diff --git a/zerver/decorator.py b/zerver/decorator.py
index e7efddbbf1..5344881d89 100644
--- a/zerver/decorator.py
+++ b/zerver/decorator.py
@@ -169,8 +169,13 @@ def authenticated_api_view(view_func):
     @require_post
     @has_request_variables
     @wraps(view_func)
-    def _wrapped_view_func(request, email=REQ, api_key=REQ('api-key'),
+    def _wrapped_view_func(request, email=REQ, api_key=REQ('api_key', default=None),
+                           api_key_legacy=REQ('api-key', default=None),
                            *args, **kwargs):
+        if not api_key and not api_key_legacy:
+            raise RequestVariableMissingError("api_key")
+        elif not api_key:
+            api_key = api_key_legacy
         user_profile = validate_api_key(email, api_key)
         request.user = user_profile
         request._email = user_profile.email