The Amphoracrinidae Bather, 1899 is redefined, and all genera of this family are diagnosed with objective characters. DilatocrinusWebster and Lane, 1987 and PimlicocrinusWright, 1943 are transferred into the Amphoracrinidae. Type specimens that define DisplodocrinusWebster and Lane, 1987 and DilatocrinusWebster and Lane, 1987 are clarified. The emphasis here is on genus definition, and comprehensive species-level systematics is not attempted. However, Amphoracrinus blairiMiller and Gurley, 1896a and Amphoracrinus jessieaeMiller and Gurley, 1896b are designated nomina dubia; Sampsonocrinus sp. Webster and Lane, 1987 is reassigned to Amphoracrinus rupinusWebster and Lane, 1987; Amphoracrinus divergens var. multiramosus (Meek and Worthen, 1866) is reassigned to Dilatocrinus multiramosus (Meek and Worthen, 1866); and Sunwaptacrinus nevadensisWebster and Lane, 1987 is reassigned to Displodocrinus nevadensis (Webster and Lane, 1987).

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