Moropopus Abbassi, Alinasiri & Lucas, 2017

Abbassi, Nasrollah, Salehi Tinooni, Mohammad, Ghorbani Dehnavi, Mahdi, Shakeri, Safoora & Eshaghi, Ali, 2024, Oligocene vertebrate footprints from the Lower Red Formation, Central Iran, Fossil Record 27 (2), pp. 265-287 : 265-287

Ichnogenus Moropopus Abbassi, Alinasiri & Lucas, 2017

Type ichnospecies.

Moropopus elongatus Abbassi, Alinasiri & Lucas, 2017 .

Emended diagnosis.

Medium-sized tridactyl footprints with elongated oval to ellipsoidal to fusiform digit imprints. Two digital pads may be present in lateral digits. Digit imprints connect to metatarsus by a narrower proximal imprint. Lateral digits (digit II and IV) are smaller than the middle digit (digit III) and are curved toward the front. Digit III imprint is wider in the front. Digit III tip is completely curved, and the tips of lateral digits may curve or end in elongate sharp tips, like the claw imprints. Metatarsus imprints include two metatarsal pads with a complete rounded back, or with two lobes.

Discussion.

The narrow proximal part of digit imprints is a distinctive feature of Moropopus , which distinguishes it from the other tridactyl ichnogenera of perissodactyls. The presence of sharp tips on the lateral digits of the pes imprint of the Deh Nar footprints caused an emended diagnosis of Moropopus and introduced a second ichnospecies of Moropopus .

In Asia, mammal tridactyl ungulate footprints have been reported from Early Tertiary of China (Lockley et al. 1999), Oligoene of India ( Rajkumar and Klein 2014) and Eocene-Oligocene of Iran ( Abbassi et al. 2015, 2017). Oligoene tridactyl footprints of India strongly resemble those described from China ( Rajkumar and Klein 2014) and differ from Iran’s Oligocene tridactyl footprints in morphology and size. Demathieu et al. (1984) reported Ronzotherichnus with short digit imprints not connected to the metatarsus imprint and thus differing from Moropopus . Usually, tridactyl footprints in perissodactyls show round outlines in the distal part of digits, however some ichnogenera of tridactyls have sharp tips in the lateral digits, such as Plagiolophustipus Santamaria et al. (1989–1990 ). Moropopus differs from Plagiolophustipus by its narrow digit III imprint.