The Christmas sandpiper or Kiritimati sandpiper (Prosobonia cancellata) was a small shorebird. It became extinct some time in the first half of the 19th century. It was endemic to Christmas Island (now also Kiritimati), since 1919 part of Kiribati. It is known solely from a single contemporaneous illustration (by William Wade Ellis), and a description by William Anderson, both made during the third circumnavigation voyage commanded by Captain James Cook, which visited the atoll of Christmas Island between 24 December 1777 and 2 January 1778.