Siberian chiffchaff to be a full species due to its distinctive plumage and vocalisations, being similar to "P. s. sindianus" in these respects. Common chiffchaffs (of the nominate race) and Siberian chiffchaffs do not recognize each other's songs. Pending resolution of the status of the form "fulvescens", which is found where the ranges of common chiffchaff (of the race "abietinus") and Siberian chiffchaff connect and may or may not be a hybrid between these, "tristis" is maintained in "P. collybita" by most checklists. Siberian chiffchaff Siberian chiffchaff ("Phylloscopus (collybita) tristis") is a leaf-warbler which is usually considered a subspecies of the common
Eastern Canary Islands chiffchaff Eastern Canary Islands chiffchaff The eastern Canary Islands chiffchaff or Lanzarote Island chiffchaff ("Phylloscopus canariensis exsul") is an extinct subspecies of the Canary Islands chiffchaff endemic to the island of Lanzarote – and possibly also Fuerteventura – in the Canary Islands, Spain. The eastern Canary Islands chiffchaff was more chestnut-backed and shorter-winged than the western Canary Islands chiffchaff, "Phylloscopus canariensis canariensis". These birds were formerly considered subspecies of the common chiffchaff but separated (Clement & Helbig, 1998; Sangster "et al.", 2001) due to their morphological, bioacoustical, and mtDNA sequence differences (Helbig "et al.", 1996). Apparently this subspecies was already very