diff --git a/ansible_mitogen/connection.py b/ansible_mitogen/connection.py
index 65091a1d..78936fd1 100644
--- a/ansible_mitogen/connection.py
+++ b/ansible_mitogen/connection.py
@@ -132,6 +132,7 @@ class Connection(ansible.plugins.connection.ConnectionBase):
                 'password': self._play_context.password,
                 'port': self._play_context.port,
                 'python_path': self.python_path,
+                'identity_file': self._play_context.private_key_file,
                 'ssh_path': self._play_context.ssh_executable,
                 'connect_timeout': self.connect_timeout,
             })
diff --git a/docs/ansible.rst b/docs/ansible.rst
index cb4a0e0b..f8c1bc26 100644
--- a/docs/ansible.rst
+++ b/docs/ansible.rst
@@ -201,7 +201,8 @@ This list will grow as more missing pieces are discovered.
 * ansible_user, ansible_ssh_user
 * ansible_port, ssh_port
 * ansible_ssh_executable, ssh_executable
-* password (default: assume passwordless)
+* ansible_ssh_private_key_file
+* ansible_ssh_pass, ansible_password (default: assume passwordless)
 
 
 Sudo Variables