Slender-billed grackle

The slender-billed grackle (Quiscalus palustris) is an extinct species of grackle in the Icteridae (New World blackbirds) family of birds. The species was closely related to the western clade of the great-tailed grackle, from which it diverged quite recently, around 1.2 million years ago.

The slender-billed grackle was endemic to central Mexico, especially in the Valley of Mexico and the Toluca Valley. Early observations recorded by Franciscan friar Bernardino de Sahagún in the 16th-century manuscript General History of the Things of New Spain indicate that the species was found in cultivated areas and towns. Later records indicated that it might be a marsh specialist. The species became extinct around the turn of the 20th century.