diff --git a/lib/oga/css/parser.y b/lib/oga/css/parser.y
index cedad80..0aaa524 100644
--- a/lib/oga/css/parser.y
+++ b/lib/oga/css/parser.y
@@ -45,7 +45,7 @@ rule
     ;
 
   descendant_or_self
-    : node_test { s(:axis, 'descendant-or-self', val[0]) }
+    : node_test { s(:axis, 'descendant', val[0]) }
     ;
 
   axis
diff --git a/spec/oga/css/parser/axes_spec.rb b/spec/oga/css/parser/axes_spec.rb
index 80f655b..aef6330 100644
--- a/spec/oga/css/parser/axes_spec.rb
+++ b/spec/oga/css/parser/axes_spec.rb
@@ -3,53 +3,53 @@ require 'spec_helper'
 describe Oga::CSS::Parser do
   context 'axes' do
     example 'parse the > axis' do
-      parse_css('x > y').should == parse_xpath('descendant-or-self::x/y')
+      parse_css('x > y').should == parse_xpath('descendant::x/y')
     end
 
     example 'parse the > axis called on another > axis' do
-      parse_css('a > b > c').should == parse_xpath('descendant-or-self::a/b/c')
+      parse_css('a > b > c').should == parse_xpath('descendant::a/b/c')
     end
 
     example 'parse an > axis followed by an element with an ID' do
       parse_css('x > foo#bar').should == parse_xpath(
-        'descendant-or-self::x/foo[@id="bar"]'
+        'descendant::x/foo[@id="bar"]'
       )
     end
 
     example 'parse an > axis followed by an element with a class' do
       parse_css('x > foo.bar').should == parse_xpath(
-        'descendant-or-self::x/foo[contains(concat(" ", @class, " "), " bar ")]'
+        'descendant::x/foo[contains(concat(" ", @class, " "), " bar ")]'
       )
     end
 
     example 'parse the + axis' do
       parse_css('x + y').should == parse_xpath(
-        'descendant-or-self::x/following-sibling::*[1]/self::y'
+        'descendant::x/following-sibling::*[1]/self::y'
       )
     end
 
     example 'parse the + axis called on another + axis' do
       parse_css('a + b + c').should == parse_xpath(
-        'descendant-or-self::a/following-sibling::*[1]/self::b/' \
+        'descendant::a/following-sibling::*[1]/self::b/' \
           'following-sibling::*[1]/self::c'
       )
     end
 
     example 'parse the ~ axis' do
       parse_css('x ~ y').should == parse_xpath(
-        'descendant-or-self::x/following-sibling::y'
+        'descendant::x/following-sibling::y'
       )
     end
 
     example 'parse the ~ axis followed by another node test' do
       parse_css('x ~ y z').should == parse_xpath(
-        'descendant-or-self::x/following-sibling::y/descendant-or-self::z'
+        'descendant::x/following-sibling::y/descendant::z'
       )
     end
 
     example 'parse the ~ axis called on another ~ axis' do
       parse_css('a ~ b ~ c').should == parse_xpath(
-        'descendant-or-self::a/following-sibling::b/following-sibling::c'
+        'descendant::a/following-sibling::b/following-sibling::c'
       )
     end
   end
diff --git a/spec/oga/css/parser/classes_spec.rb b/spec/oga/css/parser/classes_spec.rb
index 8489d97..5700b3a 100644
--- a/spec/oga/css/parser/classes_spec.rb
+++ b/spec/oga/css/parser/classes_spec.rb
@@ -4,26 +4,26 @@ describe Oga::CSS::Parser do
   context 'classes' do
     example 'parse a class selector' do
       parse_css('.foo').should == parse_xpath(
-        'descendant-or-self::*[contains(concat(" ", @class, " "), " foo ")]'
+        'descendant::*[contains(concat(" ", @class, " "), " foo ")]'
       )
     end
 
     example 'parse a selector for an element with a class' do
       parse_css('foo.bar').should == parse_xpath(
-        'descendant-or-self::foo[contains(concat(" ", @class, " "), " bar ")]'
+        'descendant::foo[contains(concat(" ", @class, " "), " bar ")]'
       )
     end
 
     example 'parse a selector using multiple classes' do
       parse_css('.foo.bar').should == parse_xpath(
-        'descendant-or-self::*[contains(concat(" ", @class, " "), " foo ") ' \
+        'descendant::*[contains(concat(" ", @class, " "), " foo ") ' \
           'and contains(concat(" ", @class, " "), " bar ")]'
       )
     end
 
     example 'parse a selector using a class and an ID' do
       parse_css('#foo.bar').should == parse_xpath(
-        'descendant-or-self::*[@id="foo" and ' \
+        'descendant::*[@id="foo" and ' \
           'contains(concat(" ", @class, " "), " bar ")]'
       )
     end
diff --git a/spec/oga/css/parser/ids_spec.rb b/spec/oga/css/parser/ids_spec.rb
index 7e12c4a..7fba027 100644
--- a/spec/oga/css/parser/ids_spec.rb
+++ b/spec/oga/css/parser/ids_spec.rb
@@ -3,26 +3,22 @@ require 'spec_helper'
 describe Oga::CSS::Parser do
   context 'IDs' do
     example 'parse an ID selector' do
-      parse_css('#foo').should == parse_xpath(
-        'descendant-or-self::*[@id="foo"]'
-      )
+      parse_css('#foo').should == parse_xpath('descendant::*[@id="foo"]')
     end
 
