diff --git a/crates/tor-keymgr/src/key_type/ssh.rs b/crates/tor-keymgr/src/key_type/ssh.rs
index ac0d1b27c..f80b9b868 100644
--- a/crates/tor-keymgr/src/key_type/ssh.rs
+++ b/crates/tor-keymgr/src/key_type/ssh.rs
@@ -241,6 +241,9 @@ mod tests {
     const OPENSSH_ED25519: &[u8] = include_bytes!("../../testdata/ed25519_openssh.private");
     const OPENSSH_ED25519_BAD: &[u8] = include_bytes!("../../testdata/ed25519_openssh_bad.private");
     const OPENSSH_DSA: &[u8] = include_bytes!("../../testdata/dsa_openssh.private");
+    const OPENSSH_X25519: &[u8] = include_bytes!("../../testdata/x25519_openssh.private");
+    const OPENSSH_X25519_UNKNOWN_ALGORITHM: &[u8] =
+        include_bytes!("../../testdata/x25519_openssh_unknown_algorithm.private");
 
     #[test]
     fn wrong_key_type() {
@@ -284,4 +287,31 @@ mod tests {
 
         assert!(erased_key.downcast::<ed25519::Keypair>().is_ok());
     }
+
+    #[test]
+    fn x25519_key() {
+        let key_type = KeyType::X25519StaticSecret;
+        let key = UnparsedOpenSshKey::new(OPENSSH_X25519.into(), PathBuf::from("/dummy/path"));
+        let erased_key = key_type.parse_ssh_format_erased(key).unwrap();
+
+        assert!(erased_key.downcast::<curve25519::StaticSecret>().is_ok());
+    }
+
+    #[test]
+    fn invalid_x25519_key() {
+        let key_type = KeyType::X25519StaticSecret;
+        let key = UnparsedOpenSshKey::new(
+            OPENSSH_X25519_UNKNOWN_ALGORITHM.into(),
+            PathBuf::from("/dummy/path"),
+        );
+        let err = key_type
+            .parse_ssh_format_erased(key)
+            .map(|_| "<type erased key>")
+            .unwrap_err();
+
+        assert_eq!(
+            err.to_string(),
+            "Unexpected OpenSSH key type: wanted X25519, found pangolin@torproject.org"
+        );
+    }
 }
diff --git a/crates/tor-keymgr/testdata/x25519_openssh.private b/crates/tor-keymgr/testdata/x25519_openssh.private
new file mode 100644
index 000000000..33552585f
--- /dev/null
+++ b/crates/tor-keymgr/testdata/x25519_openssh.private
@@ -0,0 +1,7 @@
+-----BEGIN OPENSSH PRIVATE KEY-----
+b3BlbnNzaC1rZXktdjEAAAAABG5vbmUAAAAEbm9uZQAAAAAAAAABAAAAPQAAABV4MjU1MT
+lAdG9ycHJvamVjdC5vcmcAAAAgD3MDTeSLGUGD1Re2s6aF6g73KSyiteXjV1SL+pu6ASUA
+AAB4wA/uXMAP7lwAAAAVeDI1NTE5QHRvcnByb2plY3Qub3JnAAAAIA9zA03kixlBg9UXtr
+OmheoO9yksorXl41dUi/qbugElAAAAIDCADBQ5fbboMIMbmOgHMfHZEaIcdm0TF2Kt8bHc
+pz5zAAAACHRlc3Qta2V5AQID
+-----END OPENSSH PRIVATE KEY-----
diff --git a/crates/tor-keymgr/testdata/x25519_openssh_unknown_algorithm.private b/crates/tor-keymgr/testdata/x25519_openssh_unknown_algorithm.private
new file mode 100644
index 000000000..a048a9b70
--- /dev/null
+++ b/crates/tor-keymgr/testdata/x25519_openssh_unknown_algorithm.private
@@ -0,0 +1,7 @@
+-----BEGIN OPENSSH PRIVATE KEY-----
+b3BlbnNzaC1rZXktdjEAAAAABG5vbmUAAAAEbm9uZQAAAAAAAAABAAAAPwAAABdwYW5nb2
+xpbkB0b3Jwcm9qZWN0Lm9yZwAAACBFTBevfAXZy6Ut6i9PSHeXHUpaJ6+NKabGzeoT6rFV
+DgAAAHjiJEYk4iRGJAAAABdwYW5nb2xpbkB0b3Jwcm9qZWN0Lm9yZwAAACBFTBevfAXZy6
+Ut6i9PSHeXHUpaJ6+NKabGzeoT6rFVDgAAACBo1W5vk9S8KAG7icAnKfq0NasfGTLO2+MJ
+ifSnMVvXSgAAAAh0ZXN0LWtleQE=
+-----END OPENSSH PRIVATE KEY-----