Description: The Bear Gulch Limestone is a deposit of some 70 square km in extent and 30 m in depth that has been a source of one of the most diverse assemblages of fossil fish with some 110 species having been described over the past 30 years. Most were new to science, and provided a unique view of the marine environment of Mississippian times. Fine preservation of both fish and invertebrates is a hallmark of these deposits, presumably due to an anoxic depositional environment. Like the deposits of Mazon Creek, and extensive variety of worms are preserved at Bear Gulch. This specimen is a wormlike animal known as Deuteronectanebos. While the papillated and striated surface of this taxon is striking, it has yet to be placed in a known phylum. Some propose affinity with the Annelida, but that is not universally accepted.

Reference: Trans. San Diego Soc Nat Hist, Vol 10. No 9 8 Nov 1979 pp 107-120.