Messerschmitt Bf.109B/C/D - Spanish Civil War, part two

The Bf.109D reverted to the Junkers Jumo 210D engine had additional wing guns and a new tailwheel. Apparently the German intelligence services launched the idea that it was powered by a Daimler-Benz DB.600 engine in the Zürich Air Show of 1937, however, even if initially it was planned to be fitted with it, the shortage of them forced Messerschmitt to switch to the Junkers Jumo.
Many of them of every sub-variant, including the Bf.109E were sent to Spain to be combat tested with the Condor Legion where they faced Soviet-made fighters from early-to-mid 1937 onwards. They quickly replaced the Heinkel He.51 biplane that suffered many casualties during the first 12 months of the war as it proved to be the best fighter the Nationalists could handle as they weren't match for the main Republican fighter, the Soviet-built Polikarpov I-15 and I-16 and they lost many aircraft to Condor Legion pilots and ground anti-air fire.
After the Spanish Civil War, many of them served with the Spanish Ejército del Aire (Army of the Air) assigned to first line duties in the Pyrenees sector until 1944 when they were withdrawn from the first line and assigned to trainer duties and moved to Southern military flying schools.
It's worth to point that back during the Spanish Civil War, a second Bf.109 was captured by the Republicans (the first one was one of the prototypes). On 6th December 1937 a Bf.109B forced landed on a road close to Guadalajara (North of Madrid), controlled by the Republicans as it ran out of fuel. It was sent to Sabadell, in Catalonia to be tested by the Republicans first and French pilots later and then, it was repainted and sent to the USSR by ship. Its fate in the USSR is unknown but most likely it was tested time after time and the scrapped.

Sources:
1. https://en.wikipedia.org/wiki/Messerschmitt_Bf_109_operational_history#Combat_service_in_the_Spanish_Civil_War
2. http://bioold.science.ku.dk/drnash/model/spain/bf109.html
3. http://www.network54.com/Forum/394728/thread/1181682653/Messerschmitt+Bf+109+B+republicano... (translated)
4. http://niehorster.org/080_spain/__spain.html
5. Salamander Books - The Complete Book of Fighters
6. Signal Squadron - Aircraft In action 44 - Messerschmitt Bf-109 in Action Pt.1