Fig 18. Chthamalus panamensis specimens. A in Biodiversity and Biogeography of Chthamalid Barnacles from the North-Eastern Pacific (Crustacea Cirripedia)

Fig 18. Chthamalus panamensis specimens. A. from Avenida Amador, Naos Island, Panama, Panama, showing the top view of shell and the appearance of the longitudinal furrow (LF) on tergum, through the orifice. B, The intact specimen illustrated in Pilsbry's Plate 75, fig 2a is selected by the present authors as the Lectotype, showing the longitudinal furrow (LF) on the outer surface of the tergum. C-F, from Avenida Amador, Naos Island, Panama. SEMs of scutum and tergum from 4 specimens. Note the variation in the shape of the tergum among individuals. C, outer view of scutum and tergum, showing horizontal growth lines and longitudinal furrow on tergum (LF). D, scutum and tergum (inner and outer view) showing longitudinal furrow on tergum outer surface. E, F, inner side of scutum and tergum. doi:10.1371/journal.pone.0149556.g018