diff --git a/utilities.py b/utilities.py
index 102c2e2e07e697c9779c335650c93858dabc5be2..8267d423b50bac8878bdc911f211f2149fbc9af5 100755
--- a/utilities.py
+++ b/utilities.py
@@ -176,7 +176,7 @@ def get_unique_species_dict_list(sp_dict_list):
 
     for sp in sp_dict_list:
         gspecies = get_gspecies_string_from_sp_dict(sp)
-        if gspecies not in unique_species_dict.keys() or sp["description"]["main_species"] == "yes" :
+        if gspecies not in unique_species_dict.keys() or sp["description"]["main_species"] :
             unique_species_dict[gspecies] = sp
         else:
             continue