diff --git a/var/spack/repos/builtin/packages/py-arrow/package.py b/var/spack/repos/builtin/packages/py-arrow/package.py
index d307e6bbb3c5ca514b80ccf618c80b6ef003b3d4..acc42ea77762f3aa7c99acf48035bd3bf8b899a4 100644
--- a/var/spack/repos/builtin/packages/py-arrow/package.py
+++ b/var/spack/repos/builtin/packages/py-arrow/package.py
@@ -21,7 +21,7 @@ class PyArrow(PythonPackage):
 
     depends_on('python@2.7:2.8,3.5:', type=('build', 'run'))
     depends_on('py-setuptools', type='build')
-    depends_on('py-backports-functools_lru_cache@1.2.1:', type=('build', 'run'), when='^python@2.7:2.8')
+    depends_on('py-backports-functools-lru-cache@1.2.1:', type=('build', 'run'), when='^python@2.7:2.8')
     depends_on('py-python-dateutil', type=('build', 'run'))
     depends_on('py-chai', type='test')
     depends_on('py-mock', type='test')