Sponges?

[piranha]

Chonodictyon - Cretaceous-Pliocene

Farrea - Cretaceous-Pliocene

Class Demospongea

Marinduqueia - Paleocene

[Wrangellian]

Thanks Piranha, I think the Hormathospongia and Farrea are dead ringers.. some of the others you showed are pretty close too but not the same age.

I've been leaning toward 'sponge' ever since I found them and this just pushes me further. Nice to have the resources you have, up till now the closest thing I could find was 'Protospongia' from 'The Fossils of the Burgess Shale' but of course that was nowhere near the same age, and not quite the same anyway. Now I've got more ammo to show the 'experts'.

[Wrangellian]

The Cambrian sponges that come to mind are generally preserved flat like a cheesecloth. Isn't this more or less just to be expected given the age and typical characteristics of preservation? I don't mean to oversimplify the premise other than to say many Cambrian faunas yield flat fossils.

I'll post photos here of various flattened Paleozoic - Cenozoic sponges for you to evaluate in comparison with your specimens.

What I meant was that the network itself seemed to be made of a flimsy 'material' like cheesecloth, whether the whole organism was flattened or preserved in 3D. Most of the specimens I had seen up until you posted all those pics were seemingly of networks constructed of tubes (or a flat sheet with holes) rather than thin strings.

[piranha]

Thanks Piranha, I think the Hormathospongia and Farrea are dead ringers.. some of the others you showed are pretty close too but not the same age. I've been leaning toward 'sponge' ever since I found them and this just pushes me further. Nice to have the resources you have, up till now the closest thing I could find was 'Protospongia' from 'The Fossils of the Burgess Shale' but of course that was nowhere near the same age, and not quite the same anyway. Now I've got more ammo to show the 'experts'.

Glad to be of help Eric. Even more satisfying if we're able to actually identify what it is. My confidence is leaning toward one of your 'dead ringer' candidates. After a much closer inspection it would appear that Hormathospongia of the Family Farreidea is a distinct possibility. I've attached additional images and data from the treatise along with the abstract of its formal description. California certainly invites the possible occurrence of this type from your neck of the woods. You definitely have a good one Eric - BRAVO!

Abstract

An unusual Upper Cretaceous (Santonian) hexactinellid sponge from the Great Valley Sequence, western Sacramento Valley, northern California

J. Keith Rigby, Patrick Embree, and Michael Murphy Brigham Young University, Department of Geology, Provo, UT, United States

The new farreid hexactinellid sponge Hormathospongia dictyota new genus and new species, is described from the upper Santonian Dobbins Shale Member of the Forbes Formation of the Upper Cretaceous Great Valley Sequence from the west side of the Sacramento Valley, northwest of Sacramento. The relatively simple skeleton is composed of quadrangularly arranged hexactines with overlapping rays, an arrangement strikingly similar to the skeletal structure of early Paleozoic reticulosid hexactinellids. However, the California Cretaceous sponges clearly show those spicules embedded in siliceous beams that are united to form a solid dictyonal skeletal framework of only a single layer of regular mesh. Such an occurrence and stratigraphic relationships suggests that the dictyonine sponges had their origin from the simply spiculed reticulosid hexactinellids rather than from the more complex dictyosponges.

[Wrangellian]

Glad to be of help Eric. Even more satisfying if we're able to actually identify what it is. My confidence is leaning toward one of your 'dead ringer' candidates. After a much closer inspection it would appear that Hormathospongia of the Family Farreidea is a distinct possibility. I've attached additional images and data from the treatise along with the abstract of its formal description. California certainly invites the possible occurrence of this type from your neck of the woods. You definitely have a good one Eric - BRAVO!

Abstract

An unusual Upper Cretaceous (Santonian) hexactinellid sponge from the Great Valley Sequence, western Sacramento Valley, northern California

J. Keith Rigby, Patrick Embree, and Michael Murphy Brigham Young University, Department of Geology, Provo, UT, United States

The new farreid hexactinellid sponge Hormathospongia dictyota new genus and new species, is described from the upper Santonian Dobbins Shale Member of the Forbes Formation of the Upper Cretaceous Great Valley Sequence from the west side of the Sacramento Valley, northwest of Sacramento. The relatively simple skeleton is composed of quadrangularly arranged hexactines with overlapping rays, an arrangement strikingly similar to the skeletal structure of early Paleozoic reticulosid hexactinellids. However, the California Cretaceous sponges clearly show those spicules embedded in siliceous beams that are united to form a solid dictyonal skeletal framework of only a single layer of regular mesh. Such an occurrence and stratigraphic relationships suggests that the dictyonine sponges had their origin from the simply spiculed reticulosid hexactinellids rather than from the more complex dictyosponges.

