Robuta

https://pmc.ncbi.nlm.nih.gov/articles/PMC4660871/ Armored kinorhynch-like scalidophoran animals from the early Cambrian - PMC Morphology-based phylogenetic analyses support the monophyly of the Scalidophora (Kinorhyncha, Loricifera, Priapulida) and Nematoida (Nematoda, Nematomorpha),... from thearmoredlikeanimalsearly