     example 'parse a selector for an element with an ID' do
-      parse_css('foo#bar').should == parse_xpath(
-        'descendant-or-self::foo[@id="bar"]'
-      )
+      parse_css('foo#bar').should == parse_xpath('descendant::foo[@id="bar"]')
     end
 
     example 'parse a selector using multiple IDs' do
       parse_css('#foo#bar').should == parse_xpath(
-        'descendant-or-self::*[@id="foo" and @id="bar"]'
+        'descendant::*[@id="foo" and @id="bar"]'
       )
     end
 
     example 'parse a selector using an ID and a class' do
       parse_css('.foo#bar').should == parse_xpath(
-        'descendant-or-self::*[contains(concat(" ", @class, " "), " foo ") ' \
+        'descendant::*[contains(concat(" ", @class, " "), " foo ") ' \
           'and @id="bar"]'
       )
     end
diff --git a/spec/oga/css/parser/operators_spec.rb b/spec/oga/css/parser/operators_spec.rb
index 514e78f..9bf059d 100644
--- a/spec/oga/css/parser/operators_spec.rb
+++ b/spec/oga/css/parser/operators_spec.rb
@@ -3,40 +3,38 @@ require 'spec_helper'
 describe Oga::CSS::Parser do
   context 'operators' do
     example 'parse the = operator' do
-      parse_css('x[a="b"]').should == parse_xpath(
-        'descendant-or-self::x[@a="b"]'
-      )
+      parse_css('x[a="b"]').should == parse_xpath('descendant::x[@a="b"]')
     end
 
     example 'parse the ~= operator' do
       parse_css('x[a~="b"]').should == parse_xpath(
-        'descendant-or-self::x[contains(concat(" ", @a, " "), ' \
+        'descendant::x[contains(concat(" ", @a, " "), ' \
           'concat(" ", "b", " "))]'
       )
     end
 
     example 'parse the ^= operator' do
       parse_css('x[a^="b"]').should == parse_xpath(
-        'descendant-or-self::x[starts-with(@a, "b")]'
+        'descendant::x[starts-with(@a, "b")]'
       )
     end
 
     example 'parse the $= operator' do
       parse_css('x[a$="b"]').should == parse_xpath(
-        'descendant-or-self::x[substring(@a, string-length(@a) - ' \
+        'descendant::x[substring(@a, string-length(@a) - ' \
           'string-length("b") + 1, string-length("b")) = "b"]'
       )
     end
 
     example 'parse the *= operator' do
       parse_css('x[a*="b"]').should == parse_xpath(
-        'descendant-or-self::x[contains(@a, "b")]'
+        'descendant::x[contains(@a, "b")]'
       )
     end
 
     example 'parse the |= operator' do
       parse_css('x[a|="b"]').should == parse_xpath(
-        'descendant-or-self::x[@a = "b" or starts-with(@a, concat("b", "-"))]'
+        'descendant::x[@a = "b" or starts-with(@a, concat("b", "-"))]'
       )
     end
   end
diff --git a/spec/oga/css/parser/paths_spec.rb b/spec/oga/css/parser/paths_spec.rb
index 42849ae..f21f41f 100644
--- a/spec/oga/css/parser/paths_spec.rb
+++ b/spec/oga/css/parser/paths_spec.rb
@@ -3,12 +3,12 @@ require 'spec_helper'
 describe Oga::CSS::Parser do
   context 'paths' do
     example 'parse a single path' do
-      parse_css('foo').should == parse_xpath('descendant-or-self::foo')
+      parse_css('foo').should == parse_xpath('descendant::foo')
     end
 
     example 'parse a path using two selectors' do
       parse_css('foo bar').should == parse_xpath(
-        'descendant-or-self::foo/descendant-or-self::bar'
+        'descendant::foo/descendant::bar'
       )
     end
   end
diff --git a/spec/oga/css/parser/predicates_spec.rb b/spec/oga/css/parser/predicates_spec.rb
index 003c616..a6214ad 100644
--- a/spec/oga/css/parser/predicates_spec.rb
+++ b/spec/oga/css/parser/predicates_spec.rb
@@ -3,20 +3,18 @@ require 'spec_helper'
 describe Oga::CSS::Parser do
   context 'predicates' do
     example 'parse a predicate' do
-      parse_css('foo[bar]').should == parse_xpath(
-        'descendant-or-self::foo[@bar]'
-      )
+      parse_css('foo[bar]').should == parse_xpath('descendant::foo[@bar]')
     end
 
     example 'parse a node test followed by a node test with a predicate' do
       parse_css('foo bar[baz]').should == parse_xpath(
-        'descendant-or-self::foo/descendant-or-self::bar[@baz]'
+        'descendant::foo/descendant::bar[@baz]'
       )
     end
 
