mbarco Posted February 6, 2022 Share Posted February 6, 2022 I know how Crinoid columnals looks like, but which are the features of other echinoderm classes (Rhombifera, Diploporita,...)? Image of a crinoid columnal mould (scale bar 5mm). 2 Link to comment Share on other sites More sharing options...
Crusty_Crab Posted February 7, 2022 Share Posted February 7, 2022 (edited) I cannot emphasize enough just how useful the Treatise on Invertebrate Paleontology is for questions such as these. You can find hard copies on the secondary market for very reasonable prices. You can also join the Paleontological Society https://www.paleosoc.org/become-a-member for a very reasonable sum and get online access to all volumes of the Treatise. From Part S Echinodermata Volume 1, the Rhombifera and Diploporita are cystoids: Description of the Rhombifera: Description of the Diploporita: Edited February 7, 2022 by Crusty_Crab 1 Link to comment Share on other sites More sharing options...
Crusty_Crab Posted February 7, 2022 Share Posted February 7, 2022 Trying to read between the lines, if your question is- I found a stem, how can I differentiate between the eocrinoidea, paracrinoidea, cystoidea, blastoidea, parablastoidea, edrioblastoidea and crinoidea? The answer as I understand it is you can't, the differentiation is based on the theca. Without other information such as formation, age, etc., perhaps the best you can say is it belongs to the crinozoa. Link to comment Share on other sites More sharing options...
mbarco Posted February 7, 2022 Author Share Posted February 7, 2022 Really thanks for your answer, help & courtesy Link to comment Share on other sites More sharing options...
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