## 3 Results and Discussion
### Diversity of the Culturable Fungi  
The culture-dependent approach provided a good taxonomic resolution, resulting in a total of 135 isolates. Pure cultures were classified according to the observed characteristics of the colonies, and the representative fungal isolates were identified through amplification and sequencing of the ITS region of the rDNA. The morphological and molecular analyses led to the identification of 36 different species, together with 13 isolates for which a consensus on their identification was not attained (Table S1). Additionally, a few cultures of a filamentous actinobacteria of the genera _Streptomyces_ were also isolated but not considered in the further analysis. Diversity indices are presented in Table 2.  
Sample L3 revealed the highest species richness and Shannon index in contrast with sample L4 that presented the lowest. In turn, evenness was higher in L1, which indicates that the number of retrieved isolates from each species was more even in this sample. These are considerably different results from those obtained through metabarcoding. Most of the isolated fungi belongs to phylum Ascomycota (>90%), with phylum Basidiomycota being detected only in sample L3, with 2 identified species, representing 5% of the total abundance for that sample. Figure 7 displays the overall abundance results at the family (Figure 8a) and species levels (Figure 8b). \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Sample ID** & **Species Richness (S)** & **Shannon (H)** & **Evenness (e’H/S)** \\ \hline L1 & 14 & 2.63 & 0.99 \\ L2 & 15 & 2.35 & 0.70 \\ L3 & 18 & 2.68 & 0.81 \\ L4 & 6 & 1.53 & 0.77 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Diversity indices for cultivable fungal diversity. Figure 7: Depicting patterns of beta diversity for fungal communities in the different samples. (**a**) Principal coordinates analysis (PCoA) plot based on fungal genera composition. (**b**) UPGMA clustering analysis. The predominant families were _Aspergillus_ (33.3%), _Cladosporiaceae_ (25%) and _Hypocreaceae_ (16.7%) in sample L1; _Aspergillus_ (18.4% and 11.6%), _Cladosporiaceae_ (15.8% and 27.9%) and _Cordycipitaceae_ (39.5% and 20.9%) in samples L2 and L3, respectively; and _Aeminiaceae_ (14.3%), _Clandosporiaceae_ (21.4%), _Cordycipitaceae_ (57.1%) and _Aspergillus_ (7.1%) in sample L4. Overall, the most common families across all samples were _Clandosporiaceae_ and _Aspergillus_. In general, the most frequently retrieved isolates were _Acmonium alternatum_ (16.7%), _Aspergillus fumigatus_ (25%), _Cladosporium tenuissimum_ (12.5%) in sample L1; _Parengyodontium album_ (39.5%) and _Penicillium breicompactum_ (13.2%) in sample L2; and _Cladosporium spharoosperm_ (11.6% and 14.3%) and _Parengyodontium album_ (20.9% and 57.1%) in samples L3 and L4, respectively. Due to the low match similarity and unique morphological characteristics, 13 isolates were not able to be identified to the species or genus level, and will require further inves  
Figure 8: Relative abundance of the cultivable fungal diversity of all four sampling sites at (**a**) family level and (**b**) species level. tigation, as some may represent new taxa. The high degree of possible novelty and large variety of isolated fungi from a limited analyzed area of the rock surface point to a very rich and diverse pool of species in this habitat. Through the ecological co-occurrence network analyses, it can be observed that most of the isolated species are specific to a distinctive biodeterioration pattern. Ten species were retrieved exclusively from DGB, seven from GB, 13 from BD and two from SE. BD had the highest number of exclusive (13) as well of shared (eight) species. Only _Aspergillus fumigatus_ was present in all the biodeterioration scenarios (Figure 9).