diff --git a/tornado/platform/asyncio.py b/tornado/platform/asyncio.py
index b7b63d199..f7626c53b 100644
--- a/tornado/platform/asyncio.py
+++ b/tornado/platform/asyncio.py
@@ -53,6 +53,9 @@ class _HasFileno(Protocol):
     def fileno(self) -> int:
         pass
 
+    def __hash__(self) -> int:
+        pass
+
 
 _FileDescriptorLike = Union[int, _HasFileno]
 
@@ -727,7 +730,7 @@ def close(self) -> None:
 
     def add_reader(
         self,
-        fd: "_FileDescriptorLike",
+        fd: "_FileDescriptorLike",  # type: ignore[override]
         callback: Callable[..., None],
         *args: "Unpack[_Ts]",
     ) -> None:
@@ -735,14 +738,14 @@ def add_reader(
 
     def add_writer(
         self,
-        fd: "_FileDescriptorLike",
+        fd: "_FileDescriptorLike",  # type: ignore[override]
         callback: Callable[..., None],
         *args: "Unpack[_Ts]",
     ) -> None:
         return self._selector.add_writer(fd, callback, *args)
 
-    def remove_reader(self, fd: "_FileDescriptorLike") -> bool:
+    def remove_reader(self, fd: "_FileDescriptorLike") -> bool:  # type: ignore[override]
         return self._selector.remove_reader(fd)
 
-    def remove_writer(self, fd: "_FileDescriptorLike") -> bool:
+    def remove_writer(self, fd: "_FileDescriptorLike") -> bool:  # type: ignore[override]
         return self._selector.remove_writer(fd)