This is the first-known example of a strongly regular graph with parameters $(216,40,4,8)$, arising from an imprimitive action of the group $\mathrm{PSU}(4,2)$, discovered by Crnković, Rukavina and Švob (2018). We introduce the name "Rijeka graph" for this graph in honour of their home city.
| Number of vertices: | $216$ |
| Diameter: | $2$ |
| Intersection array: | $\{40,35;1,8\}$ |
| Spectrum: | $40^1 4^{140} (-8)^{75}$ |
| Automorphism group: | $\mathrm{PSU}(4,2):2$ |
| Distance-transitive: | No |
| Primitive |