Great, you're figuring this out for me, I love it! This does look like a good match, and the date is bang-on too (Upper Santonian).. I just don't have the equipment to get such a close micro view, but I might have enough to get a preliminary ID already. Maybe I should take Don's suggestion of sending the pics to Dr Rigby at BYU. Anyway, thanks again Scott! The guys in Victoria won't be able to ignore this now..

[piranha]

Great, you're figuring this out for me, I love it! This does look like a good match, and the date is bang-on too (Upper Santonian).. I just don't have the equipment to get such a close micro view, but I might have enough to get a preliminary ID already. Maybe I should take Don's suggestion of sending the pics to Dr Rigby at BYU. Anyway, thanks again Scott! The guys in Victoria won't be able to ignore this now..

It's great when everything lines up so well - I'm very glad to assist you Eric. You should definitely forward the info and images to Prof. Rigby - especially because he described/erected this new genus and species. If he's not already aware of its distribution in your region you will be providing significant new information to be included in the literature. If further investigation is called for you might have the opportunity to tag along and lead to the exact locality. Now that would be a great reward! Looks like you will have plenty to share at your next Paleo Society meeting.

Keep us posted on any noteworthy developments or feedback. Good Luck!

Edited December 8, 2010 by piranha

[Wrangellian]

It's great when everything lines up so well - I'm very glad to assist you Eric. You should definitely forward the info and images to Prof. Rigby - especially because he described/erected this new genus and species. If he's not already aware of its distribution in your region you will be providing significant new information to be included in the literature. If further investigation is called for you might have the opportunity to tag along and lead to the exact locality. Now that would be a great reward! Looks like you will have plenty to share at your next Paleo Society meeting.

Keep us posted on any noteworthy developments or feedback. Good Luck!

Will do. Do you have a complete copy of that paper and if so is there any way you could send me a copy?

An interesting tidbit I found last nite in Giovanni Pinna's Illustrated Encyclo. of Fossils is (on Hexactinellids): "Modern-day representatives of this class usually live in tropical seas at a depth between 200-500m ... [but] Many glass sponges from the Cretaceous period have been found in sediments from shallow seas and even sometimes in what were once offshore [i think they mean nearshore], or littoral environments."

I was previously thinking the spot where I found my sponges was quite a bit deeper than the outcrops further up the hill based on the assemblage there, but now it could be anything! I still think it's a little deeper than the uphill portion but maybe not by a lot.

[piranha]

Will do. Do you have a complete copy of that paper and if so is there any way you could send me a copy?

An interesting tidbit I found last nite in Giovanni Pinna's Illustrated Encyclo. of Fossils is (on Hexactinellids): "Modern-day representatives of this class usually live in tropical seas at a depth between 200-500m ... [but] Many glass sponges from the Cretaceous period have been found in sediments from shallow seas and even sometimes in what were once offshore [i think they mean nearshore], or littoral environments." I was previously thinking the spot where I found my sponges was quite a bit deeper than the outcrops further up the hill based on the assemblage there, but now it could be anything! I still think it's a little deeper than the uphill portion but maybe not by a lot.

I only have the abstract - that was the clincher for me. You can purchase the article HERE. Of all of your contacts someone must have JSTOR access. Your local library may be able to accommodate as well. If it were me on the other hand the $12 might burn a hole in my pocket.

BTW, if you acquire a pdf I would enjoy having it for my files.

Edited December 9, 2010 by piranha

[Wrangellian]

I only have the abstract - that was the clincher for me. You can purchase the article HERE. Of all of your contacts someone must have JSTOR access. Your local library may be able to accommodate as well. If it were me on the other hand the $12 might burn a hole in my pocket.

BTW, if you acquire a pdf I would enjoy having it for my files.

If I had the money to spare I'd do it, but there are so many things to buy, even just on JSTOR! Maybe someone reading this will come thru for me.....