The file MALDITOF_Similarity.xlsx contains a similarity matrix of all isolates and was created with the MALDI BIOTYPER 3.0 software (Component Correlation Index). The relationship between isolates is reflected by an arbitrary similarity level, with similarities normalized to a maximum value of 1. In this file, isolates are named only by their numbers, e.g. "Nr. 12" corresponds to isolate EK12. The following isolates were removed for all further analyses: 24, 25 (no partial LSU rDNA PCR products could be obtained) and 41, 42, 43, 44, 45 and 46 (obtained from plates incubated at 18°C, while all other isolates were obtained at 7°C). The reference spectra, which can only be assessed with the MALDI BIOTYPER software (Version 3.1.66), are available on request.