diff --git a/includes/iso.inc b/includes/iso.inc
index a88de57..06fe1fd 100644
--- a/includes/iso.inc
+++ b/includes/iso.inc
@@ -461,6 +461,7 @@ function _locale_get_predefined_list() {
     'tt' => array('Tatar', 'Tatarça'),
     'tw' => array('Twi'),
     'ty' => array('Tahitian'),
+    'tyv' => array('Tuvan', 'Тыва дыл'),
     'ug' => array('Uighur'),
     'uk' => array('Ukrainian', 'Українська'),
     'ur' => array('Urdu', /* Left-to-right marker "‭" */ 'اردو', LANGUAGE_RTL),