Tringa is a
genus of
waders, containing the shanks and tattlers. The genus name Tringa is the
Neo-Latin name given to the
green sandpiper by the Italian naturalist
Ulisse Aldrovandi in 1599. They are mainly freshwater birds, often with brightly coloured legs as reflected in the English names of six species, as well as the
specific names of two of these and the
green sandpiper. They are typically associated with northern hemisphere temperate regions for breeding. Some of this group—notably the green sandpiper—nest in trees, using the old nests of other birds, usually
thrushes.
The
willet and the tattlers have been found to belong in Tringa; these genus changes were formally adopted by the
American Ornithologists' Union in 2006.[1]
The present genus in the old, more limited sense was even further subdivided into Tringa proper and Totanus, either as
subgenera or as full genera. The available
DNA sequence data suggests however that neither of these is
monophyletic and that the latter simply lumps together a number of more or less closely related
apomorphic species. Therefore, it seems unwarranted to recognize Totanus even as a subgenus for the time being.[2]
The shanks' and tattlers' closest relatives are
sandpipers of the genera Actitis and Xenus. Together with these, they are related to the
phalaropes, as well as the
turnstones and
calidrids.[8] The large
genusTringa and the two very small genera which are most closely related form a
phylogeny similar to the situation found in many other shorebird lineages such as
calidrids,
snipes and
woodcocks, or
gulls.
The same study[8] has indicated that some
morphological characters such as details of the
furcula and
pelvis have evolved
convergently and are no indicators of close relationship. Similarly, the leg/foot color wildly varies between close relatives, with the
spotted redshank, the
greater yellowlegs, and the
common greenshank for example being more closely related among each other than to any other species in the group; the ancestral coloration of the legs and feet was fairly certainly drab buffish as in e.g. the
green sandpiper. On the other hand, the molecular
phylogeny reveals that the general habitus and size as well as the overall plumage pattern are good indicators of an evolutionary relationship in this group.
The
Nordmann's greenshank, a rare and
endangered species, was not available for molecular analyses. It is fairly aberrant and was formerly placed in the
monotypic genus Pseudototanus. It appears closest overall to the semipalmata-flavipes and the stagnatilis-totanus-glareola groups, though it also has some similarities to the
greater yellowlegs and
common greenshank.
Fossil shanks are known since the
Miocene, possibly even since the
Eo-/
Oligocene some 33-30
million years ago (mya) which would be far earlier than most extant genera of birds. However, it is uncertain whether Tringa edwardsi indeed belongs into the present-day genus or is a distinct, ancestral form. The time of the Tringa-Actitis-Xenus-Phalaropus divergence has been tentatively dated at 22 mya, the beginning of the Miocene;[10] even if the dating is largely conjectural, it suggests that T. edwardsi does indeed not belong into the modern genus. Molecular dating[11]—which is not too reliable, however—indicates that the diversification into the known lineages occurred between 20 and 5 mya. The fossil record contains species formerly separated in Totanus from the Early Miocene onwards. Although these are usually known from very scant remains, the fact that apparently
apomorphicTringa as well as a putative phalarope are known from about 23-22 mya indicates that the shank-phalarope group had already diverged into the modern genera by the start of the Miocene. The
biogeography of living and fossil species—notably, the rarity of the latter in well-researched
North American sites—seems to suggest that Tringa originated in Eurasia. Time and place neatly coincide with the disappearance of the last vestiges of the
Turgai Sea, and this process may well have been a major factor in the separation of the genera in the shank-phalarope
clade. Still, scolopacids are very similar osteologically, and many of the early fossils of presumed shanks require revaluation.[9]
?Tringa edwardsi (Quercy Late Eocene/Early Oligocene of Mouillac, France)
?Tringa gracilis (Early Miocene of WC Europe) –
calidrid?
?Tringa lartetianus (Early Miocene of Saint-Gérand-le-Puy, France)
Tringa spp. (Early Miocene of Ravolzhausen, Germany – Early Pleistocene of Europe)[12]
?Tringa grivensis (Middle Miocene of Grive-Saint-Alban, France)
?Tringa majori (Middle Miocene of Grive-Saint-Alban, France)
?Tringa minor (Middle Miocene of Grive-Saint-Alban, France) – includes "Erolia" ennouchii; calidriid?
?Tringa grigorescui (Middle Miocene of Ciobăniţa, Romania)
?Tringa scarabellii (Late Miocene of Senigallia, Italy)
Tringa sp. 1 (Late Miocene/Early Pliocene of Lee Creek Mine, USA)
Tringa sp. 2 (Late Miocene/Early Pliocene of Lee Creek Mine, USA)
?Tringa numenioides (Early Pliocene of Odesa, Ukraine)
Tringa antiqua (Late Pliocene of Meade County, USA)
Tringa ameghini (Late Pleistocene of Talara Tar Seeps, Peru)
"Tringa" hoffmanni is now in Ludiortyx. While its relationships are disputed, it was not a charadriiform.
Ballmann, Peter (1969): Les Oiseaux miocènes de la Grive-Saint-Alban (Isère) [The Miocene birds of Grive-Saint-Alban (Isère)]. Geobios2: 157–204. [French with English abstract]
doi:
10.1016/S0016-6995(69)80005-7