diff --git a/pkgs/by-name/ar/arpack/package.nix b/pkgs/by-name/ar/arpack/package.nix
index 4e059b3ea95c..492d5fea1b21 100644
--- a/pkgs/by-name/ar/arpack/package.nix
+++ b/pkgs/by-name/ar/arpack/package.nix
@@ -13,7 +13,7 @@ assert useMpi -> !blas.isILP64;
 assert useAccel -> stdenv.hostPlatform.isDarwin;
 
 stdenv.mkDerivation rec {
-  pname = "arpack";
+  pname = "arpack${lib.optionalString useMpi "-mpi"}";
   version = "3.9.1";
 
   src = fetchFromGitHub {