True thrushes are medium-sized mostly insectivorous or omnivorous birds in the genus Turdus of the wider thrush family, Turdidae. The genus name Turdus is Latin for "thrush". The term "thrush" is used for many other birds of the family Turdidae as well as for a number of species belonging to several other families.
The genus has a cosmopolitan distribution, with species in the Americas, Europe, Asia, Africa and Australia. Several species have also colonized some oceanic islands, and two species have been introduced to New Zealand. Some New World species are called robins, the most well known of which is the American robin. Several species are migratory.
While some species are often split out of Turdus, the two small thrushes formerly separated in Platycichla by many authors have been restored to the present genus in recent years. (Wikipedia & Birds of the World)