Kingdom: Animalia
Phylum: Chordata
Class: Aves
Subclass: Neornithes
Infraclass: Neognathae
Superorder: Neoaves
Order: Charadriiformes
Suborder: Scolopaci
Family: Scolopacidae
Genus: Xenus
Species: X. cinereus
Binomial name Xenus cinereus
Synonyms: Tringa cinerea, Tringa terek
Common names: Terek sandpiper

The Xenus cinereus (Terek sandpiper) is a rare small long-distance migratory Palearctic wader species, the only member of the genus Xenus. This bird breeds near water in the taiga from Finland through northern Siberia to the Kolyma River, and migrate south in winter to tropical coasts in East Africa, South Asia and Australia with a few stragglers coming to New Zealand inhabiting mudflats and estuaries. Some years they do not arrive. They have been recorded from Northland to Southland, usually among flocks of wrybills or other small waders. 
It is a small wader with short yellow-orange legs and a long black bill that is upturned. The bird’s upperparts are a brown-grey, the underparts white, and a thin white trailing edge that shows on the upper wing during flight. It has a body length of 25cm (bill tip to tail). 
Terek sandpiper feeds by probing deeply for polychaete worms, molluscs and crustaceans with its long bill. They also chase insects and other mobile prey and sometimes run to the water's edge to wash the catch.

Xenus cinereus by Alnus.jpg 

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