Any Porifera People Out There?

[I_gotta_rock]

I pulled this out of the Mahantango Formation of Pennsylvania a couple weeks ago. It's middle Devonain. TI though as I pulled it out of the scree that it was more of the myriad corals, but looking at it more closely it is most certainly not (although there are a couple Rugosa tucked in there), the structure is all wrong. I was told by one sponge enthusiast that it is definitely sponge. some kind of sponge.

I'm a taxonomist at heart, and it drives me nuts if I can't at least narrow something down to a family. The literature on porifera is woefully scant, especially on this coast. Looking at the steinkerns in the holes, it looks like a network of narrow tubes rather than the pores of one big sponge wall. Could this be Amphiporidae? Anyone have any good references?

 

[Tidgy's Dad]

From this angle it looks more like a syringoporid coral to me. 

Is there any detail visible on the sides? 

Edited April 12, 2022 by Tidgy's Dad

[DPS Ammonite]

Sponges rarely have such sharp edges. I see exterior molds of rugose corals with rugae or wrinkles. The positive cylindrical structures (one is labeled: filling) are the fillings of the top or interior of corallites. Syringoporoid is a good guess.

I bet that the rock is chert since the original corals have dissolved away.

Edited April 12, 2022 by DPS Ammonite

[Tidgy's Dad]

18 minutes ago, DPS Ammonite said:

Sponges rarely have such sharp edges. I see exterior molds of rugose corals with rugae or wrinkles. The positive cylindrical structures (one is labeled: filling) are the fillings of the top or interior of corallites. Srygoporoid is a good guess.

The Syringoporidae are a family of tabulate corals. 

If it is a colonial rugose coral, something like Acinophyllum might be a better fit. 

[DPS Ammonite]

4 minutes ago, Tidgy's Dad said:

The Syringoporidae are a family of tabulate corals. 

If it is a colonial rugose coral, something like Acinophyllum might be a better fit. 

Adam, is correct about rugose vs tabulate corals; thanks. I still see molds of corals that might be a syringoporoid.

[I_gotta_rock]

2 hours ago, Tidgy's Dad said:

From this angle it looks more like a syringoporid coral to me. 

Is there any detail visible on the sides? 

Unfortunately, not yet. A profile view would be helpful.

I was thinking about finding a club mate with a rock saw who can slice it for me.

[I_gotta_rock]

50 minutes ago, DPS Ammonite said:

Sponges rarely have such sharp edges. I see exterior molds of rugose corals with rugae or wrinkles. The positive cylindrical structures (one is labeled: filling) are the fillings of the top or interior of corallites. Syringoporoid is a good guess.

I bet that the rock is chert since the original corals have dissolved away.

I'll have to see what I can get for a closer look. This might be it. The matrix isn't chert, it's mudstone, very soft when wet.

[Tidgy's Dad]

1 minute ago, I_gotta_rock said:

Unfortunately, not yet. A profile view would be helpful.

I was thinking about finding a club mate with a rock saw who can slice it for me.

Yes, maybe carefully cut and polish one of the ends. 

[I_gotta_rock]

1 minute ago, Tidgy's Dad said:

Yes, maybe carefully cut and polish one of the ends. 

Polishing probably won't happen unless I use acrylic. It's mudstone. When it's wet, it smashes with a hammer rather than breaking.

 

[Plax]

These may have all been attached as in Coenites but we're only looking at the broken ends. I suspect that corals are aragonitic so they have been selectively been dissolved away from the mud stone leaving remnants. The site near Berwick had them that way.

[I_gotta_rock]

2 minutes ago, Plax said:

These may have all been attached as in Coenites but we're only looking at the broken ends. I suspect that corals are aragonitic so they have been selectively been dissolved away from the mud stone leaving remnants. The site near Berwick had them that way.

Yes, that is part of the problem. The preservation at this locality is an interesting mix. The strata are arranged on a 45 degree angle, layered N to S. At the north end, everything is pyritized. a bit south, it's just molds and steinkerns, and further south still the calcium carbonate is intact. My luck, this came from the impressions-only area.

[abyssunder]

Teredolites (or related) ichnofossil(s)?

[Plax]

13 hours ago, abyssunder said:

Teredolites (or related) ichnofossil(s)?

I was thinking the same thing except I don't recall gastrochaenolites or such in the Devonian. 

[I_gotta_rock]

I don't remember gastrochaenites in the Devonian, either. Mollusks I am familiar with, although more in the Cretaceous and Cenozoic. Also, there is no evidence that the "burrows" were in anything but mud.

 

Glad I'm not the only one puzzled by these! Thanks for the ongoing help, all!

[Plax]

I'm still liking partially dissolved away coenites and that we aren't easily seeing the branching aspect in this particular rock.

[abyssunder]

7 hours ago, I_gotta_rock said:

I don't remember gastrochaenites in the Devonian, either. Mollusks I am familiar with, although more in the Cretaceous and Cenozoic. Also, there is no evidence that the "burrows" were in anything but mud.

 

Glad I'm not the only one puzzled by these! Thanks for the ongoing help, all!

There are similar borings in mud made by wasps in the Cenozoic. Are you sure about the geological age?

[I_gotta_rock]

3 hours ago, abyssunder said:

There are similar borings in mud made by wasps in the Cenozoic. Are you sure about the geological age?

Positive.

[I_gotta_rock]

And the verdict is Syringeopora coral.