Named By: Charles Doolittle Walcott - 1911.
Classification: Animalia, Lophotrochozoa, Annelida, Polychaeta.
Species: C. spinosa.
Size: Between 5 - 20 centimetres long.
Known locations: Canada, British Columbia - Brugess Shale.
Time period: Delamaran of the Cambrian.
Fossil representation: Many individual specimens.
is probably known best today because another and very strange Cambrian
creature called Hallucigenia
was once included within the Canadia genus
until it was recognised to being different and separated in 1977.
Classification of Canadia has in the past been problematic because many of the creatures it was often associated with have since had their clasifications changed. The only confirmed location for Canadia is within the Polychaeta, as evidenced by the presence of parapodium, paired unjointed growths from the side of its body. Further refinement of this position cannot be agreed upon however because it is still uncertain how Canadia relates to modern annelids.
Canadia had the overall appearance of a polycheate worm, as you might expect from its classification. As such, Canadia had notosetae (rigid setae or ‘bristles’) that rose up from the back. These notosetae have the presence of what appear to be diffraction gratings present that would suggest that they were iridescent in life. These notosetae would have also been the main form of propulsion, allowing Canadia to swim through the water. However, Canadia probably searched for food on the seafloor with the small tentacles that extended from the prostomium (first body segment) seemingly serving as sensory devices.
Canadia is often classed as a detritivore, a bottom feeder that processes organic matter from the sediment, similar to an earthworm in your garden. However Canadia is thought to have potentially been carnivorous because the gut was straight with the presumed ability to extend out in a proboscis, a feature that is seen in some polychaete worms. The gut also displays a lack of sediment, something that should have filled its gut if Canadia was just a detritivore. Canadia may yet turn out to be a predator of other soft bodied organisms.