Fig. 4From: The oldest described eurypterid: a giant Middle Ordovician (Darriwilian) megalograptid from the Winneshiek Lagerstätte of Iowa Pentecopterus decorahensis, cuticular structures on prosomal ventral plate. a SUI 140009, lateral portion of prosomal ventral plate showing row of scales (arrowed) along the inner margin. b SUI 140009, prosomal ventral plate with terrace lines and ventral prosomal integument bearing setae. c SUI 140011, setae covering ventral prosomal integument. Each figure is oriented with the specimen anterior to the left. Scale bars = 1 mmBack to article page