This species is distinguished from all other members of Arctoraja by the absence of a complete row of middorsal thorns and with the ridge of clasper poorly developed (vs. strongly developed). It is further distinguished from B. parmifera which occasionally lacks middorsal thorns by having a narrow interdorsal space 0.1-1.4% TL (vs. 1.0-3.9% TL), distal projection of the ventral marginal projects directly distally (vs. distolaterally), ventral terminal lanceolate (vs. tear-drop shaped), dorsal and ventral marginals extending farther distally to distal tip of dorsal terminal 3 (vs. extending to about a quarter the length of dorsal terminal 2); from B. panthera by its narrower interdorsal length (vs. 1.4-3.1% TL), anterior portion of body shorter and narrower (vs. longer and wider), tail shorter (vs. longer), single cranial fontanelle (vs. separate anterior and posterior fontanelles), ventral terminal lanceolate (vs. tear-drop shaped), dorsal and ventral marginals extending farther distally to distal tip of dorsal terminal 3 (vs. extending to about a quarter the length of dorsal terminal 2); from B. simoterus by having fewer vertebrae 118-127 (vs. 131), fewer precaudal vertebrae 31-38 (vs. 41), larger mouth size 8.3-11.6% TL (vs. 8.1-9.1% TL), neurocranium with 1 fontanelle (vs. 2), internal carotid foramina close together in a single pit (vs. widely separated), scapulocoracoid with 5 foramina, anterior- and posteriormost larger than 3 intermediates (vs. 3 foramina, more posterior each slightly smaller), and pelvic girdle with 2 obturator foramina close together (vs. widely spaced) (Ref. 89865).