New Jersey Butterfly Club

Spicebush Swallowtail

Papilio troilus

Identification: Very large—about 4.1” (larger than Monarch), Above: Mostly black but with blue on HW and a row of pale (often pale bluish) spots along FW and HW margins. Male has a prominent blue-green “cloud” on the HW and more-prominent FW marginal spots. Both sexes lack pale spot near front edge of FW seen in Black Swallowtail. Below: Mostly black but with blue on HW and 2 rows of orange spots. The inner row has one orange spot missing, replaced by an “arrowhead” of blue scales. (In Black Swallowtail this row is complete.)

NJ Status and Distribution: Resident. Common and widespread throughout.

Habitat: Open, sunny, upland fields, wet meadows, and forest edges. Easily attracted to gardens with flowers such as Butterfly Bush, Purple Coneflower, Wild Bergamot, and milkweeds.

Flight Period: Mid-April to mid-October with peaks in late spring (May-early June) and mid-late summer (August). Extreme dates: North Jersey 4/17—10/20; South Jersey 3/28—11/3.

Caterpillar Food Plants: Spicebush (Lindera benzoin), a native shrub of wet woods; and Sassafras (Sassafras albidum), a native deciduous tree of upland forest edges and hedgerows.

Overwintering Stage: Pupa.

Good Locations: Whittingham WMA, Schooley’s Mountain CP, Merrill Creek Reservoir, Willowwood Arboretum, Bamboo Brook Outdoor Education Center, Great Swamp NWR, Kay Environmental Center, Riverwinds Scenic Trail (West Deptford), and Belleplain SF.

Comments: Planting (or not cutting down) Northern Spicebush and Sassafras on your property will almost guarantee you the pleasure of seeing adults in your garden as well as their spectacular larvae.