Scleritomes of Early Cambrian halkieriids have many more palmate and cultrate than siculate sclerites. On the other hand, siculate sclerites of "A. superstes" are more abundant than either cultrate or palmate sclerites; in fact palmate sclerites are rare. Possibly some process after death removed many of the palmates and some of the cultrates, but it is more likely that in "A. superstes" the part of the scleritome, or "coat of mail", closest to the sea-bed was larger relative to the lateral and dorsal zones further up and towards the center. "A. superstes" sclerites are also about one-third the size of Early Cambrian halkieriid sclerites. Since the Georgina assemblage includes larger fossils and most Early Cambrian halkieriids are preserved by the same method, phosphatization, it is unlikely that preservational bias has produced an unrepresentative sample. Possible explanations for the small size of "A. superstes" sclerites include: the individual(s) represented in the Georgina assemblage were juveniles; their scleritomes were composed of many more sclerites than those of Early Cambrian halkieriids; or the species itself was relatively small.