Fig. 17From: The oldest described eurypterid: a giant Middle Ordovician (Darriwilian) megalograptid from the Winneshiek Lagerstätte of Iowa Pentecopterus decorahensis, genital appendage and operculum. a SUI 140003, genital appendage missing left lobe. b SUI 140008, incomplete genital operculum with left ala and deltoid plate. DP = deltoid plate, FO = follicles, SC = scales. Scale bars = 10 mmBack to article page