**4. Conclusions**

On the basis of phylogenetic and genomic evidence, strain AAP5 belongs to the species *S. glacialis*. This organism contains genes for anoxygenic photosynthesis as well as xanthorhodopsin. Although phototrophy is common among Alphaproteobacteria, the common presence of two phototrophic systems in *Sphingomonas* represents a unique phenomenon, which deserves further attention.

**Author Contributions:** Conceptualization, M.K.; Data curation, J.T.; Formal analysis, K.K. and J.T.; Funding acquisition, M. K.; Investigation, K.K., Y.Z., D.K., V.S., Z.G., R.S., and M.K.; Supervision, Y.Z., and M.K.; Writing – original draft, K.K., D.K., and J.T. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** The complete genome sequence is deposited at NCBI GenBank under the accession numbers: CP037913 (chromosome) and CP037914-CP037916 (plasmids). The GenBank accesion number for the 16S rRNA sequence is MW410774.

**Acknowledgments:** KK was partially funded by the Czech Science Foundation project no. 18-14095Y, DK was supported by the European Regional Development Fund-Project No. CZ.02.1.01/0.0/0.0/15\_003/00004The authors thank Sonja Koppenhöfer for help with the motility assay, Kasia Piwosz for conducting the IR epifluorescence microscopy, and Alastair T. Gardiner for English proof-reading.

**Conflicts of Interest:** Authors declare no conflict of interests.
