Search the Community

I managed a five hour solo hunt today prior to what will be a 12+ hour dig tomorrow. Being surrounded by frustrating Devonian material, I sometimes forget how exciting the Ordovician can be! But, as they say, "pictures or it didn't happen." First up, a weathered and bleached Ceraurus.

It's been awhile since I've made a post, I've been super busy in my junior year now and have been working quite a lot on my fossil project that will become my senior thesis! Anyway, today while examining my sphaerexochus specimens, I came across one which looks very different from the rest. From my research thus far it appears to be a Pseudosphaerexochus of some sort. What do you guys think? PART 1: Pseudosphaerexochus? Dorsal view of specimen Rotated Side view, Notice the prominent S2 furrow. None of my sphaerexochus specimens have this Pseudosphaerexochus? specimen (left) vs. one of my larger Sphaerexochus romingeri specimens. PART 2- Unidentified cheirurid pygidia In the process of counting and recording all the Silurian specimens for this project, I came across two pygidia I could not initially identify. I went to my guide to the fossils of Indiana reference book and found a picture that looks identical to the specimens in question. The book says they are Cheirurus niagarensis pygidia, so of course I was satisfied with this ID since I happen to have about a dozen C. niagarensis cephalons in my collection. However, upon further research, I have found that the pygidia specimens I have collected as well as the one mentioned in my reference book more closely resemble Sphaerexochus pygidia. Here are two pics showing both of my specimens. Here is the top specimen from the above pictures with the contrast enhanced Here is the picture from my reference book that is identified as a Cheirurus niagarensis pygidium And here is just one of many pictures I have found showing Sphaerexochus pygidia that resemble both my specimens and the one from my reference book Both Cheirurus and Sphaerexochus belong to the family Cheiruridae, so it makes sense that they might have very similar looking pygidia. However, I have yet to find any pictures (online or in text) that show a cheirurus pygidium that looks similar to the ones I have found. Perhaps my reference book has an incorrect identification or I just haven't done enough research yet!