Spicebush swallowtail
Papilio troilus
Butterfly
Black swallowtail with iridescent blue or blue-green hindwings; larvae are specialists on plants in the laurel family (Lauraceae), primarily spicebush (Lindera benzoin) and sassafras (Sassafras albidum). The caterpillar mimics a small snake when threatened - folding the front of its body and displaying large false eyespots - which is one of the most striking caterpillar defenses in eastern North American forests.
Plan for this species
Location-fit plant set for Chicago, IL: host and specialist plants first, then nectar, fruit, seed, foliage, and shelter plants that still fit the current and mid-century climate read.
2 essential relationships / 1 supporting plant
Host/specialist links: 2
Forage/pollination links: 1
Shelter links: 0
Relationship roles: 2
Northern spicebush
Essential / Larval host plants
NC State Plant Toolbox documents spicebush as the primary larval host for Papilio troilus (spicebush swallowtail), supporting two generations per year from April through October. The caterpillar's snake-mimicking defense (folding to display large false eyespots) is one of the most striking caterpillar adaptations in eastern forests.
Sassafras
Essential / Larval host plants
NC State documents sassafras as a larval host for the spicebush swallowtail (Papilio troilus, Lauraceae specialist); spicebush (Lindera benzoin) is the canonical primary host and sassafras is the secondary host. Both Lauraceae species together are the realistic conservation strategy for spicebush swallowtail populations.
Tulip tree (yellow poplar)
Supporting / Nectar plants
NC State notes spicebush swallowtails forage on tulip tree blooms; the bloom timing fits the second brood of this species.
Plants in the catalog
Larval host plants · 2
NC State Plant Toolbox documents spicebush as the primary larval host for Papilio troilus (spicebush swallowtail), supporting two generations per year from April through October. The caterpillar's snake-mimicking defense (folding to display large false eyespots) is one of the most striking caterpillar adaptations in eastern forests.
NC State documents sassafras as a larval host for the spicebush swallowtail (Papilio troilus, Lauraceae specialist); spicebush (Lindera benzoin) is the canonical primary host and sassafras is the secondary host. Both Lauraceae species together are the realistic conservation strategy for spicebush swallowtail populations.
Nectar plants · 1
NC State notes spicebush swallowtails forage on tulip tree blooms; the bloom timing fits the second brood of this species.
Range
Eastern North America from southern Ontario to Florida; wherever its Lauraceae hosts grow.
Sources & citations
Cite this page
Use this citation for the Plotwright wildlife record. Use the source cards below to explore the references that informed its taxonomy, range, conservation, host plants, foraging, and habitat.
Plotwright. (n.d.). Spicebush swallowtail (Papilio troilus). Retrieved 2026, August 20, from https://plotwright.com/wildlife/spicebush-swallowtail
Sources used for this record
This record is compiled from the sources below.
BAMONA: Spicebush swallowtail
Species profile for range, flight season, adult nectar use, and Lauraceae larval hosts.
MDC Field Guide: Spicebush swallowtail
State agency species account used for identification detail, larval and adult food, and life-cycle timing. Missouri-scoped, so it is not cited for continental range.
Wikipedia: Papilio troilus
Corroborating reference for spicebush and sassafras host specificity plus caterpillar defensive mimicry.
GBIF: Papilio troilus
GBIF Backbone Taxonomy accepts Papilio troilus Linnaeus, 1758 as a species, matched exactly.
iNaturalist: Papilio troilus
iNaturalist taxon 58525 is the active species Papilio troilus, giving crowd-sourced observation range data.