Acosta Hospitaleche and Reguero (2020) report the discovery of two mandibular fragments collected during 2016 and 2017 in Seymour Island, Antarctica, and assign them as Pelagornithidae indet. Morpho-Type 1. However, based on the published pictures of both specimens, it is clear that only IAA-PV 175 can be tentatively assigned to Pelagornithidae, whereas IAA-PV 823 truly belongs to a bony fish. Although this reasignation does not invalidate the general content and conclusions of their publication, we consider this reply important in order to clarify the assignation of IAAPV 823 and bring attention to the implications of this new interpretation in regards to the fossil record of fishes in the Southern Hemisphere.