Graphium nomius, the spot swordtail,[1][2] is a butterfly found in South and Southeast Asia that belongs to the swallowtail family.

[1][2] One of the grandest sights is a host of spot swordtails mud-puddling or swarming around a flowering forest tree.

It is known from southern and eastern India (including Sikkim and Assam), Sri Lanka, Nepal, Bangladesh, Myanmar, Thailand, Vietnam, Laos and Kampuchea.

It differs from Graphium antiphates chiefly in the greater width of the black markings on the upperside, especially of the basal and subbasal bands that cross the forewing, both of which also extend to the dorsum.

[5] Generally found in deciduous forest areas, among bushes with lesser secondary growth.

Large numbers can be seen settling on damp roads and wet patches, especially in hot summers.

The most usual colour......is black, banded on the sides with narrow white stripes, except on the first three or four segments and the last., on which there is more or less rusty red; but the shade varies very much, and in some the groundcolour is green."

(Davidson and Aitken)[3] Has the usual horn which characterizes this group, and also two short processes on the head, and is of some shade of earthy brown.

The pupae of the previous year's brood emerge, seek mates and lay eggs just as the tree puts out new growth.