That patten is exactly what I tie and fish. The beetles here are the first significant hatch, or should I say fall, on our waters. Usually late April we get vast numbers of heather beetles. This year it is late, like everything else. I have no idea if it will happen or if we will miss out this year. The above fly in a dark tan or light brown on a size 16 is about as good an imitation you'll get. Its not brilliant but it is about the best. Its a hard hatch to crack. We are usually glad to see the back of it as that is when the best of the sport starts.
Cheers,
A.