Aphids hoverflies (adults and maggots) on buds and flowers. (A) A hoverfly on a flower transporting the pollinaria on its dorsal thorax (arrow indicates position of pollinia). (B) Hoverfly carrying pollinia while laying an egg on a flower (arrow indicates the egg). (C) Aphids on inflorescences flowering in March (arrows indicate aphids and a hoverfly egg). (D) A second instar maggot preying on aphids on a flower (arrows indicate hoverfly instar and anther cap). Scale interpretation: A and B, average length of hoverfly = 9–10 mm; C, average length of aphids = 1 mm; D, average length of anther cap = 3 mm.