Stimpson, 1858
Carapace as wide as long or longer than wide, surface slightly convex, granulated and may be areolate. Lateral rostral teeth prominent, antero-lateral teeth small. Female sternal grooves end apart between or behind base of first legs. Cheliped with an epipod, but no podobranch. Chelipeds and first two pairs of legs with petaloid meri; carpi and propodi may be crested. First two pairs of legs without podobranchs. Legs not knobbed; inner margins of dactyli of first two pairs armed with up to seven small spines. Last two pairs of legs reduced, third pair shortest. Abdomen of six free segments; no vestigial pleopods on male abdomen. Uropod plates well developed, visible externally, used in abdominal locking mechanism. (Türkay 1995; Davie 1996)
Type species: Petalomera granulata Stimpson, 1858, by original designation and monotypy.
Species included:
Petalomera acutidens Sakai, 1983
Petalomera granulata Stimpson, 1858
Petalomera pulchra Miers, 1884