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Ventral cephalic structures of Arthroaspis bergstroemi n. gen. n. sp. A. MGUH 30417, showing impression of hypostome and cephalic sternites (dorsal aspect); B. MGUH 30391, showing the insertion of cephalic appendages (ventral aspect); C. MGUH 30407 (cpt), close up of anterior glabellar region, showing preglabellar crease and possible median node.
