These red marks on the ankle of a holidaymaker are sandfly bites. Sandflies are small blackflies (Austrosimulium species). Only the adult female bites, and as she does she injects an anticoagulant into the blood vessels to prevent the blood from clotting. This also causes a severe itching to develop in the surrounding skin.
Te whakamahi i tēnei tūemi
© Copyright image. All rights reserved. Permission from Manaaki Whenua: Landcare Research New Zealand Limited must be obtained before the re-use of this image.