diff --git sites/all/modules/panels/panels.module sites/all/modules/panels/panels.module
index ad0cb70..5577057 100644
--- sites/all/modules/panels/panels.module
+++ sites/all/modules/panels/panels.module
@@ -1243,7 +1243,7 @@ function template_preprocess_panels_pane(&$vars) {
 
   // Add template file suggestion for content type and sub-type.
   $vars['theme_hook_suggestions'][] = $base . $delimiter . $content->type;
-  $vars['theme_hook_suggestions'][] = $base . $delimiter . $content->type . $delimiter . $content->subtype;
+  $vars['theme_hook_suggestions'][] = $base . $delimiter . $content->type . $delimiter . strtr($content->subtype, '-', '_');
 
   $vars['pane_prefix'] = !empty($content->pane_prefix) ? $content->pane_prefix : '';
   $vars['pane_suffix'] = !empty($content->pane_suffix) ? $content->pane_suffix : '';