The Ataris Pallidipennis Stal is a bug (more formally, a form of beetle) which is native to South Africa.
The reason it's in the news today is because one of them was found in a shipment of flowers from South Africa at customs in Miami. Now the idea that there's a bug or a beetle in a shipment of flowers shouldn't cause all that much excitement: however, we do have to be very careful indeed about introduced species.
That«'s what the problem is about Ataris Pallidipennis Stal, not that there's one in the country: but how many others might be coming in by the same route. And if there are others, and they manage to establish themselves, what might happen next?
Most introduced species manage to go nowhere of course. They get eaten by the first predator that likes the look of them, die from the change in climate, whatever. But those few that manage to establish themselves can cause huge problems. Rabbits are not native to Australia, they were deliberately introduced. But as they have no natural predator there they multiplied, well, like rabbits, and have stripped large areas of the country of vegetation. Cane toads are causing similar problems (they were introduced to eat an insect which was itself causing problems).
Cats arriving in New Zealand (along with rats) have virtually wiped out ground nesting birds like the Kakapo and some offshore islands have been deliberately stripped of both cats and rats to give the birds a chance. Zebra mussels are causing problems at power station water inlets and everyone should have heard the horror stories about Japanese bindweed by now.
The point isn't that one single Ataris Pallidipennis Stalhas been found it's that we are pretty sure that we only ever find a minute portion of these stowaways: so how many more of them are there out there and what sort of problems might they cause?