     example 'parse a predicate testing an attribute value' do
       parse_css('foo[bar="baz"]').should == parse_xpath(
-        'descendant-or-self::foo[@bar="baz"]'
+        'descendant::foo[@bar="baz"]'
       )
     end
   end
diff --git a/spec/oga/css/parser/pseudo_classes/empty_spec.rb b/spec/oga/css/parser/pseudo_classes/empty_spec.rb
index b487f1d..c99749c 100644
--- a/spec/oga/css/parser/pseudo_classes/empty_spec.rb
+++ b/spec/oga/css/parser/pseudo_classes/empty_spec.rb
@@ -3,9 +3,7 @@ require 'spec_helper'
 describe Oga::CSS::Parser do
   context ':empty pseudo class' do
     example 'parse the :empty pseudo class' do
-      parse_css(':empty').should == parse_xpath(
-        'descendant-or-self::*[not(node())]'
-      )
+      parse_css(':empty').should == parse_xpath('descendant::*[not(node())]')
     end
   end
 end
diff --git a/spec/oga/css/parser/pseudo_classes/first_child_spec.rb b/spec/oga/css/parser/pseudo_classes/first_child_spec.rb
index 6acb75f..533edb6 100644
--- a/spec/oga/css/parser/pseudo_classes/first_child_spec.rb
+++ b/spec/oga/css/parser/pseudo_classes/first_child_spec.rb
@@ -4,7 +4,7 @@ describe Oga::CSS::Parser do
   context ':first-child pseudo class' do
     example 'parse the :first-child pseudo class' do
       parse_css(':first-child').should == parse_xpath(
-        'descendant-or-self::*[count(preceding-sibling::*) = 0]'
+        'descendant::*[count(preceding-sibling::*) = 0]'
       )
     end
   end
diff --git a/spec/oga/css/parser/pseudo_classes/first_of_type_spec.rb b/spec/oga/css/parser/pseudo_classes/first_of_type_spec.rb
index 4356bb7..5e903a8 100644
--- a/spec/oga/css/parser/pseudo_classes/first_of_type_spec.rb
+++ b/spec/oga/css/parser/pseudo_classes/first_of_type_spec.rb
@@ -4,7 +4,7 @@ describe Oga::CSS::Parser do
   context ':first-of-type pseudo class' do
     example 'parse the :first-of-type pseudo class' do
       parse_css(':first-of-type').should == parse_xpath(
-        'descendant-or-self::*[position() = 1]'
+        'descendant::*[position() = 1]'
       )
     end
   end
diff --git a/spec/oga/css/parser/pseudo_classes/last_child_spec.rb b/spec/oga/css/parser/pseudo_classes/last_child_spec.rb
index ae94ed1..13af10b 100644
--- a/spec/oga/css/parser/pseudo_classes/last_child_spec.rb
+++ b/spec/oga/css/parser/pseudo_classes/last_child_spec.rb
@@ -4,7 +4,7 @@ describe Oga::CSS::Parser do
   context ':last-child pseudo class' do
     example 'parse the :last-child pseudo class' do
       parse_css(':last-child').should == parse_xpath(
-        'descendant-or-self::*[count(following-sibling::*) = 0]'
+        'descendant::*[count(following-sibling::*) = 0]'
       )
     end
   end
diff --git a/spec/oga/css/parser/pseudo_classes/last_of_type_spec.rb b/spec/oga/css/parser/pseudo_classes/last_of_type_spec.rb
index 52678ba..64f1d78 100644
--- a/spec/oga/css/parser/pseudo_classes/last_of_type_spec.rb
+++ b/spec/oga/css/parser/pseudo_classes/last_of_type_spec.rb
@@ -4,7 +4,7 @@ describe Oga::CSS::Parser do
   context ':last-of-type pseudo class' do
     example 'parse the :last-of-type pseudo class' do
       parse_css(':last-of-type').should == parse_xpath(
-        'descendant-or-self::*[position() = last()]'
+        'descendant::*[position() = last()]'
       )
     end
   end
diff --git a/spec/oga/css/parser/pseudo_classes/nth_child_spec.rb b/spec/oga/css/parser/pseudo_classes/nth_child_spec.rb
index 3fe9217..12d3d5c 100644
--- a/spec/oga/css/parser/pseudo_classes/nth_child_spec.rb
+++ b/spec/oga/css/parser/pseudo_classes/nth_child_spec.rb
@@ -4,57 +4,57 @@ describe Oga::CSS::Parser do
   context ':nth-child pseudo class' do
     example 'parse the x:nth-child(1) pseudo class' do
       parse_css('x:nth-child(1)').should == parse_xpath(
-        'descendant-or-self::x[count(preceding-sibling::*) = 0]'
+        'descendant::x[count(preceding-sibling::*) = 0]'
       )
     end
 
     example 'parse the :nth-child(1) pseudo class' do
       parse_css(':nth-child(1)').should == parse_xpath(
-        'descendant-or-self::*[count(preceding-sibling::*) = 0]'
+        'descendant::*[count(preceding-sibling::*) = 0]'
       )
     end
 
