The geographical distribution and ecological habitats of the Pleurotus eryngii complex in Israel are described from a study of 60 genotypes from 10 populations. Both MEA and PDA media were suitable for growth of all genotypes at all temperatures tested (4–37 °C). There was a high correlation between a coefficient of growth and the mean colony diameter growth rate. All genotypes reached the maximum growth at 27°. Growth rate at 30° was greater than at 19°. We found highly significant (P < 0.0001) variability among growth rates of Israeli genotypes, indicating ecogeographical differences among populations. The growth rate of 12 European genotypes from the Ukraine and Slovakia was higher than most of the Israeli genotypes when grown at 27° (non-stress conditions), but Israeli genotypes tolerated 37° (stress conditions) better, and recovered faster than European populations when returned to 27°. We conclude that Israeli genotypes are better adapted to hot and dry climates than European genotypes. Based on multiple regression analyses, strong correlations were found between relative humidity and rainfall parameters, but not temperature, of the locations from which Israeli isolates were collected, and their growth rates. This indicates that, paradoxically, relative humidity and rainfall have a stronger effect than temperature on the adaptability of this complex to different environments.