Spotted on our property Monte Horizonte 

The Iberian Chiffchaff (P. ibericus) is brighter, greener on the rump, and yellower below than Common Chiffchaf, and has a tit-tit-tit-tswee-tswee song.

It was initially named P. brehmii, but the type specimen of that taxon is not an Iberian Chiffchaff. This species is found in Portugal and Spain, west of a line stretching roughly from the western Pyrenees via the mountains of central Spain to the Mediterranean; the Iberian and Common Chiffchaffs co-occur in a narrow band along this line.

Apart from the northernmost section, the precise course of the contact zone is not well-documented. A long-distance migrant, this species winters in western Africa. There is hybridization in the contact zone, almost always between male P. ibericus and female P. c. collybita, and hybrids apparently show much decreased fitness; hybrid females appear to be sterile according to Haldane's Rule.

Regarding the latter aspect, it is interesting to note that the Iberian Chiffchaff apparently is the oldest lineage of chiffchaffs and quite distinct from the Common Chiffchaff.

Iberian Chiffchaff, Iberische Tjiftjaf, Iberienzilpzalp, Felosa-iberica, Mosquitero Iberico

Other synonyms:

Catalan: Mosquiter ibèric
Czech: Budní?ek iberský, budníèek iberský
Danish: Iberisk Gransanger
German: Iberienzilpzalp, Spanischer Zilpzalp
English: Iberian Chiffchaff, Iberian Chiff-chaff, Western Chiffchaff
Spanish: Mosquitero Ibérico
Estonian: ibeeria väike-lehelind
Basque: Mosquiter ibèric
Finnish: iberiantiltaltti
French: Pouillot ibérique
Galician: Mosquiter ibèric , Picafollas ibérico
Icelandic: Grenisöngavri
Italian: Luì iberico
Japanese: iberiachafuchafu
Latin: Phyllopneuste brehmii, Phylloscopus brehmi, Phylloscopus brehmi brehmii, Phylloscopus brehmii, Phylloscopus bremhii, Phylloscopus collybita brehmii, Phylloscopus collybita ibericus, Phylloscopus collybitus brehmii, Phylloscopus ibericus, Phylloscopus indicus
Dutch: Iberische Tjiftjaf
Polish: swistunka iberyjska, ?wistunka iberyjska
Portuguese: Felosa-ibérica
Slovenian: iberska listnica
Swedish: Iberisk gransångare
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