L. Forró - É. Murai szerk.: Miscellanea Zoologica Hungarica 6. 1991 (Budapest, 1991)

Gubányi, A.; Pekli, J.: Contribution to the knowledge of green frog populations (Rana esculenta complex, Anura, Amphibia) of the Kis-Balaton Landscape Protection Area, Hungary

Table 3. Summary of variation in seven ratios of adult female and male water frogs collected from three sampling sites at the Kis-Balaton Landscape Protection Area. Upper line: arithmetic means and standard deviations; lower line: significance of the difference between males and females (Mann-Whitney U test). * = difference significant at 95 % confidence level. ** = difference significant at 99 % confidence level. Sample sizes are given in parentheses. Rana lessonae Rana esculenta Vörs Reservoir Diás island Reservoir Males(21) Females(18) Males(6) Females(8) Males(17) Females(24) Males(10) Females(47) LC/LT 2.2±0.1 2.2±0.1 2.2±0.0 2.2±0.2 2.2±0.0 2.2±0.ö 2.0±0.9. 2.1 ±0.1 0.099 0.572 0.016* 0.208 LC/LF 2.1 ±0.1 2.1 ±0.0 2.1 ±0.0 2.1 ±0.2 2.1±0.0 2.1±0.1 2.0±0.1 2.1 ±0.1 0.665 0.345 0.078 0.024* LC/DP 8.2±0.6 7.8±0.7 8.2±0.6 7.9±1.1 8.2±0.5 7.8±0.7 6.9±0.4 7.3±0.4 0.064 0.949 0.289 0.031* LC/CIL 14.2±0.8 14.9±1.6 14.2 ±0.9 15.0±1.4 13.6±1.1 14.9 ±1.6 16.6±1.3 16.9±1.5 0.245 0.282 0.483 0.651 LF/LT 1.0±0.0 1.0±0.0 1.0±0.0 1.1 ±0.0 1.1±0.0 1.0±0.1 1.0±0.1 1.0±0.0 0.727 0.345 0.172 0.023* LT/CIL 6.4 ±0.4 6.8 ±0.9 6.4±0.4 6.8±1.1 6.1 ±0.4 6.8±0.9 8.1 ±0.7 8.1 ±0.8 0.202 0.949 0.435 0.785 DP/CIL 1.7±0.1 1.9±0.3 1.7±0.1 1.9±0.4 1.6±0.1 1.9±0.3 2.4 ±0.3 2.3±0.2 0.073 0.949 0.791 0.275 LC/LT = Body length/Tibia; LC/LF = Body length/Femur; LC/DP = Body length/First toe length; LC/CIL - Body length/Inner m. t. length; LF/LT = Femur/Tibia; LT/CIL = Tibia/Inner m. t. length; DP/CIL = First toe length/Inner m. t. length. DISCUSSION The hybrid origin of Rana esculenta and its coexistence with one of the parental species or both of them make the identification of green frogs even more difficult. Because of morphological measurements and strict positive correlation among length measurements one generally applies morphometric ratios. The indices DP/CIL and LT/CIL have been used in the last three decades for morphological discrimination (see Introduction). The LC/CIL and the two ratios mentioned above didn't show sexual dimorphism in our samples from the Kis-Balaton Landscape Protection Area. This result was similar to BERGER's (1966) and BORKIN's (1979) investigations. The upper value of the standard deviation in DP/CIL and LT/CIL indices in R. lessonae agreed with the value of the identification keys suggested by ENGELMANN et al. (1985) for distinguishing between R. lessonae and R. esculenta. Thus 12.9 and 9.6 per cent of pool frog individuals were proved to be extremes. On the other hand 9.9 and 13.0 per cent of edible frogs had similar features. Morphological measurements of frogs captured in Kis-Balaton Reservoir (Table 2) showed larger values than the others. This may be attributed to the productivity of the biotope, prédation and cannibalism that occurred among R. esculenta individuals.