Help on marriage and the use of the term alias

I have been building our family tree for some years and I have come across
this document. It is a marriage entry for Pedro Antonio Ruiz alias Carrillo
Español to Maria Catharina Bueno. For over two hundred years Carrillo has
been the family name, now this appears. Does the word alias mean the same
then as today. Does it have other meanings. Pedro and Catharina went on to
have two sons carrying the name Carrillo Bueno. Should I now view the Ruiz
lineage from this point on into the past as my lineage? Am I reading and
translating this correctly? Can anyone help address my confusion? Thanks
Juan Manuel Carrillo

Here is the link to the document:
http://interactive.ancestry.com/61089/MM9.3.1_2FTH-1-18578-30740-31/1357663778?backlabel=ReturnRecord&backurl=http%3a%2f%2fsearch.ancestry.com%2f%2fcgi-bin%2fsse.dll%3findiv%3d1%26dbid%3d61089%26h%3d1357663778%26tid%3d30760563%26pid%3d12916287318%26hid%3d17969500846%26usePUB%3dtrue%26_phsrc%3dtRc709%26_phstart%3ddefault%26usePUBJs%3dtrue&ssrc=