NancyPiper Posted April 12, 2021 Share Posted April 12, 2021 I found this in a spoils area of a strip area. Someone said it's from a scale tree. Can anyone confirm this. I clear coated it, that's why it's shiny. 3 Link to comment Share on other sites More sharing options...
Thomas.Dodson Posted April 13, 2021 Share Posted April 13, 2021 Yes, this is from a Lycophyte (scale tree). It looks like a specimen of outer bark which would put it in the form genus Lepidodendron. 1 1 1 Link to comment Share on other sites More sharing options...
NancyPiper Posted April 13, 2021 Author Share Posted April 13, 2021 Thank you. I'm used to seeing ferns and whatnot around here, but I've never seen this. Not that I fossil hunt a lot, but maybe I will now. Thanks again! Link to comment Share on other sites More sharing options...
Plantguy Posted April 13, 2021 Share Posted April 13, 2021 Very Neat find! Agree its a lycopod but it looks to have a more hexagonal leaf scar so probably one of the Sigillarias... Regards, Chris 2 1 Link to comment Share on other sites More sharing options...
paleoflor Posted April 13, 2021 Share Posted April 13, 2021 Might be useful to compare your specimen to Sigillaria elegans and Sigillaria brardii. 2 Searching for green in the dark grey. Link to comment Share on other sites More sharing options...
Rockwood Posted April 13, 2021 Share Posted April 13, 2021 1 hour ago, paleoflor said: Might be useful to compare your specimen to Sigillaria elegans and Sigillaria brardii. Why do these, and some other examples I find of the same, seem to be arranged more spirally than the typical columnar look ? Link to comment Share on other sites More sharing options...
paleoflor Posted April 13, 2021 Share Posted April 13, 2021 4 hours ago, Rockwood said: Why do these, and some other examples I find of the same, seem to be arranged more spirally than the typical columnar look ? Certainly no expert here. Hopefully @ziepe can provide a better explanation; I merely recognized the species from prior experience. For what it's worth, this is how I try to separate the different forms. The formgenus Sigillaria (or Eusigillaria, as this approach excludes Subsigillaria) can be subdivided into two groups, where the "Rhytodolepis group" has strong vertical ribs and the "Favularia group" has a very wavy or honeycomb-like structure. Forms from the latter group may appear to have spirally arranged leaf scars, but note the following: In the figure below, the yellow lines denote symmetry with respect to the vascular bundle and parichnos scars. The red polygons show the outline of a single "cushion". Note this outline is asymmetric with respect to the yellow line in Lepidodendron, while it is symmetric in Sigillaria (the difference can be quite subtle, though). The blue lines delineate the row-like orientation in Sigillaria and the spiral-like orientation in Lepidodendron. The black dotted lines show the possible "spiral-like orientation" in Sigillaria from the Favularia group, but this doesn't fit with the symmetry of the red polygon. The photograph above has to be rotated about 90 degrees counter-clockwise, but then you can see symmetric "cushions". Admittedly, this is a highly simplified approach, which probably leaves plenty of room for error. For example, Lepidophloios can have a similar appearance, with (nearly-)symmetric leaf cushions. Difference there would be the orientation of the vascular bundle and parichnos scars, which are directed downward. Note there are many more lycophyte genera, with which I'm entirely unfamiliar. 5 Searching for green in the dark grey. Link to comment Share on other sites More sharing options...
Rockwood Posted April 13, 2021 Share Posted April 13, 2021 Looks those Sigs. really have their ducks in a row after all. Link to comment Share on other sites More sharing options...
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