They went through the window screen (STH)

[Malone]

11 minutes ago, ynot said:

A couple of fish(?) teeth.

Notice the distinct cutting edge, it is present on both sides of both teeth.

The tips look almost like removable caps.

[ynot]

A fish bone and a fish vert....

[ynot]

And a few more fish teeth...

 

That is all for now.

More to follow?

[siteseer]

On March 28, 2018 at 7:29 PM, MarcoSr said:

 

Tony

 

I'm not sure about the first tooth labeled as Gymnura based upon the views in the two pictures.  It could be Mobula.  Mobula have lots of variation in their teeth.  The second specimen labeled as Gymnura definitely looks like Gymnura.

 

Here is one type of Mobula tooth that looks similar to that first tooth.:

 

 

The first Scyliorhinus labeled tooth looks like another Triakis tooth to me.

 

Marco Sr.

 

Hi Marco Sr.,

 

I agree that the tooth marked as a Scyliorhinus is a broken Triakis.  There are catsharks in there, though.  They are in that 1-2mm range and have a more delicate-looking form with a higher cusp and higher lateral cusplets.  I have one maybe two but not a way to photograph it. 

 

Catsharks are rare even when screening for the tiny size because they have apparently frequented deeper water across their time on earth dating back to the Cretaceous.  I should add that as more people have been screening over the past 20 or so years, more teeth are being noticed.  It appears a lot of paleontologists didn't start screening for micros until maybe the 1960's.

 

Jess

 

 

[ynot]

1 hour ago, siteseer said:

 

Hi Marco Sr.,

 

I agree that the tooth marked as a Scyliorhinus is a broken Triakis.  There are catsharks in there, though.  They are in that 1-2mm range and have a more delicate-looking form with a higher cusp and higher lateral cusplets.  I have one maybe two but not a way to photograph it. 

 

Catsharks are rare even when screening for the tiny size because they have apparently frequented deeper water across their time on earth dating back to the Cretaceous.  I should add that as more people have been screening over the past 20 or so years, more teeth are being noticed.  It appears a lot of paleontologists didn't start screening for micros until maybe the 1960's.

 

Jess

 

 

Hey hi Jess,

There were 2 teeth marked as Scyliorhinus sp. in the original posting and Marco"s comment was about the first of the 2 pictured teeth.

Are You saying that neither tooth is a Scyliorhinus sp. ?

 

I thought they were cat based on the difference in the cusp placement, the indentation on the labial side at the base of the crown and lack of striations in this area.

 

Tony

[sixgill pete]

Tony, great post. I have been a big fan of micro's for several years, but you have brought things to a new level. I normally do not screen any smaller than .50 mm. Maybe I should have gone smaller with my STH matrix. Your photography is great. I really like the variety of the fish teeth you found. There is quite a variety in the matrix we get here from Lee Creek, but very little of it is identified. 

[ynot]

On 4/9/2018 at 2:59 PM, siteseer said:

Edit:  After looking through my collection, I found a parasymphyseal which is similar but is higher than it is wide.

Like this one?

[ynot]

13 minutes ago, sixgill pete said:

Tony, great post. I have been a big fan of micro's for several years, but you have brought things to a new level. I normally do not screen any smaller than .50 mm. Maybe I should have gone smaller with my STH matrix. Your photography is great. I really like the variety of the fish teeth you found. There is quite a variety in the matrix we get here from Lee Creek, but very little of it is identified. 

Thanks.

I know nothing about the fish teeth, but it is a nice variety of types.

I have found a wide variety in the lee creek matrix too.

It is amazing what can come out of this stuff. Who would think that fish verts would be in this small of a matrix, but they are common (most are just half).

[MarcoSr]

14 hours ago, siteseer said:

 

Hi Marco Sr.,

 

I agree that the tooth marked as a Scyliorhinus is a broken Triakis.  There are catsharks in there, though.  They are in that 1-2mm range and have a more delicate-looking form with a higher cusp and higher lateral cusplets.  I have one maybe two but not a way to photograph it. 

 

Catsharks are rare even when screening for the tiny size because they have apparently frequented deeper water across their time on earth dating back to the Cretaceous.  I should add that as more people have been screening over the past 20 or so years, more teeth are being noticed.  It appears a lot of paleontologists didn't start screening for micros until maybe the 1960's.

 

Jess

 

 

 

Jess

 

I looked through my pictures of STH specimens and don't have a picture of a Scyliorhinus tooth.  I have looked through a good bit of fine STH matrix over the years and not having a single picture tells me that they are not found that often in the fauna.  At some point I'll check my STH micros for Scyliorhinus specimens but I have many thousands of micros so it may take a while to go through them.

 

Marco Sr.

[MarcoSr]

12 hours ago, ynot said:

Like this one?

 

Tony

 

All shark teeth on either side of the symphysis can technically be called parasymphyseal by the broadest definition of parasymphyeal if the left/right side dentitions are symmetrical.  However this tooth isn't a parasymphyseal, like the other tooth that you posted, by the much narrower definition of smaller (than the first anterior tooth), matching teeth just on either side of the jaw mid-line.

