19	Ventromesial margins of ambulatory legs (pereopods 2, 3) armed with several irregular rows of numerous corneous spinules	20
–	Ventromesial margins of ambulatory legs (pereopods 2, 3) armed with single, regular row of corneous spinules	21
20	Propodal rasp of pereopod 4 with 2 or 3 rows of ovate scales; antennal flagella naked or with scattered short simple setae; fourth antennal segment armed with spine on dorsolateral distal angle; telson weakly asymmetrical	Paragiopagurus atkinsonae sp. n.
–	Propodal rasp of pereopod 4 with 1 row (at least distally) of ovate scales; antennal flagella densely covered with long mostly plumose setae; fourth antennal segment lacking spine on dorsolateral distal angle; telson strongly asymmetrical	P. ventilatus