     example 'parse the :nth-child(2) pseudo class' do
       parse_css(':nth-child(2)').should == parse_xpath(
-        'descendant-or-self::*[count(preceding-sibling::*) = 1]'
+        'descendant::*[count(preceding-sibling::*) = 1]'
       )
     end
 
     example 'parse the x:nth-child(even) pseudo class' do
       parse_css('x:nth-child(even)').should == parse_xpath(
-        'descendant-or-self::x[((count(preceding-sibling::*) + 1) mod 2) = 0]'
+        'descendant::x[((count(preceding-sibling::*) + 1) mod 2) = 0]'
       )
     end
 
     example 'parse the x:nth-child(odd) pseudo class' do
       parse_css('x:nth-child(odd)').should == parse_xpath(
-        'descendant-or-self::x[(count(preceding-sibling::*) + 1) >= 1 ' \
+        'descendant::x[(count(preceding-sibling::*) + 1) >= 1 ' \
           'and (((count(preceding-sibling::*) + 1) - 1) mod 2) = 0]'
       )
     end
 
     example 'parse the x:nth-child(n) pseudo class' do
       parse_css('x:nth-child(n)').should == parse_xpath(
-        'descendant-or-self::x[((count(preceding-sibling::*) + 1) mod 1) = 0]'
+        'descendant::x[((count(preceding-sibling::*) + 1) mod 1) = 0]'
       )
     end
 
     example 'parse the x:nth-child(-n) pseudo class' do
       parse_css('x:nth-child(-n)').should == parse_xpath(
-        'descendant-or-self::x[((count(preceding-sibling::*) + 1) mod 1) = 0]'
+        'descendant::x[((count(preceding-sibling::*) + 1) mod 1) = 0]'
       )
     end
 
     example 'parse the x:nth-child(-n+6) pseudo class' do
       parse_css('x:nth-child(-n+6)').should == parse_xpath(
-        'descendant-or-self::x[((count(preceding-sibling::*) + 1) <= 6) ' \
+        'descendant::x[((count(preceding-sibling::*) + 1) <= 6) ' \
           'and (((count(preceding-sibling::*) + 1) - 6) mod 1) = 0]'
       )
     end
 
     example 'parse the x:nth-child(n+5) pseudo class' do
       parse_css('x:nth-child(n+5)').should == parse_xpath(
-        'descendant-or-self::x[(count(preceding-sibling::*) + 1) >= 5 ' \
+        'descendant::x[(count(preceding-sibling::*) + 1) >= 5 ' \
           'and (((count(preceding-sibling::*) + 1) - 5) mod 1) = 0]'
       )
     end
@@ -65,28 +65,28 @@ describe Oga::CSS::Parser do
 
     example 'parse the x:nth-child(2n+1) pseudo class' do
       parse_css('x:nth-child(2n+1)').should == parse_xpath(
-        'descendant-or-self::x[(count(preceding-sibling::*) + 1) >= 1 ' \
+        'descendant::x[(count(preceding-sibling::*) + 1) >= 1 ' \
           'and (((count(preceding-sibling::*) + 1) - 1) mod 2) = 0]'
       )
     end
 
     example 'parse the x:nth-child(3n+1) pseudo class' do
       parse_css('x:nth-child(3n+1)').should == parse_xpath(
-        'descendant-or-self::x[(count(preceding-sibling::*) + 1) >= 1 ' \
+        'descendant::x[(count(preceding-sibling::*) + 1) >= 1 ' \
           'and (((count(preceding-sibling::*) + 1) - 1) mod 3) = 0]'
       )
     end
 
     example 'parse the x:nth-child(2n-6) pseudo class' do
       parse_css('x:nth-child(2n-6)').should == parse_xpath(
-        'descendant-or-self::x[(count(preceding-sibling::*) + 1) >= 2 ' \
+        'descendant::x[(count(preceding-sibling::*) + 1) >= 2 ' \
           'and (((count(preceding-sibling::*) + 1) - 2) mod 2) = 0]'
       )
     end
 
     example 'parse the x:nth-child(-2n+6) pseudo class' do
       parse_css('x:nth-child(-2n+6)').should == parse_xpath(
-        'descendant-or-self::x[((count(preceding-sibling::*) + 1) <= 6) ' \
+        'descendant::x[((count(preceding-sibling::*) + 1) <= 6) ' \
           'and (((count(preceding-sibling::*) + 1) - 6) mod 2) = 0]'
       )
     end
diff --git a/spec/oga/css/parser/pseudo_classes/nth_last_child_spec.rb b/spec/oga/css/parser/pseudo_classes/nth_last_child_spec.rb
index 8212191..da48895 100644
--- a/spec/oga/css/parser/pseudo_classes/nth_last_child_spec.rb
+++ b/spec/oga/css/parser/pseudo_classes/nth_last_child_spec.rb
@@ -4,50 +4,50 @@ describe Oga::CSS::Parser do
   context ':nth-last-child pseudo class' do
     example 'parse the x:nth-last-child(1) pseudo class' do
       parse_css('x:nth-last-child(1)').should == parse_xpath(
-        'descendant-or-self::x[count(following-sibling::*) = 0]'
+        'descendant::x[count(following-sibling::*) = 0]'
       )
     end
 
