Key to the Swallowtails

	This group is fairly straight forward to separate except P. machaon and P. saharae which overlap in extreme desert regions of N Africa. Geography is a useful guide.

1	1a) Swallowtail, Papilio machaon - All of Europe, absent from most of the UK. - Underside forewing. Outer edge of dark post discal band is straight. - Forewing basal areas black. - Veins lined black. 1b) Corsican Swallowtail, Papilio hospiton - Only on Corsica and Sardinia, but flies with P. machaon above. - Underside forewing. Outer edge of dark post discal band is deeply indented. - Unh white basal steak is long and sweeps to a very acute angle to the costa. - Veins lined black. 1c) Southern Swallowtail, Papilio alexanor - Greece, Greek islands and SE France (plus the extreme NW Italy). - Underside forewing. Dark post discal band is reaches the costa. - Forewing basal areas are not black. - Veins not lined black. 1d) Desert Swallowtail, Papilio saharae - Desert regions of S Morocco, S Algeria and S Tunisia. - Almost indistinguishable from P. machaon. Larvae differ distinctly. - Antennal segment count is 30-31 in P. saharae, 33-36 in P. machaon.
		1a) one row of submarginal spots. e.g. Mountain Alcon Blue, M. rebeli
		1b) two rows of submarginal spots, Large Blue M. arion
		1c) no submarginal spots, Dusky Large Blue M. nausithous

Identification Swallowtails Papilio