Abstract In the 100 years since the last comprehensive faunistic treatment of California beetles, there have been many advances in knowledge of the region's Coleoptera diversity. The intervening years' published literature was scoured for additions at both species and higher taxonomic levels. Reviewed here are four families and 25 subfamilies that have been added to the fauna during this period. The state's species list has grown from 3,404 species in 1901 to over 7,300 today. These data establish a baseline for an incipient inventory of the region.