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Larval attachment organs (LAOs) are unicellular or multicellular organs that enable the larvae of many actinopterygian fishes to adhere to a substrate before yolk‐sac absorption and the free‐swimming stage. Bowfins (Amiiformes) exhibit a sizable LAO on the snout, which was first described in the late 19th and early 20th centuries. In this study, we document the LAO ofAmia ocellicauda(Richardson, 1836) using a combination of scanning electron microscopy (SEM) and light microscopy, and histochemistry. We examined material representing three stages with SEM ranging in size from 5.8 to 11.2 mm in notochord length and one stage histochemically. We compare the LAO ofA. ocellicaudato that of the lepisosteidAtractosteus tropicusGill, 1863 and show that although the LAOs ofA. ocellicaudaandA. tropicusare both super‐organs, the two differ in the ultrastructure of the entire organ.A. ocellicaudapossesses two distinct lobes, with the organs arranged on the periphery with none in the middle, whereasA. tropicusalso possesses two lobes, but with the organs scattered evenly across the super‐organ. The individual organs ofA. ocellicaudapossess adhesive cells set deep to support cells with the adhesive substance released through a pore, whereasA. tropicuspossesses both support cells and adhesive cells sitting at a similar level, with the adhesive substance released directly onto the surface of the organ. We additionally provide a table summarizing vertebrate genera in which attachment organs have been documented and discuss the implications of our study for hypotheses of the homology of attachment organs in the Holostei.