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The present study is the first review of the recent herpetofauna of the Greater Caucasian caves. Also, it is worth noting some phossylous material on amphibians and reptiles (mainly Pleistocene remains) from the caves in this area. The goal of the study is to fill knowledge gaps and to present long-term data on the cave herpetofauna of the Greater Caucasus. In 1992–2019, amphibians and reptiles were found in 61 Greater Caucasian caves located in an altitude range from 55 m a.s.l. to 1300 m a.s.l. in Russia, Abkhazia, and Georgia. A total of 272 specimens representing ten species have been found. The most frequently observed species were Rana macrocnemis (39.0% of all recorded specimens), Pelodytes caucasicus (17.3%), Bufo verrucosissimus (11.0%), Darevskia brauneri (8.8%), Hyla orientalis (8.1%). The total proportion of the remaining five species (Ommatotriton ophryticus, Hyla savignyi, Pelophylax ridibundus, Anguis colchica, and Darevskia derjugini) was 15.8%. As a rule, representatives of the herpetofauna in the Greater Caucasian caves are quite rare and only single or few individuals are usually found. Exceptions were Fyodorovskaya Cave (Black Sea Region near the city of Sochi), Akshasha Cave, Abshdza Cave and Marshania Verkhnyaya Cave (last three in Abkhazia) where 141 specimens of amphibians and reptiles were observed, i.e. more than half (51.8%) of the totally recorded specimens. They belong to eight species (80.0% of all species found). The caves of the Greater Caucasus foothills, where the vast majority of amphibians and reptiles were observed, are usually characterised by a rich faunal diversity of invertebrate animals – their potential food. Amphibians were recorded from both twilight and deep parts of the caves, whereas lizards were found mainly close to the entrances, where the light penetrates and a relatively high air temperature is observed in the warm period of the year. Probably, some of the Greater Caucasian amphibians and reptiles enter the caves purposefully for wintering, and/or for feeding. The other animals occur accidentally in the caves (especially on the bottom of vertical pits), becoming «prisoners of circumstances». Judging by the length of time spent in the caves and, as a consequence, the change in body pigmentation (lighting of the main colouration tone) and good external condition of many individuals, these amphibians can be considered subtroglophiles. Rana macrocnemis, capable of laying eggs in caves, shows a tendency for eutroglophily. |
