The
ichnotaxon Platykopus (sometimes spelt
Platycopus) has sometimes been ascribed to Agriotheriini; a large ursid trackway assigned to
Platykopus stuartjohnsoni from late Miocene Texas was tentatively assigned to
Huracan coffeyi, due to
H. coffeyi remains being present at the same formation (Coffee Ranch Quarry), and their similarity to
Agriotherium africanum footbones from
South Africa. The type species
Platykopus ilycalcator was first recovered from late Miocene
Nevada, and has also been described from the Oligocene & Miocene of
Iran.
Platykopus maxima has been recovered from
Hungary, however researchers believe these trackways are of
amphicyonid origin due to their early Miocene age. Though both ichnotaxon are large-sized plantigrade footprints with five digits,
Platykopus is distinct from the ichnotaxon
Ursichnus (ursine and tremarctine bears). The oval digit imprints are usually connected to the palm/sole and close to the pad, sometimes with double lobed
phalangian pads instead of one. with subsequent digits forming a symmetrical arc around the palm/sole. The metatarsal imprint is underdeveloped in the palm, making the foot longer and narrower. Unlike other ursids, the manus and foot proportions and pads of
Platykopus are nearly 1:1; the tracks are smaller than other ursids (maximum foot length of 25cm), with a maximum foot length of 13.5cm. Absent in
Platykopus are primitive hallux imprints behind manus tracks, with claw imprints are only being slightly visible, similar to brown bear tracks. ==References==