Moropopus kashanensis, Abbassi & Salehi Tinooni & Ghorbani Dehnavi & Shakeri & Eshaghi, 2024

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

Ichnospecies Moropopus kashanensis isp. nov.

Fig. 8

Materials.

Two footprints of one trackway, sampled ( IFMI -686 / 1-2) .

Holotype.

specimen IFMI -686 .

Etymology.

kashanensis refers to Kashan city where the traces were found.

Type-locality.

Iran, Esfahan (= Isfahan) province, Kashan township, west Ab Shirin, northwest Deh Nar, 34 ° 19 ' N, 51 ° 12 ' E.

Type horizon.

lower Oligocene (Rupelian).

Diagnosis.

Moropopus with tridactyl footprint in pes and manus imprints. Pes has elongated digit imprints; digit III is larger than the lateral digits II and IV. Tips of digits are completely round. The manus imprint has a digit III that is longer than the lateral digits. The tip of digit III is round, but lateral digits end with a distally sharp claw-like imprint.

Description.

The smaller posterior footprint is considered as a pes imprint and it includes two digit imprints and one of the lateral digit and most parts of the metapodial imprints are omitted by weathering. Digits include one pedal circular imprint with round tips, and connect by a narrower imprint to the metapodial imprint. The anterior larger imprint is the manus imprint and it is distinguished by the sharp tip of the lateral digit imprints and it seems that the middle digit imprint has a round tip. The metacarpal imprint is circular, with a round proximal outline.

Discussion.

The general morphology of Moropopus with elongated distally swollen digit imprints is traceable in these footprints, but the distinctive feature is the sharp tips of lateral digits. Usually, perissodactyls have round distal outlines in hooves, and there are no records of sharp tips. The skeletal remains of pes and manus of perissodactyls anatomically comprise distally round phalanges (ungula) with or without medial fissure and covered by fat digital pads or round unguals. Instead, the unguals of artiodactyls usually have sharp tips.

Moropopus kashanensis however shows strongly sharp tips in lateral digits of the manus imprint. No secondary deformations such as drag marks or combination with non-biogenic structures were included in the detailed analysis of the tips of Moropopus kashanensis . Thus, we believe these footprints are a new ichnospecies of Moropopus .

Figures

Figure 8. Moropopus kashanensis nov. in the studied slab (A); B – D. Holotype of pes imprint with outline sketch and photogrammetry photo (IFMI - 686 / 1); E – I. Holotype of manus imprint with its outline sketch (F) and photogrammetric false-color depth maps, (G, H) and closeup of digit claw imprint (I arrow), (IFMI - 686 / 2).