Figure 1.A Sternaspis sp. ventral view with some morphological features B Ventro-caudal shields of some Sternaspis species C Shield parts as herein proposed to distinguish different species (AD: anterior depression, FPP: fan posterior projection) (A modif. after Uschakov 1955, reproduced with permission; B–C modified after von Marenzeller 1890).
Figure 2.Variation of the ventro-caudal shield in Sternaspis affinis Stimpson, 1864, station 996 A Four specimens showing size differences B Specimen 1, ventro-caudal shield C Specimen 3, ventro-caudal shield D Specimen 4, ventro-caudal shield E Specimen 2, ventro-caudal shield F Same, ventro-caudal shield showing integument papillae. Bars: A 2 mm, B–F 1 mm.
Figure 5.Sternaspis affinis Stimpson, 1864, neotype (RBCM 005-138-001) A Dorsal view B Ventral view C Anterior end, frontal view (insert: juvenile, prostomium with eyes) D Ventro-caudal shield, frontal view E Posterior region, lateral view. Bars: A 1 mm B 1.1 mm C 0.8 mm D 0.6 mm E 0.7 mm.
