I have a Magnolia champaca plant, also known as 'Son champa' in India.
Recently a few of its leaves contained some very tiny (about 0.5-1 mm in diameter approximately) purple colored jelly kind of stuff.
It very closely resembled a turtle's hump. The slightly bigger ones had some very light purple and yellow colored uniform patterns with an even purple background. The smaller ones however were uniformly purple colored.
I am not sure if they were eggs or pests, they were leaving behind a dry dark brown bubble (holes in some cases) in the leaves they were hosted on.
I plucked off the affected leaves.
Does anybody have any idea what that was and how I can protect my plant?
After @Bamboo's answer I looked up for details about the Mangolia Scales and found the exact picture of bug + impact, adding it below, also found this site very useful - http://nassau.ifas.ufl.edu/horticulture/gardentalk/disease.html