Phillipsia peroccidens - Second cranidium / glabella

If you read the description in the paper I sent you, Brezinski 2017 states the cranidium of Phillipsia peroccidens does not have tubercles.  This trilobite and the other cranidium / pygidium you posted, actually matches better with Piltonia carlakertisae, which Brezinski also mentioned in the paper and previously described as a new species (formerly Phillipsia tuberculata) from New Mexico in Brezinski 2000.  I would recommend contacting David Brezinski with this important new discovery and possible first record of Piltonia carlakertisae from the Redwall LS.  Attached for comparison is a complete example of Piltonia carlakertisae.

Brezinski, D.K. (2000)

Lower Mississippian trilobites from southern New Mexico.

Journal of Paleontology, 74(6):1043-1064  PDF LINK

Brezinski, D.K. (2017)
Trilobites from the Redwall Limestone (Mississippian) of Arizona.
Annals of Carnegie Museum, 84(2):165-171