1–2 Frontoclypeal area Cardiophorus Scale bar = 0.5 mm). 1 C. convexus (Say), (anteroventral view) 2 C. gramineus, (dorsal view). CE = compound eye; SC = supra-antennal carina; SG = supra-orbital groove. Figures captions include post-revision names 3–4 Latero-ventral view of hypomeron Scale bar = 1 mm) 3 Cardiophorus gagates Erichson 4 Paracardiophorus propinquus Lanchester. Ant = anterior; LC = lateral carina 5 Lateral view of prosternal process of Cardiophorus erythropus Erichson Scale bar = 0.5 mm). A length from procoxa to dorsal apex; Ant = Anterior B length from procoxa to end at halfway between dorsal and ventral apices C length from procoxa to ventral apex D vertical distance between dorsal and ventral apices. Dorsal and ventral apices are considered points where profile of respective surface is 45º from horizontal 6–9 Dorsal view of scutellum of Cardiophorinae Scale bar = 0.5 mm) 6 Esthesopus castaneus 7 Blaiseus bedeli 8 Cardiophorus gramineus 9 Floridelater americanus 10 Latero-ventral view of mesepimeron and mesepisternum of Cardiophorus fenestratus (LeConte) showing measurement of angle (a) of anterolateral corner of mesepisternum Scale bar = 0.5 mm). MST = mesepisternum; MRN = mesepimeron 11–13 Ventral view of left side of mesocoxal cavity of Elateridae (After Arnett 1960, scale bar = 1 mm) 11Elaterinae sp. 12 Hypnoidus sp. 13Cardiophorinae sp. Lat = lateral; MCX = mesocoxae MRN = mesepimeron; MST = mesepisternum; MS = mesosternum. Captions reflect the revised classification.