northern pine sphinx

Northern pine sphinx is a common, highly variable, medium sized, sphinx moth. It occurs in the United States from Maine to New Jersey, west to Minnesota, and south along the Appalachian Mountains to northern Georgia.

Adults are active in June and July. They are found in coniferous and mixed forests. There are no records of them feeding. It they do feed it would be on the nectar from tubular flowers. In Minnesota, the larva feed on the foliage of eastern white pine, jack pine, red pine, Scots pine, and tamarack. In other areas, they also feed on pitch pine, and possibly on pond pine, loblolly pine, and longleaf pine.

Adults are 1 1⁄16″ to 1⅜″ (27 to 35 mm) in length and have a 1¾″ to 2⅜″ (45 to 60 mm) wingspan. Moth size is sometimes given in terms of forewing length, which in this case is ⅞″ to 1⅛″ (23 to 29 mm).

On the front of the head, at the lower margin of the forehead (frons), there is a rounded to angled projection. The tongue is moderately long. It barely reaches the end of the thorax.

The forewing is long, slender, and pointed, and the outer margin is slightly concave. It is slate gray with black lines and dashes, brownish shading, and a peppering of white scales. The antemedial (AM) line is deeply curved. The postmedial (PM) and subterminal (ST) lines are jagged. The AM and PM lines are bordered by pale shading above and dark shading below. There are two heavy black dashes in the median area. The longest of these touches the ST line. Sometimes there is a third, less bold dash closer to the inner margin. In the basal area there is usually a rich brown patch on the inner margin.

The hindwings are pale gray.

The mature caterpillar is up to 2″ (5 cm) long and lime green. It has bold, cream-colored, addorsal, supraspiracular, spiracular, and subspiracular stripes. The breathing pores (spiracles) are black. There are often dull red splotches above in the middle (dorsally), above the abdominal leg-like structures (prolegs), and on the prolegs. The head is triangular and mostly reddish-brown. There is a black inverted V mark at the top, and there is a yellow stripe on each side margin. Mature caterpillars are seen from June to November.

Total length: 1 1⁄16″ to 1⅜″ (27 to 35 mm)

Wingspan: 1¾″ to 2⅜″ (45 to 60 mm)

Forewing length: ⅞″ to 1⅛″ (23 to 29 mm)

Coniferous and mixed forests

One generation per year: June and July

Adults are active at night and will come to lights.

Foliage of tamarack and many pine species

Unknown

Sources

4, 21, 24, 29, 30, 75, 82, 83.

Common

Luciearl
9/5/2024

Location: Lake Shore, MN