The exemplar of the pictures I saw on March 23, 2016, in the village of Alcollarín (Caceres, Extremadura, Spain)
This may be the first hybridization Sardinian Warbler known because I have consulted Handbook of Avian Hybrids of the World, McCarthy, and the Warblers Sylvia, of Shirihai et al and the Internet, I have found no record about it.
As can be seen in the photographs, the physiognomy and plumage base are closely identified with the species Melanocephala Sylvia, however there are at least three physical characteristics that differentiate it and can be identified with the species Cantillanas Sylvia:
– Plumage brick-red breast.
– Eyes and eye-rings like Cantillans
– Colour of legs like Cantillans.
In addition, I also observed different from the usual behavior of the species Melanocephala:
– The song was similar to Melanocephala, but with different nuances.
– It is unusual in Melanocephala singing in a treetop.
The habitat in which I saw the exemplar is common to both species, Melanocephala like residentes and Cantillans in prenuptial step: river and olive grove mixed with low scrub and grassland.
As to whether it is a hybridization in first and subsequent generations, it is difficult to determine, but I would tip me because it was the first generation, because it is a very rare hybridization never seen before and that physical and behavioral traits seem They are pretty evenly matched. Although this is not critical since not always external physical features correspond to the percentage of DNA that each species have put the hybridization.