HOFMANN ET AL., 2008
The structure of Primocandelabrum sp. is very similar to P. hiemalorum, but it is slightly wider and apparently lacks the characteristic Hiemalora disc. However, this lack of disc has been suggested to be taphonomic (an artefact of how the fossil was preserved), and so Primocandelabrum sp. could be synonymous with P. hiemalorum rather than a separate species.
Narbonne et al. 2005 (field guide)
Hofmann, O'Brien and King 2008
Liu, Mcilroy, Antcliffe and Brasier, 2011
Wilby Carney and Howe, 2011