Zur Ökologie und Verbreitung der Froschlurche in den Himalaya-Durchbruchstälern von Zentral-Nepal (Kali Gandaki, Marsyandi) (Anura, Amphibia) Von Thomas Späth Späth, T. (1992): Zur Ökologie und Verbreitung der Froschlurche in den Hima-laya-Durchbruchstälern von Zentral-Nepal (Kali Gandaki, Marsyandi) (Anura, Amphibia). -Spixiana 15/3: 303-329. Data of the ecology and distribution of the 12 amphibian species were collected in the 2 transhimalayan gorges of the Marsyandi and Kali Gandaki rivers (Central Nepal) in order to study the effects of the extreme conditions and steep climatic gradients on the autochthonous amphibian fauna. A key for the identification of the amphibians of the area was made. According to their biogeographical derivation, their spawning-and adult-habitats and their distribution in the study area, the 12 spe-cies can be divided into three groups: the panoriental, pool spawning species of the open, man-made habitats of the tropical/subtropical zone; the east himalayan-indochinese, brook breeding species of the remaining forest-habitats in the subtropi-cal and humid-temperate regions; and the mainly waterbound, pool-and brook spawning, himalayan-tibetan species of the arid-temperate and subalpine areas. Both pond-and brookbreeders show some quite distinctive adaptations to their spawning habitats. The effects of the steep climatic and isolating topographical factors in the transhimalayan gorges on the anurans seemed to result in increased speciation, i. e. recently there are more closely related species than there is a high degree of intra-specific Variation as lt could be explained by climatic gradients: the 4 species of the subgenus Rana (Paa) and the 2 Bufo species in the study area might support this assumption. A comparison of the amphibian fauna of the 2 Valleys supports the hypothesis, that Poikilothermie animals can reach higher altitudes when the condi-tions are dry and sunny rather than wet and clou-dy. An unusual Situation show the Bufo melanostictus X Bufo himalayanus hybrids, which coexist in most of their distribution area only with one parental species. The total Situation reminds of a hybridogenetic reproduetion mode, which is known for anurans only from the european Rana "esculenta" complex. The human impact on the amphibians of the area studied is threefold: positive for the species of the man-made, open habitats of the tropical/subtropical zone; negative for the dense-vegetation-dwellers of the more natural habitats of the subtropical and humid-temperate regions; and more or less balanced for the species of the arid areas. Dipl.-Biol. Thomas Späth, Mattenweg 13, W-7811 St. Märgen 1. Einleitung Auf Grund der extremen Variation klimatischer Faktoren auf engstem Raum erschien der zentrale Nepal-Himalaya besonders günstig, um die evolutionsbiologisch und ökologisch interessante Frage 303
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