Plantguy Posted May 20, 2018 Share Posted May 20, 2018 By any chance does anyone recognize these little orb/circular structures/features in some of the damaged Vermicularia tubes in these shots? Not sure if they might be simply immature bivalves or something else? I pried out a few of them and I'm no wiser as they are so small and I dont see any real features/markings under magnification... The two that I pried out are approx .5mm wide but the others still in the tubes are a bit bigger. The 2nd and third frames in the 2nd photo makes them look like something that could be a small echinoid with star shaped markings but that might be deceiving. they actually look more like absolutely smooth micro PVC endcaps, not spheres/orbs. In my other recent Garage finds thread Adam had a good question about operculums and I dont even know if they had one or not...So if you all have any insight I'd love to hear/know.. Thanks for the help. Regards, Chris Link to comment Share on other sites More sharing options...
doushantuo Posted May 20, 2018 Share Posted May 20, 2018 Vermiculariid gastropods do have opercula,which is not the same as saying I think these might be opercula . Link to comment Share on other sites More sharing options...
Plantguy Posted May 20, 2018 Author Share Posted May 20, 2018 1 minute ago, doushantuo said: Vermiculariid gastropods do have opercula,which is not the same as saying I think these might be opercula OK, nice. thanks. one question down... Regards, Chris Link to comment Share on other sites More sharing options...
doushantuo Posted May 20, 2018 Share Posted May 20, 2018 you might like this about 8 Mb,outtake below Link to comment Share on other sites More sharing options...
Al Dente Posted May 20, 2018 Share Posted May 20, 2018 Chris- Those are septal walls. Turritellids, Vermitellids and many fresh water snails have them. Sometimes these septa preserve better than the rest of the shell. I find little round Turritellid septa in some of the matrix I search that completely lack the rest of the shell. Link to comment Share on other sites More sharing options...
Plantguy Posted May 20, 2018 Author Share Posted May 20, 2018 1 hour ago, Al Dente said: Chris- Those are septal walls. Turritellids, Vermitellids and many fresh water snails have them. Sometimes these septa preserve better than the rest of the shell. I find little round Turritellid septa in some of the matrix I search that completely lack the rest of the shell. Fantastic! Thank you for the simple answer!!...I now want to figure out how to dissect one of these tubes to see them in cross section..am curious about how the septa are oriented...I would suspect there might be a neat spiral structure.... Regards, Chris Link to comment Share on other sites More sharing options...
Plantguy Posted May 20, 2018 Author Share Posted May 20, 2018 Well I found a larger straight section of one of these guys and tried to cut thru it with a dremel disc attachment and found out I dont have the right parts to hold it without vibration. So I tried cutting/drilling it with a micro auger shaped bit...well, I can now see the septa and how incredibly thin they are but they look like a stack of broken dishes after this evasive approach. The one shot with the red arrow shows a domed septa and the edge remains of the next broken one just on top of it. I cant imagine what trying cutting into one of the spiral tubes would be like without something with more precision like a laser. Maybe using a scope and taking it really really slow and with no depth might be more productive...I'm sure a cutaway section would be incredible looking. Another bull in a chinashop approach here but I learned something again. Thanks for the expertise @Al Dente Regards, Chris Link to comment Share on other sites More sharing options...
ynot Posted May 20, 2018 Share Posted May 20, 2018 4 hours ago, Plantguy said: Well I found a larger straight section of one of these guys and tried to cut thru it with a dremel disc attachment and found out I dont have the right parts to hold it without vibration. So I tried cutting/drilling it with a micro auger shaped bit.. Sanding with a fine grit paper (600) may give better results. Darwin said: " Man sprang from monkeys." Will Rogers said: " Some of them didn't spring far enough." My Fossil collection - My Mineral collection My favorite thread on TFF. Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted May 20, 2018 Share Posted May 20, 2018 Very interesting. It's nice to have a result on this one. Should be able to sleep tonight now. Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
Plantguy Posted May 20, 2018 Author Share Posted May 20, 2018 2 hours ago, ynot said: Sanding with a fine grit paper (600) may give better results. I plan on trying a couple more approaches and your idea sounds like one to play with. Those tubes are remarkedly pretty tough on the exterior. Interestingly most of the sections I've looked at so far actually seem to be hollow at least for a couple inches down the tube and or have sediment in them which makes me wonder. Seems like the septa in the one I already cut open were spaced very close on top of each other. If I come up with any successes I'll post the results. Thanks for the look and suggestion. Regards, Chris Link to comment Share on other sites More sharing options...
