diff --git a/module/ice-9/boot-9.scm b/module/ice-9/boot-9.scm
index 3cd3bdc12..19c22eabb 100644
--- a/module/ice-9/boot-9.scm
+++ b/module/ice-9/boot-9.scm
@@ -4161,6 +4161,8 @@ when none is available, reading FILE-NAME with READER."
                          (lambda (formals ...)
                            body ...))
                        args ...))
+                   ((_ a (... ...))
+                    (syntax-violation 'name "Wrong number of arguments" x))
                    (_
                     (identifier? x)
                     #'proc-name))))))))))
diff --git a/module/srfi/srfi-9.scm b/module/srfi/srfi-9.scm
index d213a8656..2fc892865 100644
--- a/module/srfi/srfi-9.scm
+++ b/module/srfi/srfi-9.scm
@@ -122,6 +122,8 @@
                     #'((lambda (formals ...)
                          body ...)
                        args ...))
+                   ((_ a (... ...))
+                    (syntax-violation 'name "Wrong number of arguments" x))
                    (_
                     (identifier? x)
                     #'proc-name))))))))))