Throwing a bone to the invertebrate guys out there, here's new images of RMDRC 10-018 Spinaptychus sp. that yours truly found earlier this spring in Gove Co., Kansas. Ammonite remains are fairly rare in the chalk since the aragonitic shells do not readily preserve. These jaw parts however are calcitic in nature, and are occasionally found. We lent this specimen to Neal Larson of Black Hills Institute for detailed preparation and a bit of restoration before molding. He and his staff did an absolutely phenomenal job. Thanks again, neal!
The specimen is fairly large at over 5 inches wide, 4 inches long. The next project is determining what ammonite this specimen belongs to. Hopefully a paper will be coming out soon!