Rick_Jo Posted August 16, 2013 Share Posted August 16, 2013 Does anyone know what this is? These small fossils (size 7-10mm) are from the Braxton Formation in the Maitland Group based of the Sydney Basin somewhere during the mid Permian. The formation is marine, below wave base and the majority of the fossils found are brachiopods and flourishing bryozoans. I was fortunate enough to visit the site on the weekend and am currently going through my fossil finds photographing and ID-ing. I have not seen this before. Link to comment Share on other sites More sharing options...
Fossildude19 Posted August 16, 2013 Share Posted August 16, 2013 They are an odd shape, aren't they? To me, they look like misshapen crinoid columnals. Weird. Regards, Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 __________________________________________________ "In every walk with nature one receives far more than he seeks." John Muir ~ ~ ~ ~ ><))))( *> About Me Link to comment Share on other sites More sharing options...
Indy Posted August 16, 2013 Share Posted August 16, 2013 I agree ...Similar to a Platycrinites saffordi crinoid stem segmentLink Flash from the Past (Show Us Your Fossils)MAPS Fossil Show Link to comment Share on other sites More sharing options...
fossilcrazy Posted August 16, 2013 Share Posted August 16, 2013 I agree with Indy. The oblong shape allows the "stem" to spiral. Link to comment Share on other sites More sharing options...
Mr. Edonihce Posted August 16, 2013 Share Posted August 16, 2013 Ya, that's what I'm thinking as well.Here's why...* grooves on outer end of each one look like the crenella that help the individual columnals stay in place on the crinoid's column* dot/point/knob in the very middle of each one seems like the ossicle's lumen which, together, make up the crinoid's axial canalThe main thing that throws us off is the fact that, for the most part, the individual ossicles of a crinoid column are usually circular, whereas these (if that's what they are) are oval. Given the fact that all of the pieces are oval, individually, I'm inclined to think that they were so in life as well (or at lesat that somethig happened to the crinoid immediately prior to final burial).It seems like, if it were a normal-shapped column (with circular ossicles), whatever pressure came upon them would have squished them all in the same direction, and they'd all be arranged similarly, but they are all as if they were oval prior to burial here, by the way they are all sitting in different directions/orientations.If anyone has a good explanation for how they could all get 'squished' like this (or if you happen to know iof a species that grew oval-shaped columnals), please do tell. . ____________________ scale in avatar is millimeters ____________________ Come visit Sandi, the 'Fossil Journey Cruiser' ____________________ WIPS (the Western Interior Paleontological Society - http://www.westernpaleo.org) ____________________ "Being genetically cursed with an almost inhuman sense of curiosity and wonder, I'm hard-wired to investigate even the most unlikely, uninteresting (to others anyway) and irrelevant details; often asking hypothetical questions from many angles in an attempt to understand something more thoroughly." -- Mr. Edonihce Link to comment Share on other sites More sharing options...
Mr. Edonihce Posted August 16, 2013 Share Posted August 16, 2013 I agree ... Similar to a Platycrinites saffordi crinoid stem segment Link I agree with Indy. The oblong shape allows the "stem" to spiral. Doh, I missed both of those posts because I was still typing. :lol: . ____________________ scale in avatar is millimeters ____________________ Come visit Sandi, the 'Fossil Journey Cruiser' ____________________ WIPS (the Western Interior Paleontological Society - http://www.westernpaleo.org) ____________________ "Being genetically cursed with an almost inhuman sense of curiosity and wonder, I'm hard-wired to investigate even the most unlikely, uninteresting (to others anyway) and irrelevant details; often asking hypothetical questions from many angles in an attempt to understand something more thoroughly." -- Mr. Edonihce Link to comment Share on other sites More sharing options...
Indy Posted August 16, 2013 Share Posted August 16, 2013 Not suggesting what you found is a Platycrinites just pointing out all crinoid stems are not round. Platycrinites Link Flash from the Past (Show Us Your Fossils)MAPS Fossil Show Link to comment Share on other sites More sharing options...
TqB Posted August 16, 2013 Share Posted August 16, 2013 I've come across similar crinoid ossicles in the Brigantian (U. Mississippian) in northern England - I've mislaid the specimen but here's a pic, the ossicle is about 5mm across the long axis. Sorry, no name for it! Tarquin Link to comment Share on other sites More sharing options...
BobWill Posted August 16, 2013 Share Posted August 16, 2013 I certainly don't have a better idea than crinoid but can anyone see crenella groves on both sides of any of those? The groves seem to curve around the ends of the ovals but I'm unable to see any with groves going down the opposite side. This could just be a trick of the light or angle of the photo... Link to comment Share on other sites More sharing options...
