paleoflor Posted April 23, 2015 Share Posted April 23, 2015 Hi all, The photograph below shows a specimen, collected at the Piesberg quarry, which I am trying to identify, and therefore I would like your thoughts on the following: To me, the large size of the pinnules (scale = 4 cm) immediately suggests Macroneuropteris. However, it is difficult to assign the overall shape of the pinnules (triangular and markedly broad) to any particular species within this genus. Browsing the literature, I came across Cleal et al. 1996, which describes the frond architecture for M. macrophylla. On the basis of their specimens and frond-reconstruction (modified version used with photo below), one could hypothesize that my specimen from the Piesberg shows the imprints of some basal pinnules, which are situated on the frond below the main bifurcation (see yellow accent in schematic figure). This would also be in line with the occurrence and orientation of the three partial "regular" pinnules on the top right of the sample. However, the only species of Macroneuropteris of which I know that it occurs at the Piesberg locality is M. scheuchzeri. The reconstruction of the frond for this species (Laveine and Belhis, 2007) is somewhat different (unfortunately, I do not have a digital copy of this paper). Now, I have the following questions: 1) How do you properly distinguish between M. macrophylla and M. scheuchzeri ? 2) Does this indeed look like the basal part of a Macroneuropteris frond ? Scale bar = 4 cm. Searching for green in the dark grey. Link to comment Share on other sites More sharing options...
paleoflor Posted April 25, 2015 Author Share Posted April 25, 2015 *bump* No takers? Anyone with an alternative identification? Searching for green in the dark grey. Link to comment Share on other sites More sharing options...
fossilized6s Posted April 25, 2015 Share Posted April 25, 2015 (edited) M. scheuchzeri is famous for it's hair like fibers (though not always present). Maybe look into Reticulopteris Munsteri or Neuropteris anomala. Your find seems too fat and pointy for a Macroneuropteris. Being that short, i would expect to see the tip rounded off. But i am far from expert in these matters. Just trying to help. It's a neat find. Congrats. Here's a M. scheuchzeri i just found last Sunday. Unfortunately it's missing the tip. Otherwise it is a pretty perfect example. Edited April 25, 2015 by fossilized6s ~Charlie~ "There are those that look at things the way they are, and ask why.....i dream of things that never were, and ask why not?" ~RFK ->Get your Mosasaur print ->How to spot a fake Trilobite ->How to identify a CONCRETION from a DINOSAUR EGG Link to comment Share on other sites More sharing options...
Plantguy Posted April 25, 2015 Share Posted April 25, 2015 Hey Tim, nice specimen. havent been on ff much lately...I think I have something somewhere about the basal pinnules--let me look around. The first thing I thought when I saw your specimen was M. macrophylla.. Regards, Chris Link to comment Share on other sites More sharing options...
paleoflor Posted May 1, 2015 Author Share Posted May 1, 2015 M. scheuchzeri is famous for it's hair like fibers (though not always present). Maybe look into Reticulopteris Munsteri or Neuropteris anomala. Your find seems too fat and pointy for a Macroneuropteris. Being that short, i would expect to see the tip rounded off. But i am far from expert in these matters. Just trying to help. It's a neat find. Congrats. No hairs are visible, but this could very well be a preservation effect (many specimens of M. scheuchzeri do not show these). Reticulopteris münsterii can be ruled out, as the veins in this specimen do not anastomose (characteristic feature of Reticulopteris). I am not familiar with Neuropteris anomala and will look into that particular species. Why do you reckon my specimen is too pointy of Macroneuropteris? The "fatness" of the pinnules could perhaps be explained by their position on the frond (that was my argument above). Hey Tim, nice specimen. havent been on ff much lately...I think I have something somewhere about the basal pinnules--let me look around. The first thing I thought when I saw your specimen was M. macrophylla.. Regards, Chris Thanks for your reply, also by PM. I am currently travelling, leaving me little time at present, but will reply upon my return next week. Tim Searching for green in the dark grey. Link to comment Share on other sites More sharing options...
Stocksdale Posted May 4, 2015 Share Posted May 4, 2015 1) How do you properly distinguish between M. macrophylla and M. scheuchzeri ? I've asked this question as well and never got a very clear answer. One thing I've noticed is that some examples of scheuchzeri tend to be slightly more symmetrical. The examples of macrophylla tend to have one side of the base larger. However, that might simply be a factor of the leaf's position on the frond. 1 Somewhere, something incredible is waiting to be known.–Carl Sagan Link to comment Share on other sites More sharing options...
paleoflor Posted May 4, 2015 Author Share Posted May 4, 2015 I've asked this question as well and never got a very clear answer. One thing I've noticed is that some examples of scheuchzeri tend to be slightly more symmetrical. The examples of macrophylla tend to have one side of the base larger. However, that might simply be a factor of the leaf's position on the frond. Thanks! Searching for green in the dark grey. Link to comment Share on other sites More sharing options...
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