Figure 4 in Phylogeny of the deep-sea cirripede family Scalpellidae (Crustacea, Thoracica) based on shell capitular plate morphology

Figure 4. Comparative morphology of out-group and basal scalpellid. A, B, Cretiscalpellum aptiensis Withers, 1935, capitulum, in lateral and carinal aspects. Bargate Stone, upper Aptian, Shackleford, Surrey, UK. Holotype, BGS 49533 (original of Withers, 1935, pl. 13, fig. 1). C–L, Cretiscalpellum striatum (Darwin, 1851b): C, carina (NHMUK IC 1191); D, F, rostrum NHMUK IC 1192); E, subcarina (NHMUK IC 1193); G, scutum NHMUK IC 1194); H, tergum (NHMUK IC 1195); I, carinolatus (NHMUK IC 1196); J, subcarinolatus (NHMUK IC 1197); K, inframedian latus (NHMUK IC 1199); L, upper latus (NHMUK IC 1200). Upper Campanian, Upper Chalk, Keswick, Norwich, UK. M–S, Arcuatoscalpellum arcuatum (Darwin, 1851b). M, exterior of rostrolatus (NHMUK IC 1221). N, exterior of scutum (NHMUK IC 12222). O, P, carinolatus (original of Collins, 1974, pl. 11, fig. 10, NHMUK In. 61368). Q, tergum (original of Collins, 1965, pl. 90, fig. 12, NHMUK In. 64259). R, S, carina in carinal and lateral aspect (NHMUK In. 1754). M, N, Upper Albian, Gault Clay. M, cristatum subzone (Bed 8i), Folkestone, Kent. O–Q, orbignyi subzone, Paddlesworth, Kent. R, S, Dunton Green, Kent. Note similarities in sculpture and overall valve morphology; the taxa differ importantly in the presence of a subcarina and subcarinolatus in Cretiscalpellum; these are absent from Arcuatoscalpellum gen. nov. Scale bars: A–B, 10 mm; N, Q, 5 mm; R, S, 2 mm; C, G, H, O, P, 1 mm; D–F, I–M, 0.5 mm.