Back in New Zealand

[Doctor Mud]

Also came across this:

 

 

It was split on it on one side already - by someone else? Exposing a bit. I wasn't sure I was seeing what I thought it was so split off a little. Bits re attach really well here.

 

Any guesses what it is?

[Doctor Mud]

Close ups of the exposed bits:

 

[Ludwigia]

Sorry I can't help you any further, but now I'm really curious. That last crab also looks good, by the way.

[Doctor Mud]

7 hours ago, Ludwigia said:

Sorry I can't help you any further, but now I'm really curious. That last crab also looks good, by the way.

 

Thanks Ludwigia.

It survived the split ok. I split these big concretions as it is a painful hike out and I want to be sure.

 

I know what the mystery object is, I just wanted see if anyone could guess what it is 

[6ix]

Vertebra?  looks like a mini stargate.. 
 

 

[Doctor Mud]

52 minutes ago, 6ix said:

Vertebra?  looks like a mini stargate.. 
 

 

 

 

"What is this.....A STARGATE FOR ANTS??!!"

 

[Doctor Mud]

@6ix is on the money.

 

Another shark vert, and a very large one!

About 17 cm across or 7 inches.

 

Looks like someone split it and saw it wasn't a crab and discarded it......

 

 

[6ix]

Meg?

[Doctor Mud]

17 minutes ago, 6ix said:

Meg?

 

Definitely a good candidate! I think only Megs, basking sharks and Whale Sharks have such big verts.

I think there are ways to tell the difference between the verts. I remember seeing a paper on the subject a while back...... now where did I put it?

 

@Dave (POM) Allen Have you found any large shark verts up your way? I know of one other large shark vert from the Miocene in New Zealand.

A small string of large verts was also found in the North Island, but I think it is Cretaceous?

[Doctor Mud]

Just found the paper I was talking about about basking shark vs Carcharocles verts.

 

Miocene basking sharks (Lamniformes: Cetorhinidae) from the Chesapeake Group of Maryland and Virginia. 

MD Gottfried - Journal of Vertebrate Paleontology, 1995

 

Excerpt from this paper follows:

 

"DISTINGUISHING CENTRA OF CETORHINUS FROM CARCHARODON

 

Bartsch and Barwick (1941) evidently based their assignment of USNM 16365 and 16366 to Carcharodon megalodon on the basis of the specimens' large size and the fact that C. megalodon teeth are regularly found in the same Miocene deposits [note: some authors, including Cappetta, 1987, assign the giant-toothed shark species megalodon to the genus Carcharoc/es Jordan and Hannibal, 1923 ; the more traditional assignment of this form to Carcharodon , the genus that includes the extant Great White Shark Carcharodon carcharias, is followed here for reasons outlined in Gottfried et al., in press). Cetorhinus is not mentioned in Bartsch and Barwick's paper and apparently was not considered a possibility. While the centra of these two lamniform genera share similarly large size and an ovoid outline, they are different enough in more specific features that they can be readily distinguished from one another and from other large sharks (see also Kozuch and Fitzgerald, 1989). In comparison to Carcharodon, Cetorhinus has more elongate centra with thin and rather flaky walls that generally do not preserve, leaving only the cones. Cetorhinus centra also possess a distinct oval perforation through the middle, as described in the fossil specimens above. Carcharodon centra do not have a central perforation, and typically have preserved centrum walls and well-developed septae. The relatively short centra of Carcharodon have shallow biconcavities on their articular surfaces, while Cetorhinus centra are more deeply biconcave and form two distinct cones that meet at their apices. Proportional differences in the centra of the two genera are reflected in vertebral counts for the extant species: 170-187 in Carcharodon carcharias vs. 109-116 in Cetorhinus maximus (Gottfried et aI., in press). The double cones comprising Cetorhinus centra are easily separated, while Carcharodon centra are more compactly and solidly constructed."

[Dave pom Allen]

3 hours ago, Doctor Mud said:

 

Definitely a good candidate! I think only Megs, basking sharks and Whale Sharks have such big verts.

I think there are ways to tell the difference between the verts. I remember seeing a paper on the subject a while back...... now where did I put it?