     example 'parse the :nth-last-child(1) pseudo class' do
       parse_css(':nth-last-child(1)').should == parse_xpath(
-        'descendant-or-self::*[count(following-sibling::*) = 0]'
+        'descendant::*[count(following-sibling::*) = 0]'
       )
     end
 
     example 'parse the :nth-last-child(2) pseudo class' do
       parse_css(':nth-last-child(2)').should == parse_xpath(
-        'descendant-or-self::*[count(following-sibling::*) = 1]'
+        'descendant::*[count(following-sibling::*) = 1]'
       )
     end
 
     example 'parse the x:nth-last-child(even) pseudo class' do
       parse_css('x:nth-last-child(even)').should == parse_xpath(
-        'descendant-or-self::x[((count(following-sibling::*) + 1) mod 2) = 0]'
+        'descendant::x[((count(following-sibling::*) + 1) mod 2) = 0]'
       )
     end
 
     example 'parse the x:nth-last-child(odd) pseudo class' do
       parse_css('x:nth-last-child(odd)').should == parse_xpath(
-        'descendant-or-self::x[(count(following-sibling::*) + 1) >= 1 ' \
+        'descendant::x[(count(following-sibling::*) + 1) >= 1 ' \
           'and (((count(following-sibling::*) + 1) - 1) mod 2) = 0]'
       )
     end
 
     example 'parse the x:nth-last-child(n) pseudo class' do
       parse_css('x:nth-last-child(n)').should == parse_xpath(
-        'descendant-or-self::x[((count(following-sibling::*) + 1) mod 1) = 0]'
+        'descendant::x[((count(following-sibling::*) + 1) mod 1) = 0]'
       )
     end
 
     example 'parse the x:nth-last-child(-n) pseudo class' do
       parse_css('x:nth-last-child(-n)').should == parse_xpath(
-        'descendant-or-self::x[((count(following-sibling::*) + 1) mod 1) = 0]'
+        'descendant::x[((count(following-sibling::*) + 1) mod 1) = 0]'
       )
     end
 
     example 'parse the x:nth-last-child(-n+6) pseudo class' do
       parse_css('x:nth-last-child(-n+6)').should == parse_xpath(
-        'descendant-or-self::x[((count(following-sibling::*) + 1) <= 6) ' \
+        'descendant::x[((count(following-sibling::*) + 1) <= 6) ' \
           'and (((count(following-sibling::*) + 1) - 6) mod 1) = 0]'
       )
     end
@@ -60,28 +60,28 @@ describe Oga::CSS::Parser do
 
     example 'parse the x:nth-last-child(2n+1) pseudo class' do
       parse_css('x:nth-last-child(2n+1)').should == parse_xpath(
-        'descendant-or-self::x[(count(following-sibling::*) + 1) >= 1 ' \
+        'descendant::x[(count(following-sibling::*) + 1) >= 1 ' \
           'and (((count(following-sibling::*) + 1) - 1) mod 2) = 0]'
       )
     end
 
     example 'parse the x:nth-last-child(2n-6) pseudo class' do
       parse_css('x:nth-last-child(2n-6)').should == parse_xpath(
-        'descendant-or-self::x[(count(following-sibling::*) + 1) >= 2 ' \
+        'descendant::x[(count(following-sibling::*) + 1) >= 2 ' \
           'and (((count(following-sibling::*) + 1) - 2) mod 2) = 0]'
       )
     end
 
     example 'parse the x:nth-last-child(-2n-6) pseudo class' do
       parse_css('x:nth-last-child(-2n-6)').should == parse_xpath(
-        'descendant-or-self::x[((count(following-sibling::*) + 1) <= -2) ' \
+        'descendant::x[((count(following-sibling::*) + 1) <= -2) ' \
           'and (((count(following-sibling::*) + 1) - -2) mod 2) = 0]'
       )
     end
 
     example 'parse the x:nth-last-child(-2n+6) pseudo class' do
       parse_css('x:nth-last-child(-2n+6)').should == parse_xpath(
-        'descendant-or-self::x[((count(following-sibling::*) + 1) <= 6) ' \
+        'descendant::x[((count(following-sibling::*) + 1) <= 6) ' \
           'and (((count(following-sibling::*) + 1) - 6) mod 2) = 0]'
       )
     end
diff --git a/spec/oga/css/parser/pseudo_classes/nth_last_of_type_spec.rb b/spec/oga/css/parser/pseudo_classes/nth_last_of_type_spec.rb
index 5091acb..15d3d28 100644
--- a/spec/oga/css/parser/pseudo_classes/nth_last_of_type_spec.rb
+++ b/spec/oga/css/parser/pseudo_classes/nth_last_of_type_spec.rb
@@ -4,106 +4,106 @@ describe Oga::CSS::Parser do
   context ':nth-last-of-type pseudo class' do
     example 'parse the :nth-last-of-type(1) pseudo class' do
       parse_css(':nth-last-of-type(1)').should == parse_xpath(
-        'descendant-or-self::*[(last() - position() + 1) = 1]'
+        'descendant::*[(last() - position() + 1) = 1]'
       )
     end
 
