Compound eye close-up of a common horsefly Haematopota pluvialis eye. Haematopa pluvialis is a small to medium-sized tabanid with a body length of 8-10 mm. The female Haematopota pluvialis has distinctively patterned hairy eyes - the eye stripes extend over most of the eye. Microscopic contrast technique : Incident brightfield. Magnification 180x when printed 10 centimetres wide.