if you want to ignore the “first” element only then:
//li[position()>1]
or
(//a)[position()>1]
if you want the last only (like your example seems to suggest):
//li[last()]
or
(//a)[last()]
if you want to ignore the “first” element only then:
//li[position()>1]
or
(//a)[position()>1]
if you want the last only (like your example seems to suggest):
//li[last()]
or
(//a)[last()]