I don't understand why the answer could not be singular 'millipede'?
it's less likely that the speaker is bothered by one specific millipede, or is fine with many millipedes but takes issue with just one. Going with context, the best answer is 'millipedes'
eh...i don't know...there is a millipede over on the table and I don't like it.
Specificity is in the context, and in the question as asked, there is NO context. sipendi jongoo. sipendi jongoo wadogo - on the other hand provides some context...otherwise the singular is equally accurate....unless I'm missing something?