The First Complete Mitochondrial Genome of Lecanora argopholis and Its Phylogenetic Implications for Lichen-Forming Fungi

We report the first complete mitochondrial genome of the crustose lichen-forming fungus Lecanora argopholis. The circular mitogenome is 48,790 bp in length, has an overall AT content of 70.4%, and contains 14 protein-coding genes (PCGs), two rRNA genes, and 29 tRNA genes. Comparative analysis of four Lecanora species showed that mitochondrial tRNA features were generally conserved, although limited variation in tRNA length and predicted base-pairing patterns was observed among the sampled taxa. Relative synonymous codon usage analysis of 13 shared mitochondrial PCGs revealed a similar preference for A/U-ending codons across the four species, indicating that this pattern is not unique to L. argopholis. Expanded synteny analysis of eight lichen-forming fungal mitogenomes identified conserved homologous blocks together with variation in mitochondrial gene order; among the sampled taxa, L. argopholis and L. cinereofusca showed the highest gene-order conservation. Phylogenetic analysis based on 14 concatenated mitochondrial PCGs from 17 lichen-forming fungi recovered L. argopholis as sister to L. cinereofusca, providing additional mitochondrial evidence relevant to the placement of L. argopholis within the taxonomically complex Lecanora s. lat. These results expand the mitogenomic resources available for Lecanora and provide comparative information on mitochondrial genome organization and evolution in lichen-forming fungi.