Rare Beckwithia typa Aglaspid Fossil from Utah

Description: Presented is a rare Beckwithia typa from Utah. This is a postive-negative pair. Unfortunately, this specimen cannot be prepared using air abrasion. The preservation is in the form of a faint mineral trace, with no “skin”, a typical preservation of soft-bodied animals. Note the unusual pale bluish color of the specimen, a hallmark of Beckwithia specimens found at the Weeks quarry site.

These are arthropods known as Aglaspids (unranked as Aglaspida or Aglaspidida). Aglaspids resemble the modern-day horseshoe crabs, and contain as the most famous member the Beckwithia typa shown here, a monsterous creature reaching up to some 20 cm in overall length that is thought to have been a predator of trilobites. Beckwithia was named after Frank Beckwith, editor and publisher of the Millard County Chronicle of Delta, Utah in the early to middle 1900s, a man with a passion for trilobites. Aglaspids are thought by some scientists to have made the trackways named Protichnites.

Hesselbo S.P. (1989) The Aglaspidid Arthropod Beckwithia from the Cambrian of Utah and Wisconsin, Journal of Paleontology, 63(5) 636-642.