Arthroaspis
{{Short description|Extinct genus of arthropods}}
{{Speciesbox
| fossil_range = {{fossil range|Cambrian Series 2}}
| image = Arthroaspis.jpg
| image_caption =
| parent_authority = Stein, M., Budd, G.E., Peel, J.S. et al 2013
| display_parents = 3
| genus = Arthroaspis
| species = bergstroemi
| authority = Stein, M., Budd, G.E., Peel, J.S. et al 2013
}}
Arthroaspis is an extinct genus of arthropod known from the Cambrian aged Sirius Passet Lagerstatte in Greenland. It is relatively large in size for Cambrian arthropods, attaining a length of up to 215 mm. It is a common component of the Passet fauna, being located at multiple localities within the formation. It possessed 14 tergites. In the describing paper, it was recovered as a member of a non-monophyletic Artiopoda.{{Cite journal|last1=Stein|first1=Martin|last2=Budd|first2=Graham E|last3=Peel|first3=John S|last4=Harper|first4=David AT|date=2013|title=Arthroaspis n. gen., a common element of the Sirius Passet Lagerstätte (Cambrian, North Greenland), sheds light on trilobite ancestry|url= |journal=BMC Evolutionary Biology|language=en|volume=13|issue=1|pages=99|doi=10.1186/1471-2148-13-99|issn=1471-2148|pmc=3662621|pmid=23663519 |bibcode=2013BMCEE..13...99S |doi-access=free }} It has subsequently been considered a potential close relative of nektaspids.{{Cite journal |last1=Mayers |first1=Benjamin |last2=Aria |first2=Cédric |last3=Caron |first3=Jean‐Bernard |date=January 2019 |editor-last=Zhang |editor-first=Xi‐Guang |title=Three new naraoiid species from the Burgess Shale, with a morphometric and phylogenetic reinvestigation of Naraoiidae |url=https://onlinelibrary.wiley.com/doi/10.1111/pala.12383 |journal=Palaeontology |language=en |volume=62 |issue=1 |pages=19–50 |doi=10.1111/pala.12383 |bibcode=2019Palgy..62...19M |s2cid=135331371 |issn=0031-0239|url-access=subscription }} Another paper from 2025 which re-analyzed the Burgess Shale artiopod Helmetia expansa, found Arthroaspis to be a basal member of the Conciliterga, within the Trilobitomorpha.{{Cite journal |last=Losso |first=Sarah R. |last2=Caron |first2=Jean-Bernard |last3=Ortega-Hernández |first3=Javier |date=2025-04-04 |title=Helmetia expansa Walcott, 1918 revisited – new insights into the internal anatomy, moulting and phylogeny of Conciliterga |url=https://www.tandfonline.com/doi/full/10.1080/14772019.2025.2468195 |journal=Journal of Systematic Palaeontology |volume=23 |issue=1 |pages=2468195 |doi=10.1080/14772019.2025.2468195 |issn=1477-2019 |doi-access=free|url-access=subscription }}