     example 'parse the :nth-last-of-type(2n) pseudo class' do
       parse_css(':nth-last-of-type(2n)').should == parse_xpath(
-        'descendant-or-self::*[((last() - position() + 1) mod 2) = 0]'
+        'descendant::*[((last() - position() + 1) mod 2) = 0]'
       )
     end
 
     example 'parse the :nth-last-of-type(3n) pseudo class' do
       parse_css(':nth-last-of-type(3n)').should == parse_xpath(
-        'descendant-or-self::*[((last() - position() + 1) mod 3) = 0]'
+        'descendant::*[((last() - position() + 1) mod 3) = 0]'
       )
     end
 
     example 'parse the :nth-last-of-type(2n+5) pseudo class' do
       parse_css(':nth-last-of-type(2n+5)').should == parse_xpath(
-        'descendant-or-self::*[((last() - position() + 1) >= 5) ' \
+        'descendant::*[((last() - position() + 1) >= 5) ' \
           'and ((((last() - position() + 1) - 5) mod 2) = 0)]'
       )
     end
 
     example 'parse the :nth-last-of-type(3n+5) pseudo class' do
       parse_css(':nth-last-of-type(3n+5)').should == parse_xpath(
-        'descendant-or-self::*[((last() - position() + 1) >= 5) ' \
+        'descendant::*[((last() - position() + 1) >= 5) ' \
           'and ((((last() - position() + 1) - 5) mod 3) = 0)]'
       )
     end
 
     example 'parse the :nth-last-of-type(2n-5) pseudo class' do
       parse_css(':nth-last-of-type(2n-5)').should == parse_xpath(
-        'descendant-or-self::*[((last() - position() + 1) >= 1) ' \
+        'descendant::*[((last() - position() + 1) >= 1) ' \
           'and ((((last() - position() + 1) - 1) mod 2) = 0)]'
       )
     end
 
     example 'parse the :nth-last-of-type(2n-6) pseudo class' do
       parse_css(':nth-last-of-type(2n-6)').should == parse_xpath(
-        'descendant-or-self::*[((last() - position() + 1) >= 2) ' \
+        'descendant::*[((last() - position() + 1) >= 2) ' \
           'and ((((last() - position() + 1) - 2) mod 2) = 0)]'
       )
     end
 
     example 'parse the :nth-last-of-type(-2n+5) pseudo class' do
       parse_css(':nth-last-of-type(-2n+5)').should == parse_xpath(
-        'descendant-or-self::*[((last() - position() + 1) <= 5) ' \
+        'descendant::*[((last() - position() + 1) <= 5) ' \
           'and (((last() - position() + 1) - 5) mod 2) = 0]'
       )
     end
 
     example 'parse the :nth-last-of-type(-2n-5) pseudo class' do
       parse_css(':nth-last-of-type(-2n-5)').should == parse_xpath(
-        'descendant-or-self::*[((last() - position() + 1) <= -1) ' \
+        'descendant::*[((last() - position() + 1) <= -1) ' \
           'and (((last() - position() + 1) - -1) mod 2) = 0]'
       )
     end
 
     example 'parse the :nth-last-of-type(-2n-6) pseudo class' do
       parse_css(':nth-last-of-type(-2n-6)').should == parse_xpath(
-        'descendant-or-self::*[((last() - position() + 1) <= -2) ' \
+        'descendant::*[((last() - position() + 1) <= -2) ' \
           'and (((last() - position() + 1) - -2) mod 2) = 0]'
       )
     end
 
     example 'parse the :nth-last-of-type(even) pseudo class' do
       parse_css(':nth-last-of-type(even)').should == parse_xpath(
-        'descendant-or-self::*[((last() - position() + 1) mod 2) = 0]'
+        'descendant::*[((last() - position() + 1) mod 2) = 0]'
       )
     end
 
     example 'parse the :nth-last-of-type(odd) pseudo class' do
       parse_css(':nth-last-of-type(odd)').should == parse_xpath(
-        'descendant-or-self::*[((last() - position() + 1) >= 1) ' \
+        'descendant::*[((last() - position() + 1) >= 1) ' \
           'and ((((last() - position() + 1) - 1) mod 2) = 0)]'
       )
     end
 
     example 'parse the :nth-last-of-type(n) pseudo class' do
       parse_css(':nth-last-of-type(n)').should == parse_xpath(
-        'descendant-or-self::*[((last() - position() + 1) mod 1) = 0]'
+        'descendant::*[((last() - position() + 1) mod 1) = 0]'
       )
     end
 
