Fly-killing climber?
 

Have others encountered this? With the approach of winter the greenhouse
windows are now being closed at night. I entered mine this morning to
open the windows and was very surprised at the sight on my 'Thunbergia
coccinea var. lutea' climber as was covered with dozens of common house
flies that had died on the leaves. No chemicals are used. My initial
impression was they had dropped exhausted from the glazing above but
this had not happened. The corpses are at all angles on the vertical
leaves as though they had begun drawing nutrient from the leaf and
promptly curled their toes up!