Arthropod

Marrella splendens

• Cambrian
• Burgess Shale, Stephen Formation
• British Columbia, Canada

Size: 1.5 cm

Though I focus mostly on crinoids and other echinoderms, certain fossils are worth having regardless of speciality. One of the best examples of such in my collection has to be this specimen of Marrella splendens from the historic Burgess Shale Lagerstätte of Canada, a site signficiant for advancing our understanding of multicellular life following the Cambrian Explosion. Marrella is the most common animal in the Burgess Shale and arguably the most iconic, and many similar forms found in other sites throughout the fossil record are referred to as "Marrellomorphs".

This unique stem arthropod had a headshield with four sweeping spines/horns, a pair of antennae, a pair of paddle-like anterior appendages, and a segmented body with a pair of appendages for each segment; all features seen on this lovely specimen. The animal was thought to be a benthic feeder and scavenger. Under certain angles of light the preservation takes on a bright silver sheen, which is classic for this locality. Also visible here and commonly seen for these fossils is a darkened stain around the posterior of the animal, which is thought to represent possible bodily fluids extruded during compression and fossilization.