Monica Posted September 2, 2018 Share Posted September 2, 2018 Hello there! I was able to visit Hungry Hollow's South Pit (near Arkona, Ontario, Canada - age is mid-Devonian) yesterday - boy was it hot!!! Viola and I spent three hours surface-collecting before we decided to call it quits and head to our air-conditioned car. We found our usual stuff, but I'd like your input on the following two items: Item #1 front and back: a type of Favosites coral - perhaps placenta? It's a lot flatter than my other Favosites finds, and you can even see what I think are some crinoid holdfasts on top, and an echinoderm plate (perhaps from a crinoid calyx?) on the back!!! Item #2 front and back: I have NO idea whatsoever!!! It's smooth, and I can't see evidence of holes/pores, but it is kind of hilly - what do you think? Thanks in advance for your help!!! Monica 4 Link to comment Share on other sites More sharing options...
piranha Posted September 2, 2018 Share Posted September 2, 2018 26 minutes ago, Monica said: Item #2 front and back: I have NO idea whatsoever!!! It's smooth, and I can't see evidence of holes/pores, but it is kind of hilly - what do you think? Stromatoporoid? 3 Link to comment Share on other sites More sharing options...
piranha Posted September 2, 2018 Share Posted September 2, 2018 Stromatoporella elevata appears to be a possible candidate. text from: Galloway, J.J. & Ehlers, G.M. 1960 Some Middle Devonian stromatoporoids from Michigan and southwestern Ontario, including the types described by Alexander Winchell and A.W. Grabau. Contributions from the Museum of Paleontology the University of Michigan, 15(4):39-120 PDF LINK Remarks. -Winchell's specimen of S. elevata is attached to a fragment of an orthoconic cephalopod which was obtained from a dark-gray limestone. The specimen is dark buff-gray. The smooth shiny surface of the coenosteum between the pustules is due to the lack of granules, papillae and ring pillars, structures that appear at the surface of many species. Some specimens of S. elevata that occur in the Thedford-Arkona region of Ontario, Canada, are attached to corals (Heliophyllum, Alveolites, and Emmonsia) and others spread over the original calcareous mud of the sea bottom. The Ontario specimens are light-buff. Some specimens from that region have one or more pores at the summit of a pustule. Occurrence. -S. elevata is abundant in the coral bed of the Middle Devonian Hungry Hollow formation exposed at Hungry Hollow in the Ausable River Valley about 2 miles east of Arkona and in the same bed shown in the tileyard about one-half mile north of Thedford. 6 Link to comment Share on other sites More sharing options...
Innocentx Posted September 2, 2018 Share Posted September 2, 2018 Your 1st one shows possibilities of being chaetetid sponge. It's a beautiful piece with it's holdfasts. 1 "Journey through a universe ablaze with changes" Phil Ochs Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted September 2, 2018 Share Posted September 2, 2018 Beautiful Favosites with holdfasts, really lovely. (sorry, not sure of the species found there). And the stromatoporoid is a good find too! 2 Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
Monica Posted September 2, 2018 Author Share Posted September 2, 2018 Oh, wow - if this is indeed a stromatoporid (and it's looking pretty good - thanks @piranha!), then it'll be my first!!! YAY!!!!!!!!!! As for the first item - is there any way to determine which crinoid(s) the holdfasts belong to? Thanks again! Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted September 2, 2018 Share Posted September 2, 2018 2 minutes ago, Monica said: Oh, wow - if this is indeed a stromatoporid (and it's looking pretty good - thanks @piranha!), then it'll be my first!!! YAY!!!!!!!!!! As for the first item - is there any way to determine which crinoid(s) the holdfasts belong to? Thanks again! You may get lucky and find one that exactly matches, but with the Wenlock ones that I've been studying recently, it's not even possible to say if it's a crinoid for sure, they could be other stalked echinoderms like blastoids. 1 Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
Innocentx Posted September 2, 2018 Share Posted September 2, 2018 Maybe a close up of the hold fast would reveal something. If there's no detail of crinoid it might be of bryozoan. 1 "Journey through a universe ablaze with changes" Phil Ochs Link to comment Share on other sites More sharing options...
Dan 1000 Posted September 3, 2018 Share Posted September 3, 2018 Sorry I can’t be of much help but nice finds, especially the stromatoporoid 1 Link to comment Share on other sites More sharing options...
FranzBernhard Posted September 3, 2018 Share Posted September 3, 2018 I would have never guessed that #2 is a stromatoporid. From the photo, I would have said its some calcium carbonate deposition in a crack. Already learned something today! Btw, I like your #1 very much! Very nice specimen! Franz Bernhard 1 Link to comment Share on other sites More sharing options...
Ludwigia Posted September 3, 2018 Share Posted September 3, 2018 6 hours ago, Monica said: As for the first item - is there any way to determine which crinoid(s) the holdfasts belong to? Thanks again! I can't say for certain, but I do know that Arthroacantha carpenteri is the most common crinoid there. 2 Greetings from the Lake of Constance. Roger http://www.steinkern.de/ Link to comment Share on other sites More sharing options...
Wrangellian Posted September 3, 2018 Share Posted September 3, 2018 Lovely Favosites, and congrats if that turns out to be your first stromatoporoid! 1 Link to comment Share on other sites More sharing options...
crinus Posted September 4, 2018 Share Posted September 4, 2018 Favosites placenta for sure. Also definitely a stromatoporid. I haven't a clue as to what species. Definitely echinoderm holdfasts. Impossible to tell which crinoid/blastoid. I can say for sure that they are not Arthroacantha holdfast. Don't see what you are referring to as a calyx on the back. I see one plate of a crinoid calyx and it looks like an Arthroacantha plate. I wish I had my stromatoporid back that I donated to a museum. It was huge and I spent hours cleaning it but it was tooooo big for any of my cabinets so I donated it. Wish it was back in my collection. You can see it here http://www.michiganbasinfossils.org/viewrecord/23 Joe 2 Link to comment Share on other sites More sharing options...
Innocentx Posted September 4, 2018 Share Posted September 4, 2018 @crinus. Nicely done. 1 "Journey through a universe ablaze with changes" Phil Ochs Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now