     example 'parse the :nth-last-of-type(n+5) pseudo class' do
       parse_css(':nth-last-of-type(n+5)').should == parse_xpath(
-        'descendant-or-self::*[(last() - position() + 1) >= 5 ' \
+        'descendant::*[(last() - position() + 1) >= 5 ' \
           'and (((last() - position() + 1) - 5) mod 1) = 0]'
       )
     end
 
     example 'parse the :nth-last-of-type(-n) pseudo class' do
       parse_css(':nth-last-of-type(-n)').should == parse_xpath(
-        'descendant-or-self::*[((last() - position() + 1) mod 1) = 0]'
+        'descendant::*[((last() - position() + 1) mod 1) = 0]'
       )
     end
 
     example 'parse the :nth-last-of-type(-n+5) pseudo class' do
       parse_css(':nth-last-of-type(-n+5)').should == parse_xpath(
-        'descendant-or-self::*[((last() - position() + 1) <= 5) ' \
+        'descendant::*[((last() - position() + 1) <= 5) ' \
           'and (((last() - position() + 1) - 5) mod 1) = 0]'
       )
     end
diff --git a/spec/oga/css/parser/pseudo_classes/nth_of_type_spec.rb b/spec/oga/css/parser/pseudo_classes/nth_of_type_spec.rb
index 6d41585..f6238af 100644
--- a/spec/oga/css/parser/pseudo_classes/nth_of_type_spec.rb
+++ b/spec/oga/css/parser/pseudo_classes/nth_of_type_spec.rb
@@ -4,106 +4,106 @@ describe Oga::CSS::Parser do
   context ':nth-of-type pseudo class' do
     example 'parse the :nth-of-type(1) pseudo class' do
       parse_css(':nth-of-type(1)').should == parse_xpath(
-        'descendant-or-self::*[position() = 1]'
+        'descendant::*[position() = 1]'
       )
     end
 
     example 'parse the :nth-of-type(2n) pseudo class' do
       parse_css(':nth-of-type(2n)').should == parse_xpath(
-        'descendant-or-self::*[(position() mod 2) = 0]'
+        'descendant::*[(position() mod 2) = 0]'
       )
     end
 
     example 'parse the :nth-of-type(3n) pseudo class' do
       parse_css(':nth-of-type(3n)').should == parse_xpath(
-        'descendant-or-self::*[(position() mod 3) = 0]'
+        'descendant::*[(position() mod 3) = 0]'
       )
     end
 
     example 'parse the :nth-of-type(2n+5) pseudo class' do
       parse_css(':nth-of-type(2n+5)').should == parse_xpath(
-        'descendant-or-self::*[(position() >= 5) ' \
+        'descendant::*[(position() >= 5) ' \
           'and (((position() - 5) mod 2) = 0)]'
       )
     end
 
     example 'parse the :nth-of-type(3n+5) pseudo class' do
       parse_css(':nth-of-type(3n+5)').should == parse_xpath(
-        'descendant-or-self::*[(position() >= 5) ' \
+        'descendant::*[(position() >= 5) ' \
           'and (((position() - 5) mod 3) = 0)]'
       )
     end
 
     example 'parse the :nth-of-type(2n-5) pseudo class' do
       parse_css(':nth-of-type(2n-5)').should == parse_xpath(
-        'descendant-or-self::*[(position() >= 1) ' \
+        'descendant::*[(position() >= 1) ' \
           'and (((position() - 1) mod 2) = 0)]'
       )
     end
 
     example 'parse the :nth-of-type(2n-6) pseudo class' do
       parse_css(':nth-of-type(2n-6)').should == parse_xpath(
-        'descendant-or-self::*[(position() >= 2) ' \
+        'descendant::*[(position() >= 2) ' \
           'and (((position() - 2) mod 2) = 0)]'
       )
     end
 
     example 'parse the :nth-of-type(-2n+5) pseudo class' do
       parse_css(':nth-of-type(-2n+5)').should == parse_xpath(
-        'descendant-or-self::*[(position() <= 5) ' \
+        'descendant::*[(position() <= 5) ' \
           'and ((position() - 5) mod 2) = 0]'
       )
     end
 
     example 'parse the :nth-of-type(-2n-5) pseudo class' do
       parse_css(':nth-of-type(-2n-5)').should == parse_xpath(
-        'descendant-or-self::*[(position() <= -1) ' \
+        'descendant::*[(position() <= -1) ' \
           'and ((position() - -1) mod 2) = 0]'
       )
     end
 
     example 'parse the :nth-of-type(-2n-6) pseudo class' do
       parse_css(':nth-of-type(-2n-6)').should == parse_xpath(
-        'descendant-or-self::*[(position() <= -2) ' \
+        'descendant::*[(position() <= -2) ' \
           'and ((position() - -2) mod 2) = 0]'
       )
     end
 
     example 'parse the :nth-of-type(even) pseudo class' do
       parse_css(':nth-of-type(even)').should == parse_xpath(
-        'descendant-or-self::*[(position() mod 2) = 0]'
+        'descendant::*[(position() mod 2) = 0]'
       )
     end
 
