Tiny black spots on blue morning glory plant

Question

Does anyone know what these tiny black spots on the leaves of my morning glory plants are?

It seems that the spots are only on the top of the leaf, not under. I also saw a couple on a petiole. I was able to wash the specks off with soapy water. I can also remove the specks with a toothpick, but otherwise they're hard to remove (they don't brush off).

After I washed the specks off, I saw some silvery, maybe translucent, patches on the leaves.

I just saw a small, roundish black bug fly off of a leaf today, but this was my first time seeing any bug. After checking carefully under each leaf, I did not find any more bugs. However, I noticed a few small holes in some leaves.

It's an indoor potted plant and I mostly use an indoor plant light. I cut off the leaves with specks, in case it's a fungus. Then I sprayed each leaf with a mixture of eucalyptus oil and water - no idea if it will work, but that's all I have right now. If anyone knows what the specks are or has suggestions to share, I'd really appreciate it!

Answer 1

This looks like thrip to me. The indications are long thin looping trails where the larvae are eating inside the leaf and small black spots of "frass" or poop. Adult thrip can often be seen under the leaf and they are the size of an exclamation mark. Thrip cannot be effectively controlled by soap and water or any contact insecticide as the larvae live inside the leaf. As the adults can fly to new plants and infect them I recommend getting rid of the plant before you get more problems.