Streaked Scrub Warbler Scotocerca inquieta sensu lato has a large distribution area that extends from Western Asia through the Arabian Peninsula and into the Atlantic coast of North Africa. There are eight subspecies including two in southern Morocco, S. i. saharae in the east and S. i. theresae in the southwest.
In a recent paper published in Dutch Birding, Bergier et al. (2013) concluded that it is doubtful whether the external differences between saharae and theresae, as in colour and striation, are related to their supposed range. Therefore both Moroccan subspecies could be better treated as synonyms, therefore rendering theresae as an ecological type rather than a subspecies.
Recent genetic studies have placed the genus Scotocerca in its own separate family Scotocercidae. Given that the North African birds differ greatly in appearance and sound from the nominate subspecies S. i. inquieta in the Middle East, it would be no surprise when more than a single species should be recognised within Scotocercidae.
Bergier, P., Thévenot, M., van den Berg, A.B. & The Sound Approach (2013). Distribution, habitat, identification and taxonomy of Streaked Scrub Warbler in Morocco. Dutch Birding 35: 107–121. PDF
Update: Saharan Scrub Warbler split
The North African taxon (Scotocerca saharae) was split from the Asian one (Scotocerca inquieta) in the updated version of Collins Bird Guide. The authors gave the name Saharan Scrub Warbler to the North African species and Levant Scrub Warbler to the Asian one. With this split the Saharan Scrub Warbler joins other endemic and near-endemic birds of Northwest Africa (Maghreb).
Read the full list of changes in the revised edition of the Collins Bird Guide in Rare Bird Alert UK.
Le nom français serait Dromoïque du Sahara ou Dromoïque du Maghreb.
.الإسم العربي: نمنمة الشجر الصحراوية أو نمنمة الشجر المغاربية