Xandarella, an Exceptionally Rare Chengjiang Arthropod
with Extensive Soft Tissue Preservation

Description: This unusual arthropod is known as Xandarella spectaculum. The species is known from very few examples, some of which show many exquisite details. 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 areknown as well, some of which may have represented failed attempts at diversity that did not persist to the present day.

X. spectaculum is quite trilobite-like in appearance, but differs in the lack of a calcified exoskeleton and different eye morphology. The taxon is unknown outside the Chengjiang Biota. This is a truly unusual specimen preserved in ventral fashion, one that few will ever be able to hold in a collection, whether private or that of a museum. The preservation is superb, with the central gut well displayed. Note too the preserved biramous limbs and the antenna, all features usually not found preserved in such spectacular fashion, rending this an example true to the name of the species.

Also see: Chengjiang Biota for Fauna List Chengjiang Fossils