Turnstone

Turnstones are two bird species that constitute the genus Arenaria in the family Scolopacidae. They are closely related to calidrid sandpipers and might be considered members of the tribe Calidriini.<ref name = thomasetal2004/>

The genus Arenaria was introduced by the French zoologist Mathurin Jacques Brisson in 1760 with the ruddy turnstone (Arenaria interpres) as the type species.<ref>Template:Cite book</ref><ref>Template:Cite book</ref> The genus name arenaria is from Latin arenarius, "inhabiting sand", from arena, "sand".<ref name=job>Template:Cite book</ref>

The genus contains two species: the ruddy turnstone (Arenaria interpres) and the black turnstone (Arenaria melanocephala).<ref name=ioc>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Both birds are waders. Their length is typically between 20 and 25 cm, with a wingspan between 50 and 60 cm and a body mass between 110 and 130g. For waders their build is stocky, with short, slightly upturned, wedge shaped bills. They have white patches on the back, wings and tail. They are high Arctic breeders, and are migratory. Their strong necks and powerful, slightly upturned bills are adapted to their feeding technique. As the name implies, these species overturn stones, seaweed, and similar items in search of invertebrate prey.<ref name= "ColinsBG">Svensson, Lars et al. Collins Bird Guide 2nd ed. Publisher: Collins 2010. Template:ISBN</ref> They are strictly coastal, prefer stony beaches to sand, and often share beach space with other species of waders such as purple sandpipers.

Species

There exists a fossil bone, a distal piece of tarsometatarsus found in the Edson Beds of Sherman County, Kansas. Dating from the mid-Blancan some 4-3 million years ago, it appears to be from a calidriid somewhat similar to a pectoral sandpiper, but has some traits reminiscent of turnstones.<ref name=Wetmore/> Depending on which traits are apomorphic and plesiomorphic, it may be an ancestral representative of either lineage.

External links

• Ruddy turnstone = turnstone - Species text in The Atlas of Southern African Birds
• Ruddy turnstone – Cornell Lab of Ornithology
• Ruddy turnstone Arenaria interpres – USGS Patuxent Bird Identification InfoCenter
• Turnstones feeding and bathing