This is probably I-ALAN, used for regular flights between Italy and Brazil, mostly for mail. In May-June 1940 it was impressed in military service, still in civil markings, for flights in the Mediterranean area and to Abyssinia. On July 16 1940, en route to Abyssinia, it aborted take off at Benghazi and the undercarriage collapsed. British troops found the wreck in February 1941.
For the pictures of I-ALAN below, I acknowledge
http://www.ams.vr.it/Documents/Sm.79%20drawpro/Sm.79%20drawpro.htm
Also, in the panoramic picture of the SM79T, note on the extreme left a Breda Ba65, in centre background an SM81 Pipistrello, with an MC200 fuselage in front of it, extreme right another SM81, or possibly its airliner origin the SM73, and the wingtip of another probable SM81 in centre foreground.
I thank Carlo Soliani for this history and help with identification.