Strange fossil i found today at Big Brook, NJ

[75millionyearsago]

Found this strange fragment of cretaceous cephalopod- i found many others today, and in the past as well. However this one had a strange fragment that has been fossilized within. I cannot identify it, nor figure out why it is inside this small bit of cephalopod cast. It is rock hard, and i cannot break or bend the bits off that are sticking out. 

[Mahnmut]

Sorry I cannot help with the ID, but I am very curious to hear what others will say. 

Looks like some kind of parasite to me (or a piercing ;)  )

very intriguing find!

Best Regards,

J

[Darktooth]

These are belemite pieces.

[Tidgy's Dad]

Yes, I agree. 

The first one has a cone shaped hollow because this is the alveolus where the phragmocone would have fitted.

[Tidgy's Dad]

Oh, I see what you mean. 

The larger piece is a rock stuck in the alveolus, but you are referring to the little black tube that seems to run through the calcite of the alveolus wall? 

Interesting. 

Yes, maybe a parasite or a piece of worm tube or the like which the alveolus grew around? 

[Mahnmut]

30 minutes ago, Tidgy's Dad said:

Yes, I agree. 

The first one has a cone shaped hollow because this is the alveolus where the phragmocone would have fitted.

9 hours ago, 75millionyearsago said:

Found this strange fragment of cretaceous cephalopod- i found many others today, and in the past as well. However this one had a strange fragment that has been fossilized within. I cannot identify it, nor figure out why it is inside this small bit of cephalopod cast. It is rock hard, and i cannot break or bend the bits off that are sticking out. 

 

Yes, but did you see the dark double wire-like intrusion into the smallest piece? I think thats what the OP is asking about.

 

[75millionyearsago]

1 hour ago, Tidgy's Dad said:

Oh, I see what you mean. 

The larger piece is a rock stuck in the alveolus, but you are referring to the little black tube that seems to run through the calcite of the alveolus wall? 

Interesting. 

Yes, maybe a parasite or a piece of worm tube or the like which the alveolus grew around? 

Yep, thats what i was referring to. Its quite strange. Certainly atypical for a Belemnitella Americana. Whatever it was had to have been within the belemnite when it died, right? It’s been fossilized together, after all.

[75millionyearsago]

1 hour ago, Mahnmut said:

Yes, but did you see the dark double wire-like intrusion into the smallest piece? I think thats what the OP is asking about.

 

Correct- sorry i was unclear, i already ID’d the species, the other speciments were just for example and comparison to the unique one. 

[Tidgy's Dad]

7 minutes ago, 75millionyearsago said:

Yep, thats what i was referring to. Its quite strange. Certainly atypical for a Belemnitella Americana. Whatever it was had to have been within the belemnite when it died, right? It’s been fossilized together, after all.

Yes, I think it was present in the calcite before death, though I suppose it is possible that something burrowed into it post mortem but before fossilization. 

It's Belemnitella americana, by the way. Species names are never capitalized even if it is the name of a country or person. 

Tarquin knows a bit about belemnites. @TqB

Seen anything like this before, old chap? 

Edited June 22, 2023 by Tidgy's Dad

[TqB]

1 hour ago, Tidgy's Dad said:

@TqB

Seen anything like this before, old chap? 

I think the form genus might be Trypanites  which bores rocks, hardgrounds and sometimes belemnites. In some formations, borings in belemnites are virtually the norm and are generally considered to be post mortem, partly because the rostrum is covered with soft tissue in life. I guess it's unusual in Big Brook specimens.

[75millionyearsago]

4 hours ago, TqB said:

I think the form genus might be Trypanites  which bores rocks, hardgrounds and sometimes belemnites. In some formations, borings in belemnites are virtually the norm and are generally considered to be post mortem, partly because the rostrum is covered with soft tissue in life. I guess it's unusual in Big Brook specimens.

Any idea why the borings are filled in, solid bits, rather than the typical holes i’d expect? Or is there any shot its something more along the lines of a parasite? 

[TqB]

25 minutes ago, 75millionyearsago said:

Any idea why the borings are filled in, solid bits, rather than the typical holes i’d expect? Or is there any shot its something more along the lines of a parasite? 

It looks as if it could be pyrite whose formation is often initiated by decay of soft parts.

Parasite is certainly possible but has rarely been demonstrated. You'd need to see some deformed growth of the rostral layers in response to it. That might show obviously or might need microscopic views of sectioned material (or CT scan!).

As this paper says, "For belemnites, most reported pathologies are due to survived predator attacks..., a few malformations are assigned to the activity of parasites."
Non-destructive analysis of pathological belemnite rostra by micro-CT techniques