India is one of the 12 mega diversity countries of the world due to high endemism. Rajasthan is the largest State of India and its major part is covered by the desert popularly known as the Thar desert. Anuran species are unique in this region but are facing problems due to extension of desert ranges, climate changes and habitat destruction. Out of the 225 species of anurans found in India, 12 species represented by four families namely Bufonidae ( Duttaphrynus melanostictus B. stomaticus, B. viridis), Ranidae (Euphlyctis cyanophlyctis E. hexadactylus Hoplobatrachus tigerinus F. limnocharis Sphaerotheca breviceps S. rolandae), Microhylidae (Microhyla ornata and Uperodon systoma) and Rhacophoridae (Polypedates maculates) have been reported by the author from Rajasthan. Very little attention has been paid for the identification of anurans on the basis of their calls from this region. Among these Bufonids and Microhylids are characterized by one vocal sacs, two in the Ranids but indistinct externally in the P. maculates. The spectrum generated using Raven Pro show very distinct call and pulse patterns in all these anurans. The highest Frequency ranges from 3.5 to 9.5 kHz in these species. In most cases dominant frequency is observed at low frequency ranges. In a call group, most Ranids show distinct inter call intervals but in the Bufonids such intervals are not distinct. Inter pulse interval is also very distinct in different species. The spectral pattern of these specie is so distinct that this can be used for identification, classification (sono-taxonomy) and monitoring of their population even in the desert habitats.
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