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As I was working on some old 1080P video (replace with real still image) taken at the Oregon coast, I saw this little guy (either a chiton or isopod I believe) and thought how easy it would be to think it was an eyeless Trilobite. Have you seen any imposters (image, ID)?

Chitons are the most primitive of all living mollusks. They belong to a class called Polyplacophora (bearer of many plates). There lineage extends as far back as the late Cambrian. There are over 430 described species in the fossil record. Almost all are only known from individual body plates or valves. The Mazon Creek deposit is one of the only sites in the world where complete examples have been collected. Modern chitons have changed little from Glaphurochiton concinnus. The basic chiton body plan consists of 8 valves made of Aragonite. The front plate is named the cephalic plate and the rear plate the anal. The plates have fine ornamentation which is a key feature in differentiating species. Modern chitons can roll into a ball when threatened. The muscular body is known as the girdle. This girdle is covered with tiny spicules that are sometimes preserved on Mazon specimens. Most modern chitons use this girdle to attach themselves to rocks. To feed, the animal has a radula that can have over a hundred rows of denticles. Each row consists of 17 each. Most modern chitons attach to rocks and feed on algae. Glaphurochiton was a mud dweller feeding on detritus. Like all chitons, Glaphurochiton is strictly marine and is only found in the Essex portion of the deposit. Glaphurochiton is rare but 2 concentrations of chitons have been found. The areas have been termed “chiton hills”. It has been noted that modern chitons have a homing ability to return to there same resting spots despite lacking eyes. This first example is the largest chiton that I am aware of that has ever been found in the Mazon Creek deposit. Not including the skirt, the animal measures 70 millimeters. The typical size is usually between 30-40 millimeters.

I found this grayish sedimentary rock on the shore in Dunedin Florida, USA. It has a white grooved oval imprint on it like some critter fossilized on it. Could it be a Chiton? (Ruler is in inches) Thanks All.

I'm not sure what that is. I think it's a chiton, possibly of the genus Acanthopleura. Found in the Cretaceous (Lower Greensand) of Atherfield Point, Isle of Wight, England.

I found similar as I posted recently, found in Queensland, Australian ( southeast bay area) All comments welcome

I found these in the latest Maastrichtian, uppermost New Egypt fm. of NJ. Both pieces were basically found together which leads me to believe they are somehow related. I have never found anything else like it although I could have easily missed other similar objects since they are small and somewhat nondescript. The preservation reminds me of invert steinkerns found in the same layer. I thought these might possibly be pieces of some larger invert, but I have no idea what. And they really do look like 2 discrete structures instead of pieces of something larger. The local ammonite/invert expert of the Atlantic Coastal Plain, Ralph Johnson, was stumped as well, but suggested that they might be rhyncholites. I can definitely see a little resemblance to rhyncholites, but I would like to hear any and all opinions. Eutrophoceras is fairly common in this formation so it would make sense that these might be from a nautiloid. But please share any ideas and opinions on these that you might have! http://www.youtube.com/watch?v=g4JZWcsHflY