External surface (A–C) and skeletal structure (D–F) of the adhesive disc in members of <i>Acyrtus</i>.

<p>A, <i>Acyrtus lanthanum,</i> new species, ANSP 106336, 20.4 mm SL. B, <i>Acyrtus artius</i>, ANSP 94757, 24.2 mm SL. C, <i>Acyrtus rubiginosus</i>, UF 149202, 20.0 mm SL. D, <i>Acyrtus lanthanum,</i> new species, UF 212697, 18.0 mm SL; head of right pelvic-fin spine damaged. E, <i>Acyrtus artius</i>, ANSP 123658, 18.0 mm SL; anterior margin of left basipterygium damanged. F, <i>Acyrtus rubiginosus</i>, UF 149202, 20 mm SL. Letters A-C in A refer to disc regions as defined by Briggs (1955). Abbreviations in D: B, basipterygium; I, pelvic-fin spine; VP, ventral postcleithrum; 1–4, pelvic-fin rays 1–4. Scale bars equal to 500 µm (A–C) or 1 mm (D–F).