Aviadactyla vialovi Kordos in Kordos and Prakfalvi 1990

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 Aviadactyla vialovi Kordos in Kordos and Prakfalvi 1990

Fig. 2 C, D

Materials.

One footprint in the sampled specimen ( IFMI -681 , partim) .

Revised diagnosis.

Avian footprints of small to moderate size, having slender and flexible digits ( II to IV) with slender claws whose inclination is only slightly divergent from the digit axis. The digits lack interpad spaces. Interdigital span variable according to pace and substrate, ranging from about 80 ° to over 155 °. The interdigital angle between digits II and III is slightly less than between digits III and IV. Proximally the digits converge, with digit II sometimes in slight contact with digit III; but digit IV is always separate and neither webbing nor a metatarsal pad are present. The digits are of comparable length, with digit III slightly the longest. Trackway of moderate width; stride of moderate length (emended by Sarjeant and Reynolds 2001).

Description.

Specimen IFMI - 681 (Fig. 2 B , track b) includes one tridactyl imprint, preserved as convex hyporelief, and consists of slender unconnected three-digit imprints. Digit III is relatively longer and slenderer than the lateral digits. Tips of the digits are sharp and no digit pads are visible.

Discussion.

Tridactyl unconnected footprints usually left by digitigrade track makers. The substrate conditions such as moisture and plasticity of sediments affect the quality of footprint preservation. Ichnospecies of Aviadactyla , and some Avipeda ichnospecies of ( A. adunca , A. ipolyensis ), and Koreanaornis ( K. hamanensis K. dodsoni , K. lii ) traces do not join digits proximally. Aviadactyla vialovi shows more slender digit imprints than A. media and A. panini and the digit imprints are slightly joined proximally.

Figures

Figure 2. A, B. Ardeipeda egretta, trackway a 1 – a 3 and Gruipeda dominguensis (b), sampled specimen, IFMI - 680; C, D. Aviadactyla vialovi trackway b 1 and Gruipeda dominguensis, trackway a 1 – a 4; mcc – mud crack cast; nvs – non-vertebrate structures; sampled specimen, IFMI - 681.