Jump to content

Starfish Fossil?


WestOz64

Recommended Posts

So a rock saw would end this debate? Saw a 5 cm thick slab off the rock parallel to the exposed surface. If the fossil is a starfish it would not be harmed and would be thinned to the point where you could hang it on your wall for display. If it is still present on the cut surface, then you'll have a clean, unweathered cross-section of an Evactinopora to show. Is that right?

Absolutely.

Link to comment
Share on other sites

I understand what you are saying Piranha. I'm saying the reason your expert used for disqualifying the first fossil from being Evactinopora is invalid. They can have little relief and still be Evactinopora as we have seen with the other examples.

Although three experts have weighed in, two of them have only offered a cursory assessment, in contrast to the most informative analysis offered by Dr. Jell in his detailed technical description on the original posted specimens seen in the attached image. Whether or not certain preservational features are consistent across the range of all the fossils posted in this thread, is interesting of course, but really a separate matter entirely.

IMG1.jpg

image.png.a84de26dad44fb03836a743755df237c.png

Link to comment
Share on other sites

I sent an email to Dr Jell, offering to take photo's of more specimens and also to send him an actual specimen. The specimen in the photo above, is in a rock 40cm x 40cm x 15cm deep, so fairly weighty, I have offered to try and find one on a smaller piece if he would like me too, but as our average temperature is 43 degree's at the moment, I also told him, he would have to wait a couple of months until it cool's down a bit. Or he can have the specimen above if he wants it....but he can pay the postage!!! :D

Link to comment
Share on other sites

I sent an email to Dr Jell, offering to take photo's of more specimens and also to send him an actual specimen. The specimen in the photo above, is in a rock 40cm x 40cm x 15cm deep, so fairly weighty, I have offered to try and find one on a smaller piece if he would like me too, but as our average temperature is 43 degree's at the moment, I also told him, he would have to wait a couple of months until it cool's down a bit. Or he can have the specimen above if he wants it....but he can pay the postage!!! :D

Thank you for contacting Dr. Jell and your kind generosity to make these fossils available for further evaluation. Regardless of the outcome, it's been an interesting and informative exercise to say the least. I hope the large starfish he said might be related to Palaeaster, turns out to be a new species named in your honor. Good luck and please keep us posted on all the details as they become available.

image.png.a84de26dad44fb03836a743755df237c.png

Link to comment
Share on other sites

I have hesitated to weigh in on this debate, because being a newbie, I actually know bugger all......but if the word "flat" in the sentence below is being used in this context ie 'you can run your hand over the rock and not feel anything raised'

One cannot make the argument that fossil #1 is not Evactinopora because it is flat, then say the others can be Evactinopora even though they are flat.

Then I must say, that the fossils in the pic's below are definitely not flat, nor are the many other bryozoa fossils around here. Perhaps because I photographed them from directly above, it hasn't shown their true nature.

post-14076-0-10056100-1391911535_thumb.jpg

post-14076-0-64115900-1391911562_thumb.jpg

Link to comment
Share on other sites

Received an email from Dr Jell this morning:

Many thanks for your email response. Sorry I have not responded earlier but was away last week and am just catching up with a pile of emails on this bright Monday morning.

I am very jealous of you being within easy reach of the Callytharra Formation –I have been through there collecting on several occasions but never seem to have enough time. I have collected in the south around Callytharra itself (where I found 1 good starfish over and above those described by Kesling some time ago ) then come north to Gascoyne Junction, where I found several in the river bed. From there north we usually came past Lyons River and turned off at Mount Sandiman to follow the Kennedy Range up to Williambury. I spent several days scouring the range just west of Williambury but found only crinoids (no starfish). So your new site for starfish is very important to my study of Australian fossil starfish. I attach a few examples of different specimens from different parts of Australia to show you the sort of material I am working with. I would be very interested to see the specimen in the photograph and any others you may locate in future.

I am committed to a finishing a paper on some Victorian trilobites for a memorial volume to a Chinese palaeontologists with whom I worked over a 25 year period from about 1980 and who died recently. I shall also be out of Australia for the month of July but I could possibly make a trip over your way in late August or September to see your specimens and do some field work as well. Would that timing be convenient for you??

The best book on the fossils of your area is Bulletin of the Geological Survey of Western Australia. No. 136 (Permian palaeontology of Western Australia). It is available through the Geological Survey of Western Australia website but you may have to purchase a paper copy as I cannot see an electronic version there. If you send me your postal address I can send my publications on the crinoids of the area.

Once again, thanks for your email. I hope this information is of some help and I look forward to meeting up with you later in the year, if possible.

Best wishes

Peter Jell

So it looks like we will have to wait until August/September, to see what the good doctor has to say when he see's the specimens in the flesh (so to speak!) I have attached the pic's he sent.

post-14076-0-07575500-1392002626_thumb.jpg

post-14076-0-02905500-1392002654_thumb.jpg

post-14076-0-01970000-1392002679_thumb.jpg

Link to comment
Share on other sites

hi,

Marvelous ! You are finally going to know about what it is on behalf of a specialist. Very beautiful collaboration between an amateur and a scientist.

