O'Keefe, F.R.; Chiappe, L.M.
taxonomy · range · morphology · ecology · geochronology
Adult and fetal material share catalogue number LACM 129639; viviparity is specimen evidence, whereas K-selection and social implications are comparative interpretations.
Adult Polycotylus specimen LACM 129639 contains a large articulated conspecific fetus and therefore supports viviparity; maternal care, sociality and a K-selected life history are not directly preserved behaviours.
claim:event:polycotylus-gravid-specimenPolycotylus is represented by gravid specimen LACM 129639 from the Late Cretaceous Pierre Shale at approximately 78 Ma; it is a local specimen boundary, not a genus-wide first or last appearance.
claim:taxon:polycotylus