Extraordinary Common Teeth

[isurus90064]

Thanks Frank. A few more, first a matrix piece (second photo shows the shell concentration in this bed on the other side of the matrix):

 

~3.51" - 8.92cm

 

Otodus sp.

 

UG1 (see post #966)

~16.5-16 Ma

Upper Globigerina Limestone Member

Globigerina Limestone Formation

Malta

 

 

[isurus90064]

~1.56" - 3.96cm

 

Otodus sp.

 

UG2 (see post #966)

~16 Ma

Upper Globigerina Limestone Member

Globigerina Limestone Formation

Malta

 

 

[isurus90064]

~2.36" - 5.99cm

 

Otodus angustidens

 

LG (see post #966)

~24 Ma

Lower Globigerina Limestone Member

Globigerina Limestone Formation

Malta

 

[isurus90064]

Left picture, left to right:

 

~1.49" - 3.78cm

Isurus retroflexus

UG2 (see post #966)

~16 Ma

 

 

~1.82" - 4.62cm

Isurus retroflexus

UG2 (see post #966)

~16 Ma

 

 

~1.34" - 3.40cm

Isurus retroflexus

UG1 (see post #966)

~16.5-16 Ma

 

 

~1.15" - 2.92cm

Isurus retroflexus

UG2 (see post #966)

~16 Ma

 

Upper Globigerina Limestone Member

Globigerina Limestone Formation

Malta

 

 

[isurus90064]

Not a pretty tooth, but including it since it's in the fauna and it's relatively rare.

 

~1.48" - 3.76cm

 

Alopias grandis

 

UG1 (see post #966)

~16.5-16 Ma

Upper Globigerina Limestone Member

Globigerina Limestone Formation

Malta

 

[isurus90064]

For a nice comprehensive breakdown of the Malta/Gozo geology, see this link:

http://www.researchgate.net/publication/251729364_Systematics_biostratigraphy_and_evolutionary_pattern_of_the_Oligo-Miocene_marine_mammals_from_the_Maltese_Islands

"Systematics, biostratigraphy and evolutionary pattern of the Oligo-Miocene marine mammals from the Maltese Islands" - Giovanni Bianucci, Michael Gatt, Rita Catanzariti, Silvia Sorbi, Charles G. Bonavia, Richard Curmi, Angelo Varola.

[isurus90064]

Orange County geology:

 

 

"Tn" is the Niguel Formation geology shown here superimposed over Mission Viejo and Laguna Hills city streets.

 

Carcharodon carcharias

 

"Oso Parkway" - south side of Oso Pkwy. in the city of Laguna Niguel

~5 - 2.5 Ma

Pliocene

Niguel Formation

Laguna Hills

Orange County, CA

 

[isurus90064]

Back to Sharktooth Hill for a few. Starting with 4 cow sharks. As most of you know, these are hard to find whole. I'll include some of the other tooth positions later.

 

Hexanchus andersoni

 

"Sharktooth Hill"

~15.5 Ma

Middle Miocene

Roundmountain Silt

Bakersfield, Kern County

CA

 

Roundmountain Silt ages:

~15.5-16.3 Ma - Roundmountain Silt strontium-isotope ages (Olson, 1988)

~14.0-15.5 Ma - Roundmountain Silt Luisian benthic foraminiferal fauna (Barron and Isaacs, 2001; Prothero, 2001)

~15.0-16.0 Ma - Roundmountain Silt Denticulopsis lauta A zone diatoms (Barron, 1981; Barron, in Bartow and McDougall, 1984)

~14.5-16.1 Ma - magnetic stratigraphy for the Roundmountain Silt (Prothero, Sanchez, and Denke, 2008)

~15.2-16.0 Ma - magnetic stratigraphy for the middle section of the Roundmountain Silt that includes the bonebed (Prothero, Sanchez, and Denke, 2008)

~15.5 Ma - magnetic stratigraphy for the bonebed itself (Prothero, Sanchez, and Denke, 2008)

~14.5-16.1 Ma - best correlation for the Roundmountain Silt (Prothero, Sanchez, and Denke, 2008)

 

 

[isurus90064]

4 more ...

 

Hexanchus andersoni

 

"Sharktooth Hill"

~15.5 Ma

Middle Miocene

Roundmountain Silt

Bakersfield, Kern County

CA

 

 

[isurus90064]

3 more ...

 

Hexanchus andersoni

 

"Sharktooth Hill"

~15.5 Ma

Middle Miocene

Roundmountain Silt

Bakersfield, Kern County

CA

 

 

[isurus90064]

3 more ...

 

Hexanchus andersoni

 

"Sharktooth Hill"

~15.5 Ma

Middle Miocene

Roundmountain Silt

Bakersfield, Kern County

CA

 

 

[abcwixson]

I have a question after looking at both cow shark and squalicorax teeth...could either one of these be the beginning line for the tiger shark lineage...it seems the smaller blades on the cow shark could easily evolve into the wicked serrations on modern tigers...the general lean of the squali blade also could suggest an evolution to continue leaning until voila...tiger shark!!

[Auspex]

Tiger Sharks are family Carcharhinidae, Cow Sharks are Hexanchidae, Squalcorax is Anacoracidae. There is no direct link between them.

[ynot]

Here are the few Cow shark teeth (Hexanchidae) that I have from Sharktooth Hill..

Not all perfect, but it is what I have.

Tony

Edited November 12, 2015 by ynot

[isurus90064]

Very very nice ynot, thanks for posting!! There are a couple of hard to find ones in there as well.

[Coco]

Hi,

Please, put the latin names when you know them ! It is the only language which the foreigners understand to know exactly about which species you speak ! Thanks

Coco

[ynot]

Sorry Coco,

I am not very good at this yet and am trying to do better.

My last post is of a selection of Hexanchidae teeth, most likely Hexanchus andersoni.

Tony

[abcwixson]

I appreciate the answers..it was just a thought after looking at the teeth pictured above

[isurus90064]

Hexanchus andersoni - symphyseal

 

"Sharktooth Hill"

~15.5 Ma

Middle Miocene

Roundmountain Silt

Bakersfield, Kern County

CA

 

[isurus90064]

Hexanchus andersoni - symphyseal

 

"Sharktooth Hill"

~15.5 Ma

Middle Miocene

Roundmountain Silt

Bakersfield, Kern County

CA

 

[isurus90064]

Hexanchus andersoni - symphyseal

 

"Sharktooth Hill"

~15.5 Ma

Middle Miocene

Roundmountain Silt

Bakersfield, Kern County

CA

 

 

[isurus90064]

Just to consolidate with this set of pictures (posted once before, but trying to keep things a little more together). Here's a patho H. andersoni from Sharktooth Hill. This tooth is comprised of 2 teeth that have been fused together (both the root and the enamel). It also has a pathological characteristic in that the primary cusp of the distal tooth portion is upright rather than reclined distally.

 

Hexanchus andersoni

 

"Sharktooth Hill"

~15.5 Ma

Middle Miocene

Roundmountain Silt

Bakersfield, Kern County

CA

 

 

[PFOOLEY]

In looking back through this marvelous thread, I wonder...why is there not a goblet icon beneath your name?...

[abcwixson]

LOL...I agree with you PFOOLEY...his collection is absolutely jawdropping

[Auspex]

On ‎11‎/‎12‎/‎2015 at 5:55 PM, abcwixson said:

LOL...I agree with you PFOOLEY...his collection is absolutely jawdropping

The depth, breadth, connoisseurship, and commitment to quality have far surpassed the drool quotient. It is, as you note, past time to award it. Let it be so!

 

LINK