Grasping Appendage of Anomalocaris from Guanshan Biota

Description: The discovery of the Chengjiang Biota by Hou Xian-guang in 1984 opened a window onto a remarkable array of life forms from what is termed the Cambrian Explosion. The diversity of soft-tissue fossils is astonishing: algae, medusiforms, sponges, priapulids, annelid-like worms, echinoderms, arthropods (including trilobites), hemichordates, chordates, and the first agnathan fish make up just a small fraction of the total. Numerous problematic forms are known as well, some of which may have represented failed attempts at diversity that did not persist to the present day.

This is the grasping arm of the “Terror Of The Cambrian”, Anomalocaris, and it comes from what has been termed the “Guanshan Fauna”, found in the Wulongqing Formation. The Guanshan Fauna shares many genera with the slightly older Chengjiang Biota, but differs at the species level. The members of this group of enigmatic creatures are known from Asia, Australia, Europe, and North America, and are thought by many to be closely allied with the Arthropoda, as position not held by all researchers. The spiniferous grasping appendages are strongly suggestive of its carnivorous habits; some trilobites from Utah bear evidence of bite marks that have been attributed to Anomalocaris. The genus derives its name from “anomalous shrimp” which was what the describer thought the appendage was.

Also see: Chengjiang Biota Fauna List Chengjiang Fossils