Those asparagus beetles come in two colour schemes, one predominantly black like Lindsaylew's picture, the other red with stripes but the same size & shape. I bash them off with a finger-thumb flick and that seems to do the job. The eggs are REALLY tiny, less than a mm long and thin as a hair. If there are many I just pinch off the parts of the fern they're on.
"There are two kinds of people in the world - those who think there are two kinds of people in the world, and those who do not" - Robert Benchley