Artiopoda - Redlichiida - Holmiidae
Parent taxon: Olenelloidea according to J. M. Adrain 2011
See also Ebbestad et al. 2003, Lieberman 1999, Palmer and Repina 1993 and Whittington et al. 1997
Sister taxa: Biceratopsidae, Laudoniidae, Olenellidae, Wanneriidae
Subtaxa: Andalusiana Callaviinae Cambropallas Elliptocephalus Esmeraldina Grandinasus Holmia Holmiella Holmiinae Iyouella Montezumaspis Palmettaspis Postfallotaspis
Ecology: fast-moving low-level epifaunal deposit feeder
Distribution:
• Cambrian of Canada (10: Northern Territories, Northwest Territories collections), Morocco (4), Norway (6), Poland (2), Sweden (2), United States (92: California, Nevada, Pennsylvania, Vermont)
• Waucoban of United States (1: Nevada)
Total: 117 collections including 166 occurrences