Ficus elastica (robusta): what larva are these, and what is this white buildup?

Question

my ficus has been doing well and growing well over the past 3 years. But recently two things have started happening:

New leaves all become yellow and mushy, and sticky strings are sticking out of them (like residue from a hot glue gun). When I open a new leaf, it often contains small larvae (see picture). However, I can't find what kind of larvae they are. Do you know what larvae these are? I read that it would be a good idea to rub the leaves with some soapy water to get rid of them, but does that also apply for these?
The older leaves have started to form blobs composed of many small white specks (see bottom left of pic). They are mostly the lower, older leaves. Do you know what these are? Do they indicate illness? What can I do to make my ficus healthier again?

kevinskio · Answer

This looks like thrip to me.  More details are included in a previous answer here.
When I was doing interior landscaping if a plant got thrip the most effective solution was to dispose of it as fast as possible.  This was the best solution for these reasons:

the adults fly when disturbed and can feed on a wide range of plants
the larvae live inside the leaf and are not controlled by the usual contact insecticides such as soap or diazinon or neem oil.
systemic insecticides which are absorbed by the plant are not usually available to homeowner

Ficus elastica (robusta): what larva are these, and what is this white buildup?

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