Spicebush Swallowtail (Papilio troilus) (Linnaeus, 1758)

Diagnosis: This species belongs to a mimicry complex based on the Pipevine Swallowtail (Battus philenor) as the model. Papilio troilus is a black swallowtail with large blue iridescent spots on the hindwing of the female and a greenish-blue wash on the hindwing of the male. Both sexes have green submarginal lunulate markings. The hindwing underside has two rows of large orange spots with extensive blue scaling between them. Unlike the other members of the complex, the tails of troilus are spoon-shaped. Wingspan: 70 to 90 mm.

Subspecies: Only the nominate subspecies is found in Canada.

Range: A woodland butterfly of the eastern U.S., the Spicebush Swallowtail reaches into Canada only in southwestern Ontario except for one stray in extreme western Ontario. It is a permanent resident of the Carolinian forests north of Lake Erie and has been taken as far east as Toronto.

Specimen collection data

Description of this image follows
Spicebush Swallowtail
(Papilio troilus troilus)
female. Wainfleet, Ont. J. Kamstra

Similar Species: The Pipevine Swallowtail (B. philenor), the Black Swallowtail (P. polyxenes females), and the Eastern Tiger Swallowtail (P. glaucus black females), which are all part of a mimicry complex. [compare images]

Early Stages: The larva of this species is noted for its very realistic "eye-spots" behind its head. When alarmed it arches up its back to give it the appearance of a small snake's head. Foodplants are trees and shrubs characteristic of the Carolinian forest: Spicebush (Lindera benzoin), Sassafras (Sassafras albidum), and the Tulip Tree (Liriodendron tulipifera).

Abundance: The Spicebush Swallowtail tends to be very local and uncommon in most of its limited Canadian range. It is considered common at Point Pelee. It sometimes shows up as a migrant, usually mixed in with other species.

Flight Season: In Canada and the northern U.S., the adults fly in May and June, with a second generation appearing in July and August.

Habits: This butterfly is associated with deciduous forests and woods edges. It likes to mud-puddle, often in the company of other species.

Remarks: In Canada, the Spicebush Swallowtail can most easily be seen at Point Pelee National Park and at Pinery Provincial Park, in Ontario.

© 2002. This material is reproduced with permission from The Butterflies of Canada by Ross A. Layberry, Peter W. Hall, and J. Donald Lafontaine. University of Toronto Press; 1998. Specimen photos courtesy of John T. Fowler.