Monica Posted October 9, 2016 Share Posted October 9, 2016 Hello everyone! Yesterday afternoon I went out to my usual site (Etobicoke Creek, Georgian Bay Formation, Upper Ordovician) and I found a couple of items that I've not found before... Specimen #1: possible trilobite trace fossil (Have I FINALLY found something that is trilobite-related for certain?!) Specimen #2: possible coral - the diameter of the corallites (if that's what they are) ranges from 2-3 mm Thanks for looking! Monica PS - I actually went out with both of my kids yesterday. Viola (almost 6 years old) found her usual stuff - lost of rocks containing crinoid discs. It was the first time I took William (3 years old) with me, and he actually found a fossil all by himself - it's just a rock that once had either a small orthocone nautiloid or a piece of crinoid stem in it, but he's pretty proud of himself Link to comment Share on other sites More sharing options...
Cluros Posted October 9, 2016 Share Posted October 9, 2016 I have seen trilobite traces very similar to the ones you have posted. The second photo certainly looks like corals I have collected. The internal geometry is correct. Link to comment Share on other sites More sharing options...
Trickworm Posted October 9, 2016 Share Posted October 9, 2016 That is what is called a Rusophycus. Basically it's a trilobite burrow that was most likely made by Flexicalymene. A day without sunshine is like, you know, night. Link to comment Share on other sites More sharing options...
caldigger Posted October 9, 2016 Share Posted October 9, 2016 I have a trilo trace fossil very much like those. Rusophycus pudicum (trilobite burrow trace fossil) upper Ordovician Period Cincinnatian series Latonia Formation Kenton County, Kentucky Link to comment Share on other sites More sharing options...
tmaier Posted October 10, 2016 Share Posted October 10, 2016 Yeah, Rusophycus. And the cxoral is likely a Favosite species. They look like a honeycomb on end, and in the side view they have those segments to them, because they are tabulate corals. http://www.google.com/search?q=Favosite&btnG=Search&hl=en&gbv=1&tbm=isch And the thrird photo shows a small piece of bryozoa in the middle left. Link to comment Share on other sites More sharing options...
Monica Posted October 11, 2016 Author Share Posted October 11, 2016 Hi once again! Well, while I was really excited to discover that I had finally found something trilobite-related here in the Toronto area, my daughter was a little disappointed that she still lacks trilobite material in her budding fossil collection. Consequently, we went out for an hour today, trying to look for more traces of trilobites and I came across something that may be another Rusophycus but I'm far from certain. I took a quick picture of the specimen this evening, but if it's still too difficult to tell then I can always take a better picture in natural light tomorrow afternoon when I get home from work. The specimen that I'd like your thoughts on is the one on the left - it feels similar to the ones on the right (which are definitely Rusophycus) because it feels like there are two lobes that border a slight indentation down the middle, and it looks as though there is a little trail/path just below the possible trilobite burrow: So, what do you think - Rusophycus or just another suggestive rock? I look forward to your input... Thanks again!!! Monica Link to comment Share on other sites More sharing options...
tmaier Posted October 11, 2016 Share Posted October 11, 2016 The two on the right definately look like trilobite feeding traces to me. They have the classic "lips" shape to them, and the roughness where the legs were working the silt. The one on the left is more of a puzzle. I can't see any distinctive features to tie it to a known trace type. I think it is likely to be a fossil something, though. Link to comment Share on other sites More sharing options...
JUAN EMMANUEL Posted October 28, 2016 Share Posted October 28, 2016 Hi, I just saw this topic just now. For the coral, that is not a native of the Humber Member of the Georgian Bay formation. The Humber Member of the Georgian Bay formation begins itself from the Humber River covering the Mimico and Etobicoke Creeks along the way, and stretches to the lowest part of the Credit River in Mississauga. It is not until you hit the Streetsville Member on the Credit that one can start finding corals. The Humber Member is more known for having a rich pelycopod fauna and that coral you showed looks foreign. Link to comment Share on other sites More sharing options...
tmaier Posted October 28, 2016 Share Posted October 28, 2016 The coral looks very rounded, like it has tumbled for some distance. Link to comment Share on other sites More sharing options...
fifbrindacier Posted October 28, 2016 Share Posted October 28, 2016 Yes, it is very worn. "On ne voit bien que par le coeur, l'essentiel est invisible pour les yeux." (Antoine de Saint-Exupéry) "We only well see with the heart, the essential is invisible for the eyes." In memory of Doren Link to comment Share on other sites More sharing options...
