within 2 days, the leafs on my tomato plants have been eaten down to the stems. there are hundreds of bugs that that look like a lighting bug, but aren't. they are leaving little black droppings on the tomatoes, kind of like mouse dropping and on the ground to where the ground looks black. they have yellow stripes on their backs. Can you or someone help me figure out what kind of bugs are killing my tomato plants. there are no worms on them, just these bugs which have totally stripped my plants of leaves.

Martha