Type species. Sphaerodorum sphaerulifer Moore, 1909.
Diagnosis. Body generally short and ovoid, some forms slender. Four or more longitudinal rows of macrotubercles, in one or several transversal rows per segment. Macrotubercles sessile and smooth, without terminal papillae. Microtubercles absent. Papillae over body surface and parapodia. Head appendages short, spherical or digitiform. Parapodia with compound chaetae; hooks absent.