Monica Posted October 30, 2016 Author Share Posted October 30, 2016 On 10/27/2016 at 10:16 PM, JUAN EMMANUEL said: Hi, I just saw this topic just now. For the coral, that is not a native of the Humber Member of the Georgian Bay formation. The Humber Member of the Georgian Bay formation begins itself from the Humber River covering the Mimico and Etobicoke Creeks along the way, and stretches to the lowest part of the Credit River in Mississauga. It is not until you hit the Streetsville Member on the Credit that one can start finding corals. The Humber Member is more known for having a rich pelycopod fauna and that coral you showed looks foreign. Hi Juan Emmanuel! Thanks for looking at my finds! I was just wondering - I found a solitary rugose coral along Etobicoke Creek last month - would that also be a "visitor", just like the worn coral posted in this thread? Thanks for your help! Monica Link to comment Share on other sites More sharing options...
Stingray Posted October 31, 2016 Share Posted October 31, 2016 Monica, Someone on here has a tag line "A fossil is always where its suppose to be", or something along those lines. Not to dismiss documentation on locality, different exposures of rock can be found outside of the where there suppose to be category if that makes sense. Just recently I have found a trilobite that did not really belong in Eastern NY, but I tried discussing it with the Dipleura and it just ignored me and stayed there. In short there are no definitive answers, I like the burrows by the way and keep hunting that elusive trilobite ya never know. Link to comment Share on other sites More sharing options...
tmaier Posted October 31, 2016 Share Posted October 31, 2016 Loose fossils, being washed around into other formations, are called "floats". Documenting where a fossil is found is very important, but it is equally important to document if it was found "in situ" (where it was created) or if it was found out of context as a float. Link to comment Share on other sites More sharing options...
doushantuo Posted October 31, 2016 Share Posted October 31, 2016 The trilobite ichnofossil looks a lot like Bilobites(or even Cruziana/Rusophycus) It's probably a fodichnium(feeding and/or scratching trace) and not a cubichnium(resting trace) Nice find.I like it egenhoff_biostratigraphic_4107.pdf Link to comment Share on other sites More sharing options...
tmaier Posted October 31, 2016 Share Posted October 31, 2016 "The trilobite ichnofossil looks a lot like Bilobites" That is a class of trilobites, but how can you tell if one of those made the trace? "(or even Cruziana/Rusophycus)" Both of those terms refer to the characteristics of the trace, and the Cruziana is a long trackway, while the Rusophycus is a dig hole that normally looks like a pair of lips. The ones shown here are of the lips type, so would be Rusophycus. Cruziana http://www.google.com/search?q=Cruziana&btnG=Search&hl=en&gbv=1&tbm=isch Rusophycus http://www.google.com/search?q=Rusophycus+&btnG=Search&hl=en&gbv=1&tbm=isch The Cruziana often look like tiny motorcycle tire tracks running across the rock. Link to comment Share on other sites More sharing options...
doushantuo Posted October 31, 2016 Share Posted October 31, 2016 i should have used inverted comma's on "bilobites". Bilobites is something of a nominum nudum.It used to be the brachiopod Dicoloesia. I think it has been used very infrequently(can think only of Lebesconte and Yin),and mostly informally,to indicate a measure of uncertainty between naming the ichnite Cruziana or Rusophycus). Seilacher(in Crimes and Harper,Trace Fossils,Seel House Press,1970) has made a great inventory of the breadth of the taxon Cruziana(more recently,Sadlok, on C.semiplicata). A lot of Cruziana are cast on turbidite sole beds,so preservation varies Cruziana has also been found in non-marine basins(e.g.Triassic of Greenland). Some echinoderms make bilobed traces as well,btw Link to comment Share on other sites More sharing options...
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