Hi Sergei, this one is very small and the lateral spines on pronotum are not very developped! So the antennae segments ratio (scape>3+4) and antennal lenght let me think to a small male of R. suturalis maybe var blumei.
It can be noticed that the taxonomic positioning of R. blumei is still confused since it was put in synonymy with suturalis by Lansberge,1884 (grouping collecting areas at the same time). No author or main database has revalidated blumei as good species. However, i'm still convinced that blumei could be considered as good species. R.blumei collected in Java/Sumatra is very different from suturalis (Sabah-Borneo) with a great elytral coloration variability and a different shape of pronotum. The only common character of the two species is the ratio of antenal segments and the same antenal lenght (certainly used by Lansberge for the synonymy argumentation).