another?

A photo of the other side:

Edited June 2, 2011 by Shellseeker

[pharoh]

shellseeker, these are some pics of my Peace River carpals and tarsals for future comparison.good luck

[pharoh]

pic #2 reverse side of same

[Harry Pristis]

EDIT: Add -- Thanks Harry, you added the pictures answering this query. It is Horse. I like this bone, it has character and wrinkles, almost like an Armadillo Osteoderm. end EDIT

Thank you, Thank you. and now grasshopper questions.. So I searched the Internet and found that most mammals have "os magnums". ...

We have camel/llama fossils in the Peace, but Equus is certainly more common. Is there anything about shape and size (50x40x10mm) that implies one type of mammal over another?

...

These ankle bones are homologs -- the same bone in different species -- but, they have a distinctive shape in each taxon. Thus, a horse magnum is easily distinguished from a camel magnum. (You don't need to write "os" with "magnum" -- we know that you are not talking about a "champagne magnum.")

I, also, am fond of these obscure little bones. I've made an effort to identify many of them, usually relying on the FSM collection. So, now I have a modest comparative collection of common (and some not-so-common) small bones.

It is a nice gesture for 'Pharoh' to post images of some of his finds, but without identifications, that is not very useful. I recommend that every vertebrate collector begin accumulating bones that you have reliably identified to eventually wind up with a useful comparative collection. (I have a few duplicates for trade to help you along.)

[Shellseeker]

Pharoh, Thanks for the comparisons. Seems like the bone I found is similar or the same to your top row, especially the top row. Like the question , I am about to ask Harry, I would be interested in your DDS -- how do you categorize and retrieve types of fossils? I am into the ziploc with a date/place in the corner of the closet mode.

Harry, Thanks..

First of all, I love the cabinet. I have something similar for modern seashells.

Second, the question I had of Pharoh. With lots of fossils, you likely require a more sophisticated method of categorization.

FSM == Florida State Museum, UF Gainesville ? If so, are you close enough to visit or is there access through the Internet?

I am slightly curious why I could search the net for "Horse OS magnum" and not find a good photo (correction TFF FoTM for May, 2011 #9 is Horse oS magnum).

I like your recommendation to have a collection of identified fossil bones, especially ones that are "interesting" I find that I can do that with more common fossils (Most Shark teeth, many Osteoderms, turtle spurs, verts) but with something like this Magnum, it is a first of the kind find for me. I am still not positive that it is Horse, or Camel/Llama, or something else. especially if you compare it to FoTM for May, 2011.

I do know light years more stuff by reading and asking questions on this forum for the last 20 months. and I thank you for your contributions to my fossil education,

Edited June 3, 2011 by Shellseeker

[Harry Pristis]

...

Harry, Thanks..

First of all, I love the cabinet. I have something similar for modern seashells.

Second, the question I had of Pharoh. With lots of fossils, you likely require a more sophisticated method of categorization.

FSM == Florida State Museum, UF Gainesville ? If so, are you close enough to visit or is there access through the Internet?

I am slightly curious why I could search the net for "Horse OS magnum" and not find a good photo (correction TFF FoTM for May, 2011 #9 is Horse oS magnum).

I like your recommendation to have a collection of identified fossil bones, especially ones that are "interesting" I find that I can do that with more common fossils (Most Shark teeth, many Osteoderms, turtle spurs, verts) but with something like this Magnum, it is a first of the kind find for me. I am still not positive that it is Horse, or Camel/Llama, or something else. especially if you compare it to FoTM for May, 2011.

I do know light years more stuff by reading and asking questions on this forum for the last 20 months. and I thank you for your contributions to my fossil education,

In the past, I always visited the museum to see the fossils for myself. It makes me uneasy to accept an identification without evidence (sometimes, that is unavoidable).

The cabinets I have were originally designed as shell cabinets. I had them custom-built with drawers of varying depth. They have a glass-covered well in the top for some specimens.

You'll always be confused if you believe that the May FoTM is a horse magnum. It appears to be a pisiform bone. You can search the TFF archives for a "quiz" thread on these pisiforms.

Learning is what it's all about. No one can take away what you store in your head. But, it's nice to have a "thank you"!

[Brandy Cole]

@Harry Pristis

 

I'll throw my thanks into the mix too.  I was completely lost when I started, and your BONES collection here was an invaluable teaching resource.

[fossillarry]

It's an ectocuneiform from the hind foot of a horse. This bone supports the navicular above which supports the astragalas and it overlies the third metatarsal.

[Shellseeker]

 

On 6/11/2022 at 9:28 PM, Brandy Cole said:

@Harry Pristis

 

I'll throw my thanks into the mix too.  I was completely lost when I started, and your BONES collection here was an invaluable teaching resource.

Brandy,

Fossillarry is absolutely correct.  This bone that I found 11 years ago is not a Equus Carpal Magnum, but a Tarsal Ectocuneiform. Hard to believe it took so long to get a correct ID. You should be building a very good small bone "comparison box".   Jack

Edited June 17, 2022 by Shellseeker

[Harry Pristis]

1 hour ago, Shellseeker said:

 

Brandy,

Fossillarry is absolutely correct.  This bone that I found 11 years ago is not a Equus Carpal Magnum, but a Tarsal Ectocuneiform. Hard to believe it took so long to get a correct ID. You should be building a very good small bone "comparison box".   Jack

  Oh, my!

