diff --git a/R/prj_vtkdiff.R b/R/prj_vtkdiff.R
index e0af0d5f73e34b50c8b4decee775d8b6f6965fae..5c443e5f2b86a207302132d1c0a3c6ea0c3854af 100644
--- a/R/prj_vtkdiff.R
+++ b/R/prj_vtkdiff.R
@@ -40,7 +40,6 @@ new_r2ogs6_vtkdiff <- function(regex,
              field = field,
              absolute_tolerance = absolute_tolerance,
              relative_tolerance = relative_tolerance,
-             tag_name = "vtkdiff",
              is_subclass = FALSE,
              attr_names = character(),
              flatten_on_exp = character()