Arduino IDE: "serial port not found" when uploading. Serial monitor works fine.

I'm having trouble uploading my code from the Arduino IDE on my desktop Mac to my Artemis board. I use the CH34x_V1.5 USB-Serial driver. The serial terminal window in the Arduino IDE talks to the Artemis board, but whenever push the upload button I get the following error in the console:

Error loading Python lib '/var/folders/4_/cj5947n15sj49fm374z3yrtw0000gp/T/MEItc3kVK/Python': dlopen: dlopen(/var/folders/4/cj5947n15sj49fm374z3yrtw0000gp/T/_MEItc3kVK/Python, 10): Symbol not found: clock_getres
Referenced from: /var/folders/4
/cj5947n15sj49fm374z3yrtw0000gp/T/MEItc3kVK/Python
Expected in: /usr/lib/libSystem.B.dylib
in /var/folders/4
/cj5947n15sj49fm374z3yrtw0000gp/T/MEItc3kVK/Python
the selected serial port in /var/folders/4
/cj5947n15sj49fm374z3yrtw0000gp/T/_MEItc3kVK/Python
does not exist or your board is not connected

I can upload from my Macbook, and the Arduino IDE version and configuration appear to be identical. Except my MacBook identifies the port as cu.wchusbserial1140 and my desktop Mac as cu.wchusbserialfd330. I believe ran the same CH34x driver installer on both machines.

Is there a serial port configuration or Python configuration on my desktop Mac I should look for?
Thanks