diff --git a/src_main/io_devices/piserial.cpp b/src_main/io_devices/piserial.cpp
index 158cb4ab..514309aa 100755
--- a/src_main/io_devices/piserial.cpp
+++ b/src_main/io_devices/piserial.cpp
@@ -821,6 +821,10 @@ PIStringList PISerial::availableDevices(bool test) {
 			<< "ttyMI" << "ttymxc" << "ttyAMA" << "rfcomm" << "ircomm";
 #      ifdef FREE_BSD
 	prefixes << "cu";
+#      endif
+#      ifdef APPLE
+	prefixes.clear();
+	prefixes << "cu." << "tty.";
 #      endif
 	PIFile file_prefixes("/proc/tty/drivers", PIIODevice::ReadOnly);
 	if (file_prefixes.open()) {