Phacops Trilobite with Most Unusual Color Preservation

Description: Notice the pleasing café au lait color, and the regular faint darkened spots to the exoskeleton. These marking have been interpreted as the positions of internal muscle attachments. An alternative hypothesis is that the dark spots are actually preserved melanophores which could expand an contract , allow the trilobite to change color as it moved about the seafloor surface much like the extant Plaice and Sole. Whatever the correct interpretation, these colors are of natural, rather than diagenic origin. The specimens were collected from a site on the border with Pennsylvania several decades ago, and to my knowledge specimens such as these have not been offered commercially until recently. This fine prone example is of a juvenile E. norwoodensis (sometimes E. rana norwoodensis), and is the first of this species with such color preservation I have offered.

Reference: Paleontology Vol. 11, Part 4, 1968 pp 498-9