New York Natural Heritage Program
Chain Fern Borer Moth
Papaipema stenocelis (Dyar, 1907)
Insects

Identifying Characteristics [-]
The chain fern borer moth has orange forewings that include some brown and purple shading. The brown median line is slightly bent. The postmedial line is double and slightly rounded. The most distinctive feature is that all three spots on the forewings are white, and they form narrow vertical bars. The orbicular and claviform spots are almost joined. The hind wings are yellow with grayish-brown veins, and the outer portions are shaded. The wingspan is 35-40 mm (Covell 1984). Frass of larvae is orange (Hessel 1954; Wagner et al. 2008). The early instars (stages) of many larvae in the genus Papaipema are colorful, with rings or whitish stripes on a maroon, pink, purple, or brown body. Later instars become whiter (Wagner et al. 2008). The species is most easily identified as an adult moth (Wagner et al. 2008; NatureServe 2010), and its identification should be confirmed by an expert if based on a photograph or sign other than an adult specimen (NatureServe 2010).

Best Life Stage for Proper Identification [-]
The adult is the best life stage for identification (Wagner et al. 2008; NatureServe 2010).

Behavior [-]
Chain fern borer moths fly from late August-early October (Covell 1984; Wagner et al. 2008). In New York State, they have been documented to fly in early October. Typically, they tend to fly within 10 m of Virginia chain fern (Woodwardia virginica) patches. However, although they usually do not fly far from Woodwardia virginica patches, females seem to disperse more than males, particularly after laying their eggs. Females have been documented more than 2 km from suitable larval habitat containing Woodwardia virginica (NatureServe 2010). Females lay their eggs on and near Woodwardia virginica, the larval host plant (Wagner et al. 2008). Larvae burrow from the tips of stems (early) to the roots of Woodwardia virginica. They push orange frass out of the tunnel, where it collects around and beneath the tunnel entrance. Larvae pupate in the soil near the host plant and emerge as adults late the next season (Wagner et al. 2008).

Diet [-]
The larvae bore in the lower stems and later roots of the Virginia chain fern (Woodwardia virginica) (Hessel 1954; Covell 1984; Wagner et al. 2008).
Chain Fern Borer Moth Images
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The Best Time to See
The best time to see the chain fern borer moth is during its flight season, generally from late August-early October (Covell 1984; Wagner et al. 2008). In New York State, the moth has been documented to fly in early October.
J F M A M J J A S O N D
Present Reproducing
The time of year you would expect to find Chain Fern Borer Moth present (blue shading) and reproducing (orange shading) in New York.