Figure 4 in A taxonomic revision of Bolbapium Boucomont, 1910 (Coleoptera: Scarabaeoidea: Geotrupidae)

Figure 4. (a). Pronotum with robust bituberculated structure, connected at base and separated at the apex, Bolbapium quadrispinosum (Luederwaldt, 1931); (b). head with tranverse carina without tubercles, Bolbapium limeirai Carvalho and Vaz-de-Mello, sp. nov.; (c). head with tranverse carina with tubercles, Bolbapium furtadoi Carvalho and Vaz-de-Mello, sp. nov.; (d). head with tubercle adjacent to each eye, with base wider than apex, Bolbapium boillyi Carvalho and Vaz-de-Mello, sp. nov.; (e). clypeal carina extending to the mid-frontal region and meeting in the central region, Bolbapium paralucidulum Ide and Martínez, 1993; (f). clypeal carina short, not reaching the midline region of the frons, Bolbapium lucidulum (Klug, 1843).