Early Pleistocene bivalve Mya arenaria Linnaeus, 1758, from the ‘Kor en Bot’ expedition in the Eastern Scheldt estuary: a dinner course of the walrus Ontocetus emmonsi Leidy, 1859?

Of 66 well-preserved early Pleistocene fossil shells of Mya arenaria L., 1758, sampled during the annual ‘Kor en Bot’ expeditions in 2013 and 2019 in Flauwers Pit I (Eastern Scheldt Estuary, The Netherlands), 65 specimens showed unusual damage. Judging the nature of the damage they were possibly victims of a large predator, presumably Ontocetus emmonsi Leidy, 1859. O. emmonsi may have used his incisors and/or canines to crack the shells before sucking in the animal. M. arenaria and O. emmonsi were most probably part of the same fauna. The origin of their fossil remains is the early Pleistocene (Gelasian) marine Maassluis Formation.