     example 'parse the :nth-of-type(odd) pseudo class' do
       parse_css(':nth-of-type(odd)').should == parse_xpath(
-        'descendant-or-self::*[(position() >= 1) ' \
+        'descendant::*[(position() >= 1) ' \
           'and (((position() - 1) mod 2) = 0)]'
       )
     end
 
     example 'parse the :nth-of-type(n) pseudo class' do
       parse_css(':nth-of-type(n)').should == parse_xpath(
-        'descendant-or-self::*[(position() mod 1) =0]'
+        'descendant::*[(position() mod 1) =0]'
       )
     end
 
     example 'parse the :nth-of-type(n+5) pseudo class' do
       parse_css(':nth-of-type(n+5)').should == parse_xpath(
-        'descendant-or-self::*[position() >= 5 ' \
+        'descendant::*[position() >= 5 ' \
           'and ((position() - 5) mod 1) = 0]'
       )
     end
 
     example 'parse the :nth-of-type(-n) pseudo class' do
       parse_css(':nth-of-type(-n)').should == parse_xpath(
-        'descendant-or-self::*[(position() mod 1) = 0]'
+        'descendant::*[(position() mod 1) = 0]'
       )
     end
 
     example 'parse the :nth-of-type(-n+5) pseudo class' do
       parse_css(':nth-of-type(-n+5)').should == parse_xpath(
-        'descendant-or-self::*[(position() <= 5) ' \
+        'descendant::*[(position() <= 5) ' \
           'and ((position() - 5) mod 1) = 0]'
       )
     end
diff --git a/spec/oga/css/parser/pseudo_classes/only_child_spec.rb b/spec/oga/css/parser/pseudo_classes/only_child_spec.rb
index c14de75..e095233 100644
--- a/spec/oga/css/parser/pseudo_classes/only_child_spec.rb
+++ b/spec/oga/css/parser/pseudo_classes/only_child_spec.rb
@@ -4,7 +4,7 @@ describe Oga::CSS::Parser do
   context ':only-child pseudo class' do
     example 'parse the :only-child pseudo class' do
       parse_css(':only-child').should == parse_xpath(
-        'descendant-or-self::*[count(preceding-sibling::*) = 0 ' \
+        'descendant::*[count(preceding-sibling::*) = 0 ' \
           'and count(following-sibling::*) = 0]'
       )
     end
diff --git a/spec/oga/css/parser/pseudo_classes/only_of_type_spec.rb b/spec/oga/css/parser/pseudo_classes/only_of_type_spec.rb
index 2c06f94..3e09a78 100644
--- a/spec/oga/css/parser/pseudo_classes/only_of_type_spec.rb
+++ b/spec/oga/css/parser/pseudo_classes/only_of_type_spec.rb
@@ -4,7 +4,7 @@ describe Oga::CSS::Parser do
   context ':only-of-type pseudo class' do
     example 'parse the :only-of-type pseudo class' do
       parse_css(':only-of-type').should == parse_xpath(
-        'descendant-or-self::*[last() = 1]'
+        'descendant::*[last() = 1]'
       )
     end
   end
diff --git a/spec/oga/css/parser/pseudo_classes/root_spec.rb b/spec/oga/css/parser/pseudo_classes/root_spec.rb
index cfe5606..4e1db6a 100644
--- a/spec/oga/css/parser/pseudo_classes/root_spec.rb
+++ b/spec/oga/css/parser/pseudo_classes/root_spec.rb
@@ -3,15 +3,11 @@ require 'spec_helper'
 describe Oga::CSS::Parser do
   context ':root pseudo class' do
     example 'parse the x:root pseudo class' do
-      parse_css('x:root').should == parse_xpath(
-        'descendant-or-self::x[not(parent::*)]'
-      )
+      parse_css('x:root').should == parse_xpath('descendant::x[not(parent::*)]')
     end
 
     example 'parse the :root pseudo class' do
-      parse_css(':root').should == parse_xpath(
-        'descendant-or-self::*[not(parent::*)]'
-      )
+      parse_css(':root').should == parse_xpath('descendant::*[not(parent::*)]')
     end
   end
 end
diff --git a/spec/oga/css/parser/wildcards_spec.rb b/spec/oga/css/parser/wildcards_spec.rb
index 04f5f3a..9a4c734 100644
--- a/spec/oga/css/parser/wildcards_spec.rb
+++ b/spec/oga/css/parser/wildcards_spec.rb
@@ -3,15 +3,15 @@ require 'spec_helper'
 describe Oga::CSS::Parser do
   context 'wildcards' do
     example 'parse a wildcard name test' do
-      parse_css('*').should == parse_xpath('descendant-or-self::*')
+      parse_css('*').should == parse_xpath('descendant::*')
     end
 
     example 'parse a wildcard namespace test' do
-      parse_css('*|foo').should == parse_xpath('descendant-or-self::*:foo')
+      parse_css('*|foo').should == parse_xpath('descendant::*:foo')
     end
 
     example 'parse a wildcard namespace and name test' do
-      parse_css('*|*').should == parse_xpath('descendant-or-self::*:*')
+      parse_css('*|*').should == parse_xpath('descendant::*:*')
     end
   end
 end