diff --git a/include/boost/fusion/support/detail/is_mpl_sequence.hpp b/include/boost/fusion/support/detail/is_mpl_sequence.hpp
index 24b86624..16b6db12 100644
--- a/include/boost/fusion/support/detail/is_mpl_sequence.hpp
+++ b/include/boost/fusion/support/detail/is_mpl_sequence.hpp
@@ -9,19 +9,17 @@
 #define FUSION_DETAIL_IS_MPL_SEQUENCE_29122006_1105
 
 #include <boost/fusion/support/config.hpp>
-#include <boost/fusion/support/sequence_base.hpp>
+#include <boost/fusion/support/detail/is_native_fusion_sequence.hpp>
 #include <boost/mpl/is_sequence.hpp>
 #include <boost/mpl/and.hpp>
 #include <boost/mpl/not.hpp>
-#include <boost/type_traits/is_complete.hpp>
-#include <boost/type_traits/is_convertible.hpp>
 
 namespace boost { namespace fusion { namespace detail
 {
     template <typename T>
     struct is_mpl_sequence
         : mpl::and_<
-            mpl::not_<mpl::and_<is_complete<T>, is_convertible<T, from_sequence_convertible_type> > >
+            mpl::not_<is_native_fusion_sequence<T> >
           , mpl::is_sequence<T> >
     {};
 }}}
diff --git a/include/boost/fusion/support/detail/is_native_fusion_sequence.hpp b/include/boost/fusion/support/detail/is_native_fusion_sequence.hpp
new file mode 100644
index 00000000..189c784d
--- /dev/null
+++ b/include/boost/fusion/support/detail/is_native_fusion_sequence.hpp
@@ -0,0 +1,27 @@
+/*=============================================================================
+    Copyright (c) 2018 Kohei Takahashi
+
+    Distributed under the Boost Software License, Version 1.0. (See accompanying
+    file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+==============================================================================*/
+#ifndef BOOST_FUSION_IS_NATIVE_FUSION_SEQUENCE
+#define BOOST_FUSION_IS_NATIVE_FUSION_SEQUENCE
+
+#include <boost/fusion/support/config.hpp>
+#include <boost/fusion/support/sequence_base.hpp>
+#include <boost/mpl/and.hpp>
+#include <boost/type_traits/is_complete.hpp>
+#include <boost/type_traits/is_convertible.hpp>
+
+namespace boost { namespace fusion { namespace detail
+{
+    template <typename Sequence>
+    struct is_native_fusion_sequence
+      : mpl::and_<
+          is_complete<Sequence>
+        , is_convertible<Sequence, detail::from_sequence_convertible_type>
+      >
+    {};
+}}}
+
+#endif
diff --git a/include/boost/fusion/support/is_sequence.hpp b/include/boost/fusion/support/is_sequence.hpp
index af7c84e1..95a9423f 100644
--- a/include/boost/fusion/support/is_sequence.hpp
+++ b/include/boost/fusion/support/is_sequence.hpp
@@ -10,13 +10,10 @@
 #include <boost/fusion/support/config.hpp>
 #include <boost/fusion/support/sequence_base.hpp>
 #include <boost/fusion/support/tag_of.hpp>
-#include <boost/mpl/and.hpp>
+#include <boost/fusion/support/detail/is_native_fusion_sequence.hpp>
 #include <boost/mpl/bool.hpp>
 #include <boost/mpl/is_sequence.hpp>
-#include <boost/mpl/or.hpp>
-#include <boost/type_traits/is_complete.hpp>
 #include <boost/type_traits/is_convertible.hpp>
-#include <boost/type_traits/is_same.hpp>
 
 namespace boost { namespace fusion
 {
@@ -69,13 +66,7 @@ namespace boost { namespace fusion
             >
         {};
 
-        template <typename Sequence, typename Enable = void>
-        struct is_native_fusion_sequence
-          : mpl::and_<
-            is_complete<Sequence>,
-            is_convertible<Sequence, fusion::detail::from_sequence_convertible_type>
-          >
-        {};
+        using detail::is_native_fusion_sequence;
     }
 }}