Plantguy Posted May 20, 2018 Author Share Posted May 20, 2018 1 hour ago, Tidgy's Dad said: Very interesting. It's nice to have a result on this one. Should be able to sleep tonight now. Thanks. Yes I got a couple answers but my brain doesnt work like that. Unfortunately the curiosity factor just doesnt ever stop. I was out in the rain transplanting grass and was thinking about the dumb fossi. I want to try sectioning some other larger diameter sections to see if there is a way to remove the exterior wall and somehow retain the septa. I would imagine there is an article out there on how to section gastropods...I did mess with several last year from the same spoils and had some moderate success. And lastly there is the wanting to know what one of these opercula looks like and find out if I have seen one and just overlooked it. Thanks for the looks and feedback. Regards, Chris Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted May 20, 2018 Share Posted May 20, 2018 Those cross-sections are actually pretty good. And pretty. Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
GeschWhat Posted May 21, 2018 Share Posted May 21, 2018 13 hours ago, Al Dente said: Chris- Those are septal walls. Turritellids, Vermitellids and many fresh water snails have them. Sometimes these septa preserve better than the rest of the shell. I find little round Turritellid septa in some of the matrix I search that completely lack the rest of the shell. I don't want to get too hopeful, but you may have just solved an old mystery for me. I can't tell if the septa in this thread are completely spherical or just hemispheres. Can they be spherical? A few years ago, I dissolved a Triassic coprolite fragment from the Bull Canyon Formation (freshwater floodplain) in vinegar. I found several tiny (0.5 mm dia.) spherical inclusions. I haven't found anything similar since, nor was I able to identify the inclusions. @Plantguy, do yours fizz in vinegar? You may also want to try an X-acto blade to slowly scrape off the shell layer. Lori www.areallycrappystory.com/fossils www.facebook.com/fossilpoo Link to comment Share on other sites More sharing options...
doushantuo Posted May 21, 2018 Share Posted May 21, 2018 Link to comment Share on other sites More sharing options...
Plantguy Posted May 22, 2018 Author Share Posted May 22, 2018 22 hours ago, GeschWhat said: I don't want to get too hopeful, but you may have just solved an old mystery for me. I can't tell if the septa in this thread are completely spherical or just hemispheres. Can they be spherical? A few years ago, I dissolved a Triassic coprolite fragment from the Bull Canyon Formation (freshwater floodplain) in vinegar. I found several tiny (0.5 mm dia.) spherical inclusions. I haven't found anything similar since, nor was I able to identify the inclusions. @Plantguy, do yours fizz in vinegar? You may also want to try an X-acto blade to slowly scrape off the shell layer. @GeschWhat The septa are hemispherical/semi-ovoid in shape as best I can tell from this particular section. They do fiz vigorously in vinegar! Not sure what yours is but it appears different than what I'm messing with..Yours looks oolite/ooid like, maybe even a very well rounded quartz grain? Does yours fiz? Maybe the others will offer something more definitive for you. Good luck with chasing that one down. Thanks for looking at this thread. Regards, Chris Link to comment Share on other sites More sharing options...
ynot Posted May 22, 2018 Share Posted May 22, 2018 On 5/20/2018 at 5:55 PM, GeschWhat said: I found several tiny (0.5 mm dia.) spherical inclusions. I haven't found anything similar since, nor was I able to identify the inclusions. Could it be a pearl? Darwin said: " Man sprang from monkeys." Will Rogers said: " Some of them didn't spring far enough." My Fossil collection - My Mineral collection My favorite thread on TFF. Link to comment Share on other sites More sharing options...
