Chrisanthidium was proposed by Urban (1997) to include Anthidium bidentatum Friese, 1908 and two new species. The genus can be recognized by the following combination of characters: female with mandible fourtoothed; male with densely setose area on mesal surface of hind coxa, T 7 with two conical apical process, and S 4 with a triangular area covered by two layers of overlapping setae; S 4 and S 5 with lateral spine-like projections; juxtantennal carina absent, omaulus rounded and postspiracular fovea absent (Urban 1997). Chrisanthidium is known from Chile and Argentina, and specimens are rare in collections. C. adornatum and C. nigritum were originally described based only on females; the male of C. nigritum was later described by Urban (2001).