A closeup of the aboral side of the central disk. Note that the radial shields (paired large central disk plates at the base of each arm) are longer than wide, and that their proximal ends are separated by a wedge-shaped group of scales while their distal ends are separated by an extension of an arm plate.
The arms of this species extend from slots in the central disk, as seen here. The plates at the edge of the slot are lined an "arm comb" of bristles which touch the edges of the arm. In this species the bristles of the arm comb are unusually flat and squared off, and the edge of each bristle is in contact with the edge of the next bristle so it is hard to see that the arm comb is distinct from the rest of the plate. In this photo the outline of several of the bristles of the comb can be seen along the edge of the upper plate. Note also that the aboral arm plates are wedge-shaped with the widest portion of each plate distal to the central disk.
This view of the underside of the central disk shows the white coloration on the underside. Also note that the oral shields (large plates seen between the bases of the arms) are widest near the middle rather than near the outer edges.
