[Meta menardi]

It is Araneus quadratus, heavily gravid. Pretty soon she will produce large numbers of eggs, the shape of the abdomen will change to a much smaller size (surprise!) and change colour. The paleness is partly due to distension of the chromatophores, as they become more compact the colour will change. I had one a couple of years ago that was slightly darker than the one shown here, after she had dropped her eggs the body became a dark red.