| Phoeniconaias siamensis | |
|---|---|
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Phoenicopteriformes |
| Family: | Phoenicopteridae |
| Genus: | Phoeniconaias |
| Species: | †P. siamensis |
| Binomial name | |
| †Phoeniconaias siamensis Chenevalet al., 1991 | |
Phoeniconaias siamensis is an extinct species offlamingo that lived in northernThailand during theMiocene period. Its closest living relative is thelesser flamingo.
Phoeniconaias siamensis was named in 1991 on the basis of various postcranial material found at the Mae Long Reservoir inLi, northern Thailand. Theholotype, TLi 7, is the distal end of a righttarsometatarsus, but the referred material also includes elements of both the right and left wings and hindlimbs, ascapula and acervical vertebra.
The name derives from Siam, the historical name of Thailand.[1]
One of the main ways to differentiate the three known flamingo genera is through the shape of the beak and the anatomy of the first toe bone, two features not preserved inPhoeniconaias siamensis. However the Li fossils could be referred to the genusPhoeniconaias based on the anatomy of the trochlea of thetarsometatarsus. The trochlea corresponding with the second toe shows an inner face that is elongated and not very round, while that of the third toe creates a sharp point due to it extending far beyond the outer intertrochlear notch. The size also matches the extant lesser flamingo, withP. siamensis being more robust than its modern relative and only slightly larger.Phoeniconaias siamensis is diagnosed by the following characteristics. On the supratendinal bridge of thetibiotarsus a large prominence is present. Large cotyla can be seen on the tarsometatarsus and the groove that receives the musculus fibularis is notably furrowed. Thehumerus bears a deep impression for thebrachialis muscle and the ulna possesses a sharp tuberosity. The trochlea of the third toe shows the sharpened point typical for the genus and the distal foramen are located above the intertrochlear notch.