  Jack, my image of "horse ectocuneiform" is correctly labelled.   Your comparison is not correct.  Good image, wrong label. 

  What your image depicts is an Equus NAVICULAR.  One simple way to distinguish between the two bones is the degree of dishing of the articular surfaces.  The ectocuneiform has MOL flat articulations with the proximal and distal sides in parallel.  In contrast, the navicular has one side (the distal, I think) notably curved or "dished out."  This dished out contour is quite evident in your image.

 

[Shellseeker]

2 hours ago, Harry Pristis said:

  Oh, my!

  Jack, my image of "horse ectocuneiform" is correctly labelled.   Your comparison is not correct.  Good image, wrong label. 

  What your image depicts is an Equus NAVICULAR.  One simple way to distinguish between the two bones is the degree of dishing of the articular surfaces.  The ectocuneiform has MOL flat articulations with the proximal and distal sides in parallel.  In contrast, the navicular has one side (the distal, I think) notably curved or "dished out."  This dished out contour is quite evident in your image.

 

Harry,

I would be the 1st to agree that Tarpal/Carpal identification are very difficult. Most bones we find as Florida fossils do not resemble other bones at all .  Think Astragalus and Calcaneum, no one will mistake one for the other. 

Then consider this thread. As a relatively novice fossil hunter, I started the description with "A couple of month ago, I learned the word Astragalus and see that it is different." In 2011, I had never seen or found or knew the name of a "ectocaneiform" or a "navicular".

 

1) Auspex indicated it  was a sesamoid,  and Tracer indicated I should look at  Equus "OS Magnum"

2) You provided a picture of all the Equus Carpals and Tarsals, which included a Carpal "Magnum"

At this point, I believed it to be an Equus Magnum, and provided a closeup of the opposite side.

3) Pharoh provided photos of Equus ??? Carpals and Tarsals and yes indeed, the center top one seemed to look exactly like my Magnum.

4) In the May 2011 FoTH submissions, Whowat13 submitted a Bone from the Peace river that he identified as an Equus Magnum,  that you identified as a Pisiform bone in this thread.

 

So that is the way I left this thread 11 years ago, believing my find was an Equus Magnum,  and so when a New thread had a broken Equus Tarsal/Carpal for identification. Call it Thread A request by jbenton.

http://www.thefossilforum.com/index.php?/topic/123948-peace-river-find-what-is-it/

and I pointed to this thread suggesting it might be a Magnum.

 

That , after 11 years, allowed Fossillarry to correctly (I think) to identify this old fossil ID request as a Tarsal Ectocuneiform !!!  I think he is correct , but that is a long time to wait for a fossil ID.

 

Note also 8 months ago, I incorrectly identified an Equus Navicular as an Equus Ectocuneiform in a TFF thread. If I had access to your clear statements in your post above, I would not have done so. I accept your definition of significant differences between Ectocuneiforms and Naviculars.

 

So the best answer to jbenton's Fossil ID -- Thread A

 

It seems that there are 3 somewhat or very similar horse bones (Ectocuneiform, Navicular, and Magnum) that require discussion of differences in order to correctly identify each. Here are some of those differences. You should search TFF for photos of each, and compare your fragment to those photos, and decide what is closest. 

 

I have always felt it is preferable to keep the discussion going on the chance someone new to fossil hunting might get another answer to a Fossil ID request. Some of them may read this thread and not make the same mistakes I do. They will know how to differentiate Ectocuneiform, Navicular, and Magnum without my help

 

[Harry Pristis]

I'm sorry for your confusion, Jack.  I can understand how these intercalated threads and faulty guesses could have contributed.  I thought I had shed light into the darkness with the line drawings of horse ankle bones.  I see now that I will have to make images of the three bones that have been most troublesome.  I have extras of all these bones and many others -- they have been a special interest of mine for a looong time.  

[Shellseeker]

4 minutes ago, Harry Pristis said:

I'm sorry for your confusion, Jack.  I can understand how these intercalated threads and faulty guesses could have contributed.  I thought I had shed light into the darkness with the line drawings of horse ankle bones.  I see now that I will have to make images of the three bones that have been most troublesome.  I have extras of all these bones and many others -- they have been a special interest of mine for a looong time.  

You are a treasured resource on this forum.  Thanks for all you do. Jack

[fossillarry]

Thank you Shellseeker for putting up pictures of equid naviculars and  ectocuneiform.

[Harry Pristis]

Here we go!  I doubled up on the ectocuneiform 'cause that one seems to be most troublesome:

 

 

[JohnJ]

Well done!  Thanks, Harry.

[Sanja]

Good day, I'm not sure if this horse bone is magnum or ectocuneiform.. Magnum I think it looks different, I'll post a picture. However echtochuneiform is liitle bit different so it is not clear to me

[Harry Pristis]

Sanja . . .

Welcome to the Forum.  Your find most resembles a magnum, but I'm not sure it is from a horse.  Better focused images might help with an identification.

[Sanja]

Thank you very much!

 

Maybe these photos are a little better. I also have a bone that I believe is a magnum. These are the remains of the hipparion horse.

[Sanja]

The fourth picture shows the magnum