You never know about those photo-bombers. You can't trust 'em.

So here I was, trying to photograph a tiny egg that a monarch butterfly had just deposited on our milkweed.

I held it up for a better look. 

And then, the photo-bomber! 

An oleander aphid, Aphis nerii, appeared out of nowhere and headed over to the egg for a quick "inspection."

Oleander aphids suck the juices, the very lifeblood, out of milkweed plants. They're yellow with black cornicles, they're non-native, and they're pests on milkweed when all you want are guests! (Like monarchs)

Want to know more about these pests? Check out the UC Statewide Integrated Pest Management Program's website on aphids.

"Aphids are small, soft-bodied insects with long slender mouthparts that they use to pierce stems, leaves, and other tender plant parts and suck out fluids," UC IPM says. "Almost every plant has one or more aphid species that occasionally feed on it."

They are also quite good at photo-bombing. Trust me.