diff --git a/minigrida/descriptors/aps.py b/minigrida/descriptors/aps.py
index d66bb68..add63f8 100644
--- a/minigrida/descriptors/aps.py
+++ b/minigrida/descriptors/aps.py
@@ -54,6 +54,5 @@ def run(gt, rasters, coords, remove, attributes, adjacency='4', filtering='direc
     X = np.concatenate(X)
     y = np.concatenate(y)
     groups = np.concatenate(groups)
-    Xn = rasters[0].keys()
 
     return X, y, groups, Xn
diff --git a/minigrida/descriptors/max_aps.py b/minigrida/descriptors/max_aps.py
index 0a3c932..b7b9a00 100644
--- a/minigrida/descriptors/max_aps.py
+++ b/minigrida/descriptors/max_aps.py
@@ -58,6 +58,5 @@ def run(gt, rasters, coords, remove, attributes, adjacency='4',
     X = np.concatenate(X)
     y = np.concatenate(y)
     groups = np.concatenate(groups)
-    Xn = rasters[0].keys()
 
     return X, y, groups, Xn
diff --git a/minigrida/descriptors/sdaps.py b/minigrida/descriptors/sdaps.py
index 1e588d6..2723422 100644
--- a/minigrida/descriptors/sdaps.py
+++ b/minigrida/descriptors/sdaps.py
@@ -54,6 +54,5 @@ def run(gt, rasters, coords, remove, attributes, adjacency='4', filtering='direc
     X = np.concatenate(X)
     y = np.concatenate(y)
     groups = np.concatenate(groups)
-    Xn = rasters[0].keys()
 
     return X, y, groups, Xn