I don't agree with the title, but the fossil is cool, a renamed and reclassified horseshoe crab from Tasmania.
https://m.phys.org/news/2019-10-oddness-australian-creatures.html
This particular species had spines attached to the shell which is not all that common. There are four spines attached on the thumbnail brachiopod. The holes in the shells were where spines used to be attached. Found during this trip here: