SQL Server - system base table: sys.syspalnames (?)

sys.syspalnames seems(!) to be a system base table. I am not entierly sure, though, because I cannot find the name in sys.sysobjects (with or without xtype = 'S').

class = OBTY

Select records with class = 'OBTY' return the object types and descriptions (as found, for example, in the columns type_desc and type in sys.all_objects).

select 
   name,
   value
from
   sys.syspalnames where class = 'OBTY'
order by
   name;