Coco

----------------------
OUTIL POUR MESURER VOS FOSSILES : ici

Ma bibliothèque PDF 1 (Poissons et sélaciens récents & fossiles) : ici
Ma bibliothèque PDF 2 (Animaux vivants - sans poissons ni sélaciens) : ici
Mâchoires sélaciennes récentes : ici
Hétérodontiques et sélaciens : ici
Oeufs sélaciens récents : ici
Otolithes de poissons récents ! ici

Un Greg...

Badges-IPFOTH.jpg.f4a8635cda47a3cc506743a8aabce700.jpg Badges-MOTM.jpg.461001e1a9db5dc29ca1c07a041a1a86.jpg

 

Link to comment
Share on other sites

  • 2 weeks later...

Peter Jell just sent me this email. Looks like Al Dente gets all the kudos for this ID, Congrats! :fistbump:

I am most grateful for your sending the photograph of the second specimen. The higher magnification in this image allowed me to see the details of the specimen and I have to report some bad news (depending on whether you like echinoderms or bryozoans) which then became apparent. The two specimens you have photographed are not starfish but are fossil bryozoan colonies. They belong to a species that is known in the Callytharra Limestones of your area and was named Evactinostella crucialis by Huddleston in 1883 in the Journal of the Geological Society of London. The colony of bryozoans was tall with a vertical central spindle from which emanated four (and sometimes 5 or 6) lateral flanges. When a weathered cross section is exposed, as in your specimens, it looks remarkably like a starfish. The pitting on the first specimen that I took to be receptacles for spine bases are the apertures of the individual polyps that make up the colony. The individual polyps are also seen as the transverse lines across the flanges from the centreline to the margins. This also explains why the central body plating looked wrong for a starfish but now that I recognise it the central disc is exactly as seen in other specimens of Evactinostella. The occurrence of 5-rayed forms is not so common but now that you know what they are I feel confident that you will find 4-rayed specimens in the same area. Though disappointing for my current starfish study this correction to the identification does not diminish their importance and I shall still be aiming to visit later in the year as I mentioned earlier. Apologies for my earlier misidentification and I hope you do turn up some starfish which we know lived in the rocks of your district. The riverbed at Gascoyne Junction downstream to Jimba Jimba is a well-known locality for them so happy hunting.

Best wishes

Peter Jell

image.png.a84de26dad44fb03836a743755df237c.png

Link to comment
Share on other sites

Whew! I have been holding my breath for the resolution, one way or another. Scott, your unflagging efforts have once again won the Forum the final truth about a very enigmatic fossil. Well done!

"There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant

“Try to learn something about everything and everything about something.” - Thomas Henry Huxley

>Paleontology is an evolving science.

>May your wonders never cease!

Link to comment
Share on other sites

congratulations to Al Dente, and Scott also, thanks, for following through so well :)

"Your serpent of Egypt is bred now of your mud by the operation of your sun; so is your crocodile." Lepidus

Link to comment
Share on other sites

Hi all....just received a second email from Dr Jell, if anyone would like a copy of the Huddleston paper, I can email a pdf (5.22mb) to you, or is there somewhere on this site to upload it ?

"Further to my email of a few moments ago I went and found a copy of Huddleston’s paper (attached) because I had remembered he talked a fair bit about the Kennedy Range area which I thought might interest you. You can see on his plate he has figured the 4-rayed form of crucialis. You will note he assigned it to the North American (Mississippi Valley) genus Evactinopora but Joan Crockford who studied a wide range of Australian bryozoans during the 1940s and 50s recognised it to be a distinct genus and she introduced the name Evactinostella for the species in 1957."

Cheers :)

Link to comment
Share on other sites

Whew! I have been holding my breath for the resolution, one way or another. Scott, your unflagging efforts have once again won the Forum the final truth about a very enigmatic fossil. Well done!

Thanks Auspex :) my sentiments exactly.

There are over 2300 views on this excellent post. A lot for me to learn.

Thanks to WestOZ64 for sharing your finds. Great Job Al Dente, you have an amazing eye for detail.

It's hard to remember why you drained the swamp when your surrounded by alligators.

Link to comment
Share on other sites

  • 8 months later...

'Brittle Star'!

Not.

You should read the whole discussion.

"There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant

“Try to learn something about everything and everything about something.” - Thomas Henry Huxley

>Paleontology is an evolving science.

>May your wonders never cease!

Link to comment
Share on other sites

I missed it as well. Great reading and deduction!

"A problem solved is a problem caused"--Karl Pilkington

"I was dead for millions of years before I was born and it never inconvenienced me a bit." -- Mark Twain

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...