diff --git a/workflow/envs/cutadapt.yaml b/workflow/envs/cutadapt.yaml
index 3c011ebfbcbfc393cb62623a3abd7875903f6fa4..064d30234ed4b627aae8805b3d854b937480a926 100644
--- a/workflow/envs/cutadapt.yaml
+++ b/workflow/envs/cutadapt.yaml
@@ -3,5 +3,5 @@ channels:
   - conda-forge
   - bioconda
 dependencies:
-  - cutadapt:3.4
+  - cutadapt=3.4
 ...