And from among his brothers he took five men

It's interesting that the names of these five men are never mentioned. I wonder who they are? The account in Sefer Yashar says four of Joseph's brothers, who is the fifth?

https://www.sefaria.org/Sefer_HaYashar_(midrash)%2C_Book_of_Genesis%2C_Vayigash.11?lang=bi