A review of the distribution of diploid, triploid and tetraploid Green Toads (Bufo viridis complex) in Asia including new data from Pakistan

Abstract

A summary of the distribution of green toads containing most of the data published after the discovery of polyploid forms (1976) including a map, an index and a bibliography are presented and discussed. 21 Asian type localities of hitherto described nominal green toad taxa are shown. The tetraploids are distributed in high mountains and extremely continental regions with strong climatic shifts. Records of triploid specimens are situated in supposed contact zones between the parapatric diploid and tetraploid toads at foothills of Middle Asian high mountains, and triploid bisexual populations occur in the Karakoram and West-Himalayas. Habitats of diploids appear to be restricted to lowlands and valley grounds. Polyploids seem to be more resistant. The methods hitherto used for the determination of the ploidy level and their applicability are evaluated. We show new data on this species complex from Iran including cytometric, karyological, bioacoustic and morphological data and we draw taxonomic conclusions for tetraploid Bufo oblongus, diploid Bufo viridis kermanensis, and probably diploid Bufo kavirensis. New information on the distribution of triploids in northwestern Pakistan based on flow cytometric measurements is presented. The ploidy level of Bufo latastii is revealed to be diploid.