Surname Riuka (Riuka 
) , around the world, is a very rare cognomen. The cognomen Riuka is characteristic of Lithuania, where it is quite a rare surname, Malaysia, where it is an extremely rare surname, and Nigeria. Likewise, Riuka is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Riuka | Nigeria, United States, Lithuania, India, Romania |