 

@Dave (POM) Allen Have you found any large shark verts up your way? I know of one other large shark vert from the Miocene in New Zealand.

A small string of large verts was also found in the North Island, but I think it is Cretaceous?

 

 

taranaki vert,also have seen very large verts bigger than yours from mt cass i assume thats where yours is from

http://pukeariki.com/Learning-Research/Taranaki-Research-Centre/Taranaki-Stories/Taranaki-Story/id/555/title/they-grew-em-big-in-times-gone-by#

[Doctor Mud]

2 hours ago, Dave (POM) Allen said:

 

 

taranaki vert,also have seen very large verts bigger than yours from mt cass i assume thats where yours is from

http://pukeariki.com/Learning-Research/Taranaki-Research-Centre/Taranaki-Stories/Taranaki-Story/id/555/title/they-grew-em-big-in-times-gone-by#

 

Thanks Dave,

 

This was the only other one I knew of and seen photos of from the Miocene of New Zealand.

 

It is touted as a meg vert but I am sceptical. This one is not 100% from C. Megalodon. 

 

If you use the formulae of Gottfried and Shimada (both very similar) and the largest size of a great white (6.4 m), this Taranki vert would give a shark of 6.6 m. So could still just be a large great white. The argument is that this vert is from the tail. This vert is 11 cm diameter.

The largest I've found is 17 cm diameter. Not prepped yet, but would be a 10 m long shark.

 

If you believe that megs got up to 20 m long (based on teeth) verts could be twice this size! Would love to see others found from Canterbury, hopefully a tooth or teeth will show up. I've heard of large worn teeth from these deposits, but not 100% megs since no serrations survived.

[Dave pom Allen]

i have seen leigh loves verts, in waipara. they are very large from mt cass he also has teeth

[Doctor Mud]

49 minutes ago, Dave (POM) Allen said:

i have seen leigh loves verts, in waipara. they are very large from mt cass he also has teeth

 

Would love to see them one day. How big do you think the verts and teeth were?

Were the teeth from Mt Cass, on the beach in the siltstone concretions?

[Doctor Mud]

On 1/8/2018 at 11:18 PM, Dave (POM) Allen said:

i have seen leigh loves verts, in waipara. they are very large from mt cass he also has teeth

Thanks for the info Dave.

 

I got in touch with him and had a chat about his collection. Very interesting man to talk to.

Going to visit him later this week.

 

Cheers mate!

 

[Doctor Mud]

Funny thing about this site is it seems to be the reverse of the usual situation. Verts are much more common than teeth.

 

Could it be because fluids produced by decay are necessary to help concretion formation? So a vert or string of verts with flesh attached is more likely to be preserved?

 

So far I've found 16 shark verts in four separate concretions and only one partial tooth - unfortunately not a meg.

 

I've seen concretions containing multiple teeth @Dave (POM) Allen has found one....... (has that been prepped? would love to see it). 

 

Do you find many teeth up in Taranaki?  Any megs yet?

[6ix]

@Doctor Mud - can we post a photo of the first prepped vert?

[Plax]

On 1/9/2018 at 9:06 PM, Doctor Mud said:

Funny thing about this site is it seems to be the reverse of the usual situation. Verts are much more common than teeth.

 

Could it be because fluids produced by decay are necessary to help concretion formation? So a vert or string of verts with flesh attached is more likely to be preserved?

 

So far I've found 16 shark verts in four separate concretions and only one partial tooth - unfortunately not a meg.

 

I've seen concretions containing multiple teeth @Dave (POM) Allen has found one....... (has that been prepped? would love to see it). 

 

Do you find many teeth up in Taranaki?  Any megs yet?

teeth are usually concentrated in lag deposits (as clasts like pebbles). Verts, bones and invertebrates are found loose in sediment and also concentrated in lags a bit. Erosion forms a sort of lag deposit (cliff / ocean interface) also so that teeth can be concentrated of course. A sequence break above your formation, at some other locality, should produce a lag. That lag should include the resistant clasts derived from the erosion of the formation below.

[MeargleSchmeargl]

Can't wait to see that shark material prepped!