-\def\Mapsto{\Mapstochar\mathrel{\kern-2mu}\Rightarrow} stmaryrd
-\def\mapsfrom{\leftarrow\kern-9mu\mapsfromchar} stmaryrd
-\def\Mapsfrom{\Leftarrow\kern-9mu\Mapsfromchar} stmaryrd
-\def\Longmapsto{\Mapstochar\Longrightarrow} stmaryrd
-\def\longmapsfrom{\longleftarrow\mapsfromchar} stmaryrd
-\def\Longmapsfrom{\Longleftarrow\mathrel{\kern1mu}\Mapsfromchar} stmaryrd
+\def\Mapsto{\Mapstochar\mathrel\Rightarrow} mathrel ⤇ stmaryrd
+\def\mapsfrom{\leftarrow\kern-9mu\mapsfromchar} mathrel ↤ stmaryrd
+\def\Mapsfrom{\Leftarrow\kern-9mu\Mapsfromchar} mathrel ⤆ stmaryrd
+\def\Longmapsto{\Mapstochar\Longrightarrow} mathrel ⟾ stmaryrd
+\def\longmapsfrom{\longleftarrow\mapsfromchar} mathrel ⟻ stmaryrd
+\def\Longmapsfrom{\Longleftarrow\mathrel{\kern1mu}\Mapsfromchar} mathrel ⟽ stmaryrd