Little monsters on my tomatoes. What are they?

AMamani
by AMamani
I have these tiny little creatures on my cherry tomato plants. What are they? They seem to stay in one place on the stem if I don't mess with them, and they don't seem to do much damage to the plant (none at all to the fruit). Should I worry about them?
They are usually in bunches like this and have attracted ants to tend them.
The drier part above is the damage left after I scraped a bunch off last week.
  3 answers
  • Gonfshn77302 Gonfshn77302 on Apr 22, 2015
    Look like lil spiky aphids to me. Neem Oil works well. Some swear by a blast from a water hose but that seems counter productive if their demise is hoped for. A mix of dish soap and water sprayed is said to work well too.Only good aphid is a dead aphid. Haha
  • Francine Nault Francine Nault on Apr 23, 2015
    I was once told that you can't prevent these by spraying your plan with a solution you actually have to spray the bug itself.
    • AMamani AMamani on Apr 23, 2015
      @Francine Nault That is true. I use the leftover soapy water after doing laundry to spray the little green aphids that sometimes show up on my roses. Aphids have oily skin and the soap removes that oil and causes them to actually dry up! Contact has to be made with the bug itself, but they are good and dead by the next day.
  • AMamani AMamani on Apr 23, 2015
    Figured it out! They are the nymph stage of Keeled Treehoppers. I found one of the big green mature bugs near the mob and when I searched for it online the whole group made sense. This website http://blog.hmns.org/tag/keeled-treehopper/ has a great photo of mature and nymphs together as well as some good info if anybody else needs it.