This is a much larger species than our common Swift and has only visited these islands on very rare occasions, almost all the examples obtained having been taken in the south of England. It breeds in the high mountain ranges of Central and Southern Europe, and winters in Africa. From our common species it may be distinguished by its larger size, browner colour, and light under parts. Length 8 in.; wing 8·45 in.

Another species, the Needle-tailed Swift (Acanthyllis caudacuta) has occurred on two occasions in England. It breeds in Central Asia, migrating in winter to Australia, and except for these two instances is unrecorded from Europe.