SEM images of Marphysa ibaiensis sp. nov. Holotype UMTAnn 2179 (B, C, E, F), paratype AM W.54052 (A, D, G) A pectinate chaetae, chaetiger 97 B pectinate chaetae, chaetiger 10 C pectinate chaetae, chaetiger 88 D pectinate chaetae, chaetiger 88 E–F pectinate chaetae, chaetiger 125 G serrations and projections on limbate chaetae, chaetiger 31. Numbers denoted by arrows indicate the type of pectinate chaetae; 1. Thin, narrow isodont; 3.Thin, narrow heterodont; 4, 5. Thick, wide isodont; 7. Thick, wide anodont. Scale bars: 5 µm (A–B, D); 10 µm (C, F–H); 20 µm (E).