diff --git a/.github/PULL_REQUEST_TEMPLATE.md b/.github/PULL_REQUEST_TEMPLATE.md
index 14b75d86f5a..0c259cf5672 100644
--- a/.github/PULL_REQUEST_TEMPLATE.md
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@@ -20,7 +20,6 @@ Fixes #
 - [ ] Write detailed docstrings for all functions/methods.
 - [ ] If wrapping a new module, open a 'Wrap new GMT module' issue and submit reasonably-sized PRs.
 - [ ] If adding new functionality, add an example to docstrings or tutorials.
-- [ ] Use underscores (not hyphens) in names of Python files and directories.
 
 **Slash Commands**
 
diff --git a/.github/workflows/style_checks.yaml b/.github/workflows/style_checks.yaml
index f15bcde0012..43fa5acd6c7 100644
--- a/.github/workflows/style_checks.yaml
+++ b/.github/workflows/style_checks.yaml
@@ -52,3 +52,15 @@ jobs:
             rm output.txt
             exit $nfiles
           fi
+
+      - name: Ensure hyphens are not used in names of directories and Python files
+        run: |
+          git ls-files '*.py' | grep '-' > output.txt || true
+          git ls-tree -rd --name-only HEAD | grep '-' >> output.txt || true
+          nfiles=$(wc --lines output.txt | awk '{print $1}')
+          if [[ $nfiles > 0 ]]; then
+            echo "Following directories/files use hyphens in file names:"
+            cat output.txt
+            rm output.txt
+            exit $nfiles
+          fi
diff --git a/doc/contributing.md b/doc/contributing.md
index 5dd93418f53..36b0d76e984 100644
--- a/doc/contributing.md
+++ b/doc/contributing.md
@@ -130,9 +130,9 @@ our tests. This way, the *main* branch is always stable.
     integrated separately.
   - Bug fixes should be submitted in separate PRs.
 * How to write and submit a PR
-  - Use underscores for all Python (*.py) files as per
-    [PEP8](https://www.python.org/dev/peps/pep-0008/), not hyphens. Directory
-    names should also use underscores instead of hyphens.
+  - Use underscores for all Python (\*.py) files as per
+    [PEP8](https://www.python.org/dev/peps/pep-0008/), not hyphens. Directory names
+    should also use underscores instead of hyphens.
   - Describe what your PR changes and *why* this is a good thing. Be as
     specific as you can. The PR description is how we keep track of the changes
     made to the project over time.