GeschWhat Posted May 22, 2018 Share Posted May 22, 2018 2 hours ago, Plantguy said: @GeschWhat The septa are hemispherical/semi-ovoid in shape as best I can tell from this particular section. They do fiz vigorously in vinegar! Not sure what yours is but it appears different than what I'm messing with..Yours looks oolite/ooid like, maybe even a very well rounded quartz grain? Does yours fiz? Maybe the others will offer something more definitive for you. Good luck with chasing that one down. Thanks for looking at this thread. Regards, Chris Bummer. I saw that the one you dug out was .5mm and it looked spherical and thought I might have found a match - Especially when @Al Dente said he found them without the shell (leading me to believe that perhaps they were a comprised of a more durable material. The coprolite I dissolved in vinegar fizzed (obviously), but the little spherical inclusions did not. The inclusion were uniform in size. I will have to go back and look at my notes and try to find the specimen. If I remember correctly, mine were hollow. Thank you for sharing your little experiment. It is very interesting! Lori www.areallycrappystory.com/fossils www.facebook.com/fossilpoo Link to comment Share on other sites More sharing options...
GeschWhat Posted May 22, 2018 Share Posted May 22, 2018 26 minutes ago, ynot said: Could it be a pearl? If I remember correctly, they were hollow. I originally thought they could be some sort of egg. I have a new cellular microscope. If I can find the sample, I will try to split one. Lori www.areallycrappystory.com/fossils www.facebook.com/fossilpoo Link to comment Share on other sites More sharing options...
abyssunder Posted May 22, 2018 Share Posted May 22, 2018 Hi, Chris! Good to see you again with an interesting topic here in TFF. You made a good work sectioning some of the specimens revealing the hidden things. I just see again the beautiful Vermicularia recta colony you sent me last year in May (found in the same location mentioned by you before ) and I discover, in a closer look, that almost all of the tubes have the feature you showed in your nice pics ("domed septa"). In other words, the very thin "caps" are preserved and clearly visible, especially in the narrower ends of the specimens. The shell debris (" broken dishes" as you said), infill of the tubes are fragments of the septal walls. I'm happy to have in hand a specimen like this to see exactly what is all about. Thank you again for your kindness and for the interesting thread. " We are not separate and independent entities, but like links in a chain, and we could not by any means be what we are without those who went before us and showed us the way. " Thomas Mann My Library Link to comment Share on other sites More sharing options...
doushantuo Posted May 23, 2018 Share Posted May 23, 2018 some early ontogenetic views of the septum(in the pic to the right:figs. 4-8) Link to comment Share on other sites More sharing options...
abyssunder Posted May 24, 2018 Share Posted May 24, 2018 " While septa are observed in many Paleozoic gastropod groups, they are often considered rare in modern gastropods. Notable exceptions to this statement in the literature include Turritellidae, Vermetidae, and decollate terrestrial snails. (Septa of Turritella communis were even compared with those found in Nautilus in Lyell’s Elements of Geology (1838).) Septation is, however, not rare within these groups and in fact can be found in numerous other Caenogastropod families including Cerithiidae, Muricidae, Batillariidae, Ranellidae, Caecidae and Campanilidae. This wide phylogenetic distribution of septa suggests that septa are either: 1) plesiomorphic for gastropods, or 2) frequently independently evolved, either convergently or through parallelism. Examination of septal microstructure is a first step in understanding how these structures evolved.We have examined the composition, microstructure, and patterns of septal insertion in 11 turritellid species, both fossil and Recent. Septa were found to be very thin (0.14-20 mm), with thicker septa (up to 0.80 mm) composed of multiple thin septa fused together. Number and spacing of septa was found to be highly variable among species. Septa also appear to be generated in continuity with secondary thickening of the shell wall in many species. Septa within both Turritellidae (Cerithioida) and Ranellidae (Littorinimorpha) (Bandel, 1990) appear to exhibit crossed lamellar microstructure, indicating significant energy investment by the animal. Functional significance of gastropod septa remains unclear, but possibilities include prophylaxis against apical breakage, defense against predation, response to excess calcium, or ballast. In any case, septa are not rare in gastropods. " excerpts from B. M. Anderson & W. D. Allmon. 2015. Septa aren't rare in gastropods! " We are not separate and independent entities, but like links in a chain, and we could not by any means be what we are without those who went before us and showed us the way. " Thomas Mann My Library Link to comment Share on other sites More sharing options...
