Calidrid
| Typical waders | |
|---|---|
 |
|
|
Red knot, Calidris canutus. Calidris s.str. are stout birds with bold pattern in breeding plumage |
|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Charadriiformes |
| Family: | Scolopacidae (partim) |
| Genera | |
|
Calidris |
|
Calidris
and see text.
The calidrids or typical waders are a group of Arctic-breeding, strongly migratory wading birds. These birds form huge mixed flocks on coasts and estuaries in winter. They are the typical "sandpipers", small to medium-sized, long-winged and relatively short-billed.
Their bills have sensitive tips which contain numerous Corpuscles of Herbst. This enables the birds to locate buried prey items, which they typically seek with restless running and probing.
As the common name "sandpiper" is shared by some calidrids with more distantly related birds such as the Actitis species, the term stint is preferred in Britain for the smaller species of this group.
The calidrids' closest relatives are the two species of turnstone, and if the calidrids were to be considered one or two tribes Calidriini and/or Arenariini, and/or subfamily Eroliinae, the turnstones would be included in it. 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. Depending on which traits are apomorphic and plesiomorphic, it may be an ancestral representative of either lineage. It might also belong to some distinct prehistoric genus, as true calidriid sandpipers seem to have been present earlier (see below).
...
Wikipedia