The position of Callavia in relation to other Olenellina has shifted repeatedly over time. Initially it was assigned to the Holmiinae by Pierre Hupé, and was later moved back and forth to the Callaviinae.[4] Lieberman, however, argues Callavia is a basal member of the Judomioidea.[2]
C. broegeri is known from the Lower Cambrian of Newfoundland (Brigus Formation, Branchian Series, Conception Bay), Nova Scotia (between Docters Brook and Malignant Brook, northernmost Antigonish Highlands), Canada, and Massachusetts, USA (Weymouth Formation, Pearl street, North Weymouth, Mill Cove, Norfolk County).
Ecology
C. broegeri occurs together with lampshellsSunnaginia imbricata and Eccentrotheca kanesia, and
the agnostidSerrodiscus bellimarginatus.[5][6]