Herpetological expedition to the central regions of Iran
- Dates: May 2021
- Location: isolated sandy massifs of the Iranian Highlands.
- Participants: R.A. Nazarov, researcher at the Zoological Museum of Moscow State University, herpetologist.
- Funding from: The Russian Foundation for Basic Research (RFBR) and the National Science Foundation of Iran (INSF).
In May 2021, despite the troublesome situation caused by the COVID-19 pandemia, the regular herpetological expedition to the central regions of Iran took place. Its main task was to study the psammobiont herpetofauna (exclusive inhabitants of sands) of isolated sand massifs of the Iranian Highlands. A group of scientists of the Zoological Museum of Moscow State University and the Zoological Institute of the Russian Academy of Sciences, including several students of the Biology Faculty of Moscow State University, together with the Iranian colleagues, examined the sand dunes of central Iran.
Formal results of the expedition were as follows. During this field work, 294 specimens of psammobiont lizards belonging to 16 species (four of which being presumably new for science) were caught and studied. Each specimen was weighed, its body and tail lengths were measured, and tissue samples (tail tips) were taken for the subsequent DNA analysis. Besides, high-resolution photographs of the lower surface of the lizards' paws were taken (about 2000 images in total).
The idea to study sand massifs did not arise by chance, as several endemic species of lizards have been revealed as a result of many years of the research work in this region. Having outlined the contours of the main sand massifs on the map, we saw a mosaic of isolated sandy "islands". Such isolation could plausibly explain the high level of endemism of specialized psammobiont communities in this region. We intended to evaluate the relation between the particular sandy areas and morphological and genetic divergence in different groups of reptiles inhabiting them.
It would seem that what could be more monotonous and boring than a desert—a sun-scorched land practically devoid of life? In fact, this is not the case: the life here is quite diverse. In the northwest of the Dasht-e Kavir desert, sand dunes have been formed on the edge of the great salt Namak Lake under the influence of wind, with their height reaching 100 m (points 1 and 2 on the map). Three endemic lizard species were discovered in this massif: Eremias kavirensis, Eremias andersoni, and Ophiomorus maranjabensis. We had no luck with the former species before, as we have seen only three of its specimens during all previous trips. This year, luck has turned to face us, and more than 15 individuals have been recorded and caught on the route. Tissue samples were collected from them for the DNA analysis, the lower surfaces of the paws were photographed, and it appeared even possible to snap the photos of fighting males of this unique lizard.
In the central regions of Iran, sands accumulate in intermountain basins to form both local dunes of but several tens of hectares and huge plains. Specialized psammobiont reptile species are found everywhere here. In 2017, we discovered a new species of gecko from the vicinity of the village of Mesr, living on the sands. This species was named Teratoscincus mesriensis after the name of the settlement closest to the place of its catching.
One of the most amazing places that we had a chance to visit during this expedition was the largest sand massif in Iran, Rig–e Yalan in the Lut Desert (Point 7, on the map). This place is considered one of the hottest on the planet: in summer, the daytime air temperature often exceeds 45 °C, and the maximum temperature of the ground surface, recorded from a satellite, was more than 71 °C! The annual precipitation does not reach 100 mm in some years, and the height of the dunes can exceed 400 m. It would seem impossible to survive in such harsh conditions in the absence of open sources of drinking water. Nevertheless, the life does exist here. It was in these places that one of the most beautiful and bright species of the toad-headed agamas was discovered, Phrynocephalus lutensis (family Agamidae) in 2015.
1. The route localities where our research was carried out.
2. A fight between two males of the Kavir racerunner (Eremias kavirensis), vicinities of the Fort Maranjab.
3. A large sandy massif on the intermountain plain near the village of Mesr (point 14 on the map).
4. Rig-e Yalan sandy massif.
5. Field camp; the morning air temperature used to rise up to 40 °C by 9 o'clock here.
6. Salt lakes in the Lut desert often serve as the last refuge for birds that have strayed from their migration path.
7. The ruby eyes of the Persian wonder gecko (Teratoscincus keyserlingii) glowing in the light of a lantern.
8. A working process: you can work comfortably inside a caravanserai in the light of lanterns and kerosene lamps, when there is a wind with sand outside.
9-10. The secret toad-head agama (Phrynocephalus mystaceus) is the largest member of the genus. This species is widely distributed from northwestern China to northeastern Iran. It is an obligate psammobiont inhabiting only sandy massifs throughout its range. The biggest mystery of this lizard is why it possesses the "pinnas".