Ordovician sponges?

[Kane]

While splitting upper Ordovician shales in Ontario, I encountered these and reasoned it was possible these were sponges (owing to the presence of what appear to be spicules). I have encountered sponges in the upper Ordovician limestones, but not in the shales. 

 

The solo specimen measures about 1 cm. The cluster piece contain specimens slightly smaller than that. Firstly, I just wanted to rule out these as simply artifacts of mineralization. If they are sponges, I was curious if anyone had a bead on their genus as sponges are well outside my wheelhouse. 

 

[TqB]

They certainly look like it! You really need @Spongy Joe as this kind of sponge is right in his area of expertise. There are loads of genera... 

Edited May 25 by TqB

[Kane]

Thanks, Tarquin.  

For now, I have access to the Carrera and Rigby article (but just a bit lost at the moment in determining at least the type of sponge this might fall under). 

[TqB]

6 minutes ago, Kane said:

Thanks, Tarquin.  

For now, I have access to the Carrera and Rigby article (but just a bit lost at the moment in determining at least the type of sponge this might fall under). 

I've messaged Joe on social media so hope he might look in.

[doushantuo]

Perhaps Solactiniella plumata

[piranha]

 

Hinde, G.J. 1891
IV.—Notes on a New Fossil Sponge from the Utica Shale Formation (Ordovician) at Ottawa, Canada.

Geological Magazine, 8(1):22-24

 

 

Stephanella HINDE, 1891, p. 23 [*S. sancta; OD].

Circular masses of possible rhabdodiactines radiating from a center. Middle Ordovician–Upper Ordovician: Canada (Ontario), Australia (?Victoria).

——FIG. 229,1. *S. sancta, Utica Shale, Upper Ordovician, Ottawa, Canada; drawing of radial spicule structure of type (Hinde, 1891).

 

from: Treatise on Invertebrate Paleontology – Part E Porifera Revised Volume 3

[Kane]

I think we have a winner! Thanks, Scott! The description matches perfectly. 

[fifbrindacier]

That's a great ans not common find Kane, this is great !