abyssunder Posted May 24, 2018 Share Posted May 24, 2018 On 5/21/2018 at 3:55 AM, GeschWhat said: Can they be spherical? " Wherever the dominant shell structure is crossed lamellar, including pulmonate gastropods, septa begin as spherulitic prismatic transitioning to crossed-lamellar microstructure (Bandel, personal communication). " " We are not separate and independent entities, but like links in a chain, and we could not by any means be what we are without those who went before us and showed us the way. " Thomas Mann My Library Link to comment Share on other sites More sharing options...
Plantguy Posted May 25, 2018 Author Share Posted May 25, 2018 On 5/22/2018 at 5:26 PM, abyssunder said: Hi, Chris! Good to see you again with an interesting topic here in TFF. You made a good work sectioning some of the specimens revealing the hidden things. I just see again the beautiful Vermicularia recta colony you sent me last year in May (found in the same location mentioned by you before ) and I discover, in a closer look, that almost all of the tubes have the feature you showed in your nice pics ("domed septa"). In other words, the very thin "caps" are preserved and clearly visible, especially in the narrower ends of the specimens. The shell debris (" broken dishes" as you said), infill of the tubes are fragments of the septal walls. I'm happy to have in hand a specimen like this to see exactly what is all about. Thank you again for your kindness and for the interesting thread. Hey Lori, I thought the findings were interesting but my sectioning technique was too aggressive but I have others I might investigate with a more passive approach if I get some time. Glad you enjoy your specimen--the structures are fascinating! Regards, Chris Link to comment Share on other sites More sharing options...
Plantguy Posted May 25, 2018 Author Share Posted May 25, 2018 On 5/23/2018 at 12:14 AM, doushantuo said: some early ontogenetic views of the septum(in the pic to the right:figs. 4-8) " While septa are observed in many Paleozoic gastropod groups, they are often considered rare in modern gastropods. Notable exceptions to this statement in the literature include Turritellidae, Vermetidae, and decollate terrestrial snails. (Septa of Turritella communis were even compared with those found in Nautilus in Lyell’s Elements of Geology (1838).) Septation is, however, not rare within these groups and in fact can be found in numerous other Caenogastropod families including Cerithiidae, Muricidae, Batillariidae, Ranellidae, Caecidae and Campanilidae. This wide phylogenetic distribution of septa suggests that septa are either: 1) plesiomorphic for gastropods, or 2) frequently independently evolved, either convergently or through parallelism. Examination of septal microstructure is a first step in understanding how these structures evolved.We have examined the composition, microstructure, and patterns of septal insertion in 11 turritellid species, both fossil and Recent. Septa were found to be very thin (0.14-20 mm), with thicker septa (up to 0.80 mm) composed of multiple thin septa fused together. Number and spacing of septa was found to be highly variable among species. Septa also appear to be generated in continuity with secondary thickening of the shell wall in many species. Septa within both Turritellidae (Cerithioida) and Ranellidae (Littorinimorpha) (Bandel, 1990) appear to exhibit crossed lamellar microstructure, indicating significant energy investment by the animal. Functional significance of gastropod septa remains unclear, but possibilities include prophylaxis against apical breakage, defense against predation, response to excess calcium, or ballast. In any case, septa are not rare in gastropods. " excerpts from B. M. Anderson & W. D. Allmon. 2015. Septa aren't rare in gastropods! Thanks Ben/Lori for these references and the knowledge! Looks like I've got some more reading to do and some sectioning practice to do if I can find the time--maybe this long weekend. With the mention of the Turritellidae and other gastropod families that can be found in the Tamiami Formation I can have all kinds of fun as this curiosity expands. I give the spark/fascination due to MikeR's fantastic posts/blogs on the site and his photos of the gastropods. Its unfortunate that the major mines/shell pits in this area where these was so plentiful are now closed. They still show up in fill everywhere..I look at them in our work driveway every morning! Thanks Mike! @MikeR Regards, Chris Link to comment Share on other sites More sharing options...
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