Shell medium-sized for genus; color variegated dark brown and cream, cord interspaces with yellowish green metallic luster, particularly on base. Periostracum extremely thin, barely detectable. Protoconch dark brown, diameter 0.2 mm; teleoconch whorls 4,5 , suture distinct but not deeply impressed; aperture oblique, umbilicus deep, narrow; peritreme interrupted in parietal área, inner lip moderately thick, not reflected over umbilicus. Spiral sculpture of strong cords: rounded mid-whorl carination on first teleoconchwhorl, two cords of lesser prominence added on second whorl; penultimate whorl with three major cords and start of lesser, intercalary cords; cords on body whorl alternating in strength. Suture descending on final whorl to expose fourth major cord defining base. Axial sculpture lacking except for fine growth lines. Basal cords usually 7: two outermost cords strong, two middle cords narrower, and three near umbilicus strong and broad; this produces a shallow channel midway between basal angularity and umbilicus, producing also a slight indentation in basal lip. Umbilical wall smooth. Interior iridescent pink and green. Dimensions: Height 4.3 mm, diameter 4.3 mm (holotype).

This differs from L. succincta (Carpenter, 1864) in having stronger spiral cords, a more angulate base, and a color pattern of variegated brown and white, rather than uniform gray. Both species have the same kind of broad channel on the base, a feature shared by no other member of the genus. Lirularia optabilis (Carpenter, 1864) is a much larger species restricted to and common in the Pleistocene of southern California. Lirularia acuticostata (Carpenter, 1864) differs in having regular, sharp axial lamellae. Lirularia succincta, the species most closely related to L. discors, occurs from Cook Inlet, Alaska, to Piedras Blancas Point, San Luis Obispo County, California. Both species are sympatric in central California between the Farallon Islands and San Luis Obispo County. Here the habitat is partitioned: L. succincta is abundant in the intertidal zone and L. discors occurs in the shallow sublittoral zone, as shallow as 2 m. South of the range of L. succincta, L. discors is sublittoral, and, in areas of cool upwelling (as at the type locality), it is also intertidal. The name is a Latin adjective, meaning "different."

Type locality; 4-7 m on rocky bottom, south side of Punta Banda (near the blowhole), Baja California Norte, México (31°43.6'N; 116°43.0'W).