Search the Community

I found this on a beach near Monterey Bay. (First image) At first I thought it was a rusted metal piece of something. But then I looked more closely, and I wonder whether it is a stigmaria, possibly from a lycophyte. The second image is a closeup of a portion of the first image. On the other side, I peeled away an overlying layer and exposed 5 more of the possible stigmara. (Third image) They appear somewhat hexagonal, though you may not be able to see it in the image. Finally, the fourth image is a closeup of one of the protrusions on the third image. There appears to be a pattern of tiny divots on it.

From my collection of St Clair plant material - any ideas? Less than half a centimeter thick, about two inches long.

Hello, this specimen is from the upper carboniferous (Westphalian) of southwest Poland. I bought it labeled "unknown plant". No doubt that it's from an arborescent lycophyte, but what part? One possibility is that it's the terminal end of a Stigmaria, and the rectangular "leaves" are appendages (rootlets). However, I miss the typical arrangement of the rootlet scars, and I didn't find pictures or reconstructions in the literature showing rootlets packed so densely around the apex. Note that the "leaves" are rectangular (and quite distant) relative to the main axis on the left and become parallel to the main axis and very densely packed near the end of the axis on the right. Here is a link to a reconstruction of the apex of a Stigmaria, and that looks different: http://www.google.de/imgres?q=Stigmaria&um=1&hl=de&sa=N&tbm=isch&tbnid=wv5blPXAFqF7CM:&imgrefurl=http://commons.wikimedia.org/wiki/File:PSM_V18_D633_Stigmaria_ficoides.jpg&docid=EUwsWaxbixUbWM&imgurl=http://upload.wikimedia.org/wikipedia/commons/7/7b/PSM_V18_D633_Stigmaria_ficoides.jpg&w=600&h=689&ei=yExzUJaMKs7Aswb5ioH4DA&zoom=1&iact=hc&vpx=642&vpy=10&dur=6484&hovh=241&hovw=209&tx=117&ty=124&sig=110097365356645860542&page=2&tbnh=152&tbnw=121&start=21&ndsp=28&ved=1t:429,r:19,s:21,i:202&biw=1246&bih=857 On the other hand, the grassy leaves remind me of vegetative leaves of Sigillariaceae (though I miss the doubled vascular strand that I would have to expect in that case). The length of the main axis is about 12 cm. Furthermore, there is an interesting small leaf (about 1 cm total length) near the left end of the matrix, above the main axis of the lycophyte. It looks ginkgo-like; but as far as I know, it looks too "modern" (and is too small) for the very early ginkgophytes that are known from the upper carboniferous. It looks more like mesozoic ginkgophyte leaves. Any suggestions? Thanks, araucaria1959