Amiskwia

Amiskwia is a genus of large, soft-bodied invertebrate of unknown affinity known from fossils of the Middle Cambrian Lagerstätten both in the Burgess shale formation in British Columbia and the Maotianshan shales of Yunnan Province, China.

Very few specimens of this organism have been found, only eighteen of the Burgess shale species, A. sagittiformis, and a single specimen of the Maotianshan species, A. sinica — which may be a reflection of its genuine rarity, but is more likely to be due to taphonomic (preservational) or behavioural factors. The fossils reach 25 mm (1 in) in length. The head is rounded, tipped with two tentacles, and appears to contain a four-ganglion brain; the body flattens out and broadens in the trunk, which appears to have been fairly muscular. Where the trunk meets the head there is a small tubular opening, which can be interpreted as the mouth; the gut terminates where the trunk narrows and meets the tail, which is broad and paddle shaped. The body morphology suggests a free energetic swimmer, which may be consistent with the dearth of fossils (in other words, a free-swimming animal would be able to avoid being buried alive in a mudflow on a regular basis, compared to a benthic animal).