 

Marco Sr.

[siteseer]

On April 11, 2018 at 3:36 PM, ynot said:

Hey hi Jess,

There were 2 teeth marked as Scyliorhinus sp. in the original posting and Marco"s comment was about the first of the 2 pictured teeth.

Are You saying that neither tooth is a Scyliorhinus sp. ?

 

I thought they were cat based on the difference in the cusp placement, the indentation on the labial side at the base of the crown and lack of striations in this area.

 

Tony

 

Hi Tony,

 

Yeah, I don't think they're catsharks.  The teeth I have considered catshark were about 2mm high, had more slender crowns, higher labial folds, widely-branching root lobes, and a prominent lingual protuberance.  That's not say that all catsharks of that area and that time would look like that with all those characters.  That's just what the few I've seen looked like.  A few years ago, someone here posted a photo of an STH microand asked what it was.  I thought it was close to Cephaloscyllium.  Unfortunately, that photo appears to have been lost when the site went down sometime since then.  I have a line drawing of a Cephaloscyllium tooth somewhere and will try to find and scan it.

 

Scyliorhinid teeth have been reported from the bonebed.  Applegate (in Mitchell, 1965) noted three scyliorhinids including Cephaloscyllium and Scyliorhinus but did not figure any specimens.

 

Yeah, it appears catsharks are rare not just because you would find them only through screening but because they didn't frequent the STH environment  (and still don't).  The East Pacific swell shark does live in warm, shallow water but among rocky reefs around kelp beds but its Miocene relative appears to have been smaller and may have preferred a different environment.

 

The two other known modern catsharks off California frequent cooler, deeper water than afforded in the STH environment.  It's not a slam-dunk but it indicates that their ancestors preferred a different environment than what was available in the Bakersfield area during the Middle Miocene (relatively shallow, warm-temperate conditions).

 

Jess

 

Mitchell, E. 1965. 

History of research at Sharktooth Hill - Kern County California.  Kern County Hist. Society, CA. 45pp.

 

 

 

[ynot]

1 hour ago, siteseer said:

Yeah, I don't think they're catsharks. 

Oh well, the search goes on....

 

Thank You for the descriptive instruction, now I know what to look for.

 

Respectively.

Tony 

 

PS Found a beautiful little Raja, with roots, today. (Will try to get a picture up tomorrow.)

[ynot]

21 hours ago, ynot said:

Found a beautiful little Raja, with roots, today.

And I lost it.

 

But here are a few others....

Scale is in millimeters.

Raja sp.

 

Mobula  sp.

 

[ynot]

There were a lot of ball shaped teeth.

Here is a group picture.

 

Then there were a lot of cone (straight and curved) in the mix.

 

 

A few close ups of the "cone" teeth...

[ynot]

More fish teeth...

[ynot]

[ynot]

[ynot]

[ynot]

 

Well that is pretty much all I have found so far.

Hope Y'all liked the show.

Regards,

Tony

[Mike from North Queensland]

I liked the show and you got some wonderful micro teeth. 

One question though, Is what you showed from a single small volume of the parent sample or a concentration from a full bucket to get the amount of specimens.

 

Mike

 

 

[ynot]

2 hours ago, Mike from North Queensland said:

I liked the show and you got some wonderful micro teeth. 

One question though, Is what you showed from a single small volume of the parent sample or a concentration from a full bucket to get the amount of specimens.

 

Mike

 

 

Hey Mike,

Thanks.

I kept some of the matrix that went through the window screen when I processed the first batch of micro matrix I collected at sharktooth hill. Had about 10 gallons of this fine sand. 

I then screened it with a much finer screen. After I had done that I had about 3 gallons of material. 

I have searched about 4 cups worth, but showed less than half of the finds.

I got lucky and had some rich matrix to start with.

 

Tony

[ynot]

Thought I should add these to this thread...

Unidentified fish teeth (?)

And a posterior mako/white shark tooth.

[ynot]

A couple more fish teeth....

[MarcoSr]

On 5/19/2018 at 9:22 AM, ynot said:

Hey Mike,

Thanks.

I kept some of the matrix that went through the window screen when I processed the first batch of micro matrix I collected at sharktooth hill. Had about 10 gallons of this fine sand. 

I then screened it with a much finer screen. After I had done that I had about 3 gallons of material. 

I have searched about 4 cups worth, but showed less than half of the finds.

I got lucky and had some rich matrix to start with.

 

Tony

 

Tony

 

I really like the diversity of specimens that you found in that very fine matrix.  You definitely had some very rich matrix.  It takes a lot of patience to search that very fine matrix and to take all of the great pictures that you did.  Thank you for this post.

 

Marco Sr.

[ynot]

1 minute ago, MarcoSr said:

 

Tony

 

I really like the diversity of specimens that you found in that very fine matrix.  You definitely had some very rich matrix.  It takes a lot of patience to search that very fine matrix and to take all of the great pictures that you did.  Thank you for this post.

 

Marco Sr.

Thanks Marco!

I greatly appreciate the acknowledgement.