Hallucigenia from Utah
Onychophora, Family Hallucigeniidae (Conway Morris, 1977)
Time: Upper Middle Cambrian
mm by 25 mm
Spence Shale, Box Elder County, Utah
is a fine though partial specimen of Hallucigenia, one of the most
usual fossils made famous by research of the Burgess
Shale. The genus is far better known from the actual Bugess
Shale of Canada, but a very few specimens have also been found in
Utah and the older Chengjiang
Biota. Hallucigenia was named by Simon Conway Morris when he
re-examined Charles Walcott's Burgess Shale genus Canadia in 1979.
This fossil comprises anteriormost portion of the animal, with several
of the paired spines (a complete specimen has seven pairs) and the
hint of the head. This is a most rare example of the early life
forms from the Cambrian
Explosion of Utah, which many people do not even know exists.
workers have compared the genus with another putative hallucigenid,
from the lower Cambrian Maotianshan shales of China, suggesting
placement in Phylum Onychophora. There are other interpretations
of the affinity of this long-enigmatic animal, such as that Hallucigenia
is an armored Lobopodian.
See: Utah Cambrian Explosion