## 3 Results
### Revised Boundary for the Genus Solorina  
The genus _Solarina_ has traditionally been recognized by its large, rounded, impressed apothecia that are immersed in the upper surface and typically concave, without a thalline margin. These traits distinguish _Solarina_ from its sister groups, _Peltigera_ [PERSON] and _Sinuicella_ [PERSON]. [PERSON], [PERSON]. However, significant morphological and chemical variations exist among the species within this genus. Furthermore, molecular studies suggest that _Solarina_ is polyphyletic [2; 23], indicating that these traditional characteristics are inadequate for reliably distinguishing this genus. Our three-loci-based analysis confirms previous findings regarding the polyphyly of _Solarina_[2; 23], revealing the division of this genus into two distinct clades. Based on the phylogenetic analyses and morphological and chemical characters, we define these two clades as representing two genera. The clade with a bright orange lower surface, which includes the type species _S. crocea_, was designated as the revised _Solarina_. According to this re-circumscription, species within _Solarina_ are characterized by a bright orange lower \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multicolumn{1}{c}{**Host**} & \multicolumn{2}{c}{**Chlorophyta**} & \multicolumn{2}{c}{**Cyanobacteria**} \\ \hline
**Taxon** & **Voucher** & **Taxon** & \
\begin{tabular}{c} **GenBank No.** \\ **ITS** \\ \end{tabular} & **Taxon** &
\begin{tabular}{c} **GenBank No.** \\ **16S RNA** \\ \end{tabular} \\ \hline _Pseudosolarina bispora_ & 24-76716 & _Cocomyxa_ sp. & PV085834 & _Nostoc_ sp. & PV083155 \\ \hline _Pseudosolarina bispora_ & 20-67082 & _Cocomyxa_ sp. & PV085836 & _Nostoc_ sp. & PV083158 \\ \hline _Pseudosolarina hepatizon_ & 17-55094 & _Asterochloris_ sp. & PV085839 & _Nostoc_ sp. & PV083157 \\ \hline _Pseudosolarina spongisoa_ & 24-76095 & _Cocomyxa_ sp. & PV085835 & – & – \\ \hline _Pseudosolarina parmigera_ & 24-76096 & _Cocomyxa_ sp. & PV085837 & – & – \\ \hline _Pseudosolarina saccata_ & XY23-383 & _Cocomyxa_ sp. & PV085838 & – & – \\ \hline _Pseudosolarina simensis_ & 23-75761 & – & – & _Nostoc_ sp. & PV083160 \\ \hline _Pseudosolarina tenuior_ & 23-75283 & – & – & _Nostoc_ sp. & PV083159 \\ \hline _Solarina crocoides_ & 23-75450 & _Asterochloris_ sp. & PV085840 & _Nostoc_ sp. & PV083156 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: The photobionts sequenced from _Solarina_ and _Pseudosolarina_, with corresponding GenBank numbers. The horizontal line signifies that the information is not yet available. surface and the presence of distinctive secondary metabolites, including solorinic acid. These species have apothecia which are flat or convexly immersed in the upper surface of the thallus (or apothecia absent), spores with nipple-like ornamentations, photobiont layer containing both cyanobacteria _Nostoc_ and chlorophyte _Coccomyx_ or _Asterochloris_, secondary metabolites including solorinic acid, averantin, 6-O-methylaverantin, and gyrophoric acid. The combination of these secondary metabolites produces the characteristic orange lower vsurface. Within the second well-defined monophyletic clade, all species have white or brownish lower thallus surfaces. This clade was established as a new genus _Pseudosolarina_ to accommodate the species which were excluded from the revised definition of _Solarina_. The species within _Pseudosolarina_ all exhibit apothecia immersed in the upper surface and slightly to deeply concave; their spores are distinguished by having broad reticulating ridges and irregular lacunae ornamentations. The photobiont layer contains _Nostoc_ and _Asterochloris_ or solely _Coccomyx_, with _Nostoc_ confined to cephalodia. Most species in _Pseudosolarina_ lack secondary metabolites. This taxonomic revision provides new classification boundaries for the genus _Solarina_ and _Pseudosolarina_, based on morphological, phylogenetic, and chemical characteristics. There are four other species previously defined as _Solarina_, for which genetic material was unavailable.