For Krysiak there are 195 on Yasni with different names.
Among the most common last names on Yasni Krysiak is on position 4482.
I believe it means "son of Krysia". The name "Krysia" is "Christine" in English, so the English equivalent of "Krysiak" would be "Christinson" or any variation of this. It also would therefore mean a member of the tribe or family "Krysia", or of "Krysia", as this was a common way to structure early surnames.
(Sent from: Tad Krysiak)