diff --git a/.github/workflows/upstream-dev-ci.yml b/.github/workflows/upstream-dev-ci.yml
index 50698c088..0d73a9d6a 100644
--- a/.github/workflows/upstream-dev-ci.yml
+++ b/.github/workflows/upstream-dev-ci.yml
@@ -27,7 +27,6 @@ jobs:
       - name: set up environment
         uses: mamba-org/setup-micromamba@v2
         with:
-          micromamba-version: '1.5.10-0'
           environment-file: conda_environment.yml
           create-args: >-
             python=${{ matrix.python-version }}