Ridgehiker Posted August 16, 2013 Share Posted August 16, 2013 (edited) Not sure. We find fossiliferous plates from the Tournasian with similar type shapes. Sometimes blastoids in the matrix. The Blastoids are not studied (they aren't in most places) but are similar to 'Schizoblastus'. This blastoids type extends into the Permian. Anyways it looks a bit like a side plate from a disarticulated schizoblastus-type blastoid. All speculation. If this is something from the Echinodermata it should be calcite and the calcite crystal surface should be reflective if wetted and held at a horizontal angle to the light.. Edited August 16, 2013 by Ridgehiker Link to comment Share on other sites More sharing options...
piranha Posted August 16, 2013 Share Posted August 16, 2013 Although these crinoid ossicles have not been officially recorded in the Branxton Formation they are described from the lateral eqiuvalent Berry Siltstone. Attached are some examples of Neocamptocrinus for comparison. The specialist on this material has suggested Neocamptocrinus bundanoonensis to be the likely species for the posted examples. Congrats on a great discovery! Willink, R.J. (1980) A new coiled-stemmed camerate crinoid from the Permian of eastern Australia. Journal of Paleontology, 54(1):15-34 5 Link to comment Share on other sites More sharing options...
BobWill Posted August 16, 2013 Share Posted August 16, 2013 Great find and ID! So it wasn't a trick of the light. Now I'm very curious to know why grooves were not needed on both sides. It doesn't seem likely they would be worn off with such regularity so they must have grown that way Link to comment Share on other sites More sharing options...
piranha Posted August 16, 2013 Share Posted August 16, 2013 On 8/16/2013 at 0:24 PM, BobWill said: Great find and ID! So it wasn't a trick of the light. Now I'm very curious to know why grooves were not needed on both sides. It doesn't seem likely they would be worn off with such regularity so they must have grown that way According to the paper: "For convenience the side of the stem facing the axis of coiling will be termed the inner side, and that facing away from the axis, the outer side. Columnar articular facets consist of: 1) a fulcral ridge oriented parallel to the long axis of the facet; 2) a very small (<1 mm diameter) circular lumen, the external expression of an axial canal, located medially on the fulcral ridge; 3) two shallow, semi-circular areolar areas (bifascial fields), one on either side of the fulcral ridge; and 4) a crenularium along the inner facet perimeter whose culmina are closely spaced, moderately high and vary in length according to position." 2 Link to comment Share on other sites More sharing options...
Mr. Edonihce Posted August 16, 2013 Share Posted August 16, 2013 (edited) My take = coiled-stemmed crinoids developed the coiling tendency as a means of helping them wrap around another object.Simple example with our own bodies...If you put your two hands together with the fingers interlocking (um....the traditional 'prayer' pose), it is still possible to move the proximal ends of your hands side to side, whereas, for the most part, the portion of the hands from the start of the fingers on out are sort of locked in place. If the 'free' end of the hand was then connected to a locked end of another, there could be a very flexible structure, even though it were still a stack of hands connected by a central axis. I don't know if that's really what they were trying to say there or not, but it makes sense to me.What I want to know is how the crenulated sides are organized. Is it always on the same side, so that one entire hemisphere of the column is like this, or does it alternate from one side to the other from one columnal to the next?It would seem to result in a more flexible structure, overall, if it was alternating. Otherwise, it would seem to only allow the column to flex in one plane.Don't mind me.....I'm just thinking out loud.... Edited August 16, 2013 by Mr. Edonihce . ____________________ scale in avatar is millimeters ____________________ Come visit Sandi, the 'Fossil Journey Cruiser' ____________________ WIPS (the Western Interior Paleontological Society - http://www.westernpaleo.org) ____________________ "Being genetically cursed with an almost inhuman sense of curiosity and wonder, I'm hard-wired to investigate even the most unlikely, uninteresting (to others anyway) and irrelevant details; often asking hypothetical questions from many angles in an attempt to understand something more thoroughly." -- Mr. Edonihce Link to comment Share on other sites More sharing options...
Rick_Jo Posted August 19, 2013 Author Share Posted August 19, 2013 Thank you to everyone for helping me solve this, I have learnt much about crinoids and ossicles in the process. If anyone is interested in learning more about the 'Permian fossils and palaeoenvironments of the northern Sydney Basin' I have included a link to an interesting publication. I read it before visiting the site and should have investigated it further as it does mention crinoids such as Neocamptocrinus sp., I was always under the impression that crinoid ossicles where round, not anymore. thanks again Link to comment Share on other sites More sharing options...
Rick_Jo Posted August 19, 2013 Author Share Posted August 19, 2013 http://www.resources.nsw.gov.au/extras/quarterly_notes/00138-permian-fossils Link to comment Share on other sites More sharing options...
Indy Posted August 19, 2013 Share Posted August 19, 2013 Thank you to everyone for helping me solve this, I have learnt much about crinoids and ossicles in the process. If anyone is interested in learning more about the 'Permian fossils and palaeoenvironments of the northern Sydney Basin' I have included a link to an interesting publication. I read it before visiting the site and should have investigated it further as it does mention crinoids such as Neocamptocrinus sp., I was always under the impression that crinoid ossicles where round, not anymore. thanks again Most crinoid stems are round... however some have different shapes. Flash from the Past (Show Us Your Fossils)MAPS Fossil Show Link to comment Share on other sites More sharing options...
izak_ Posted November 27, 2014 Share Posted November 27, 2014 Yeah, i agree it could be a crinoid column. Link to comment Share on other sites More sharing options...
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