diff --git a/zdefs.acs b/zdefs.acs
index 68acc1b..8097c78 100644
--- a/zdefs.acs
+++ b/zdefs.acs
@@ -244,6 +244,7 @@
 #define APROP_SpawnHealth	17
 #define APROP_Dropped		18
 #define APROP_Notarget		19
+#define APROP_Species		20
 
 // Render Styles ------------------------------------------------------------