Field Guide Descriptions: Leckie and Beadle (2018) | Online Resources: MPG, BugGuide, iNaturalist, Google, BAMONA, GBIF, BOLD | Technical Description, Adults: Clarke (1941); Hodges (1974) | |
Adult Markings: The following is primarily based on the description by Clarke (1941). The labial palp is white and the second segment is suffused with blackish fuscous exteriorly. The third segment has a fuscous spot at the base anteriorly and a broad black sub-apical annulus. The antenna has a dark base, while the remainder is light fuscous with narrow and indistinct gray annulations. The head and thorax are gray, with the latter suffused with fuscous. The forewing is light gray to grayish brown and lightly shaded and strigulated with brown. The costa from the base to the middle of wing is slightly lighter. Beginning at the end of the cell there is a sinuous narrow black bar that widens anteriorly and continues to about one-third the wing length. The outwardly curved portion at the beginning of the cell is followed by a rapidly fading and spreading brownish shade. Between the discal portion of the bar and the costa, there is a short, poorly defined blackish-fuscous bar followed by a blackish-fuscous spot before the apex. A series of blackish-fuscous spots extends from the apex around the termen. The cilia are pale gray and lightly suffused with brown. The hindwing is shining gray with a fine terminal brown line. The cilia are lighter and shining, with a narrow sub-basal and two sub-terminal faint brown bands. The legs are shining creamy white and strongly overlaid with blackish fuscous except at the joints and on the hind tibia. The abdomen is sordid ochreous and faintly suffused with fuscous beneath. |
Wingspan: 24-31 mm (Clarke, 1941) |
Forewing Length: 11-15 mm (Hodges, 1974) |
Adult Structural Features: Clarke (1941) provides detailed descriptions and illustrations of the male and female genitalia. This species and S. packardella have very similar genitalia. They can be most easily separated based on the number and shape of the spines on the cornuti of males, and the number of inwardly directed projections of the signum of females (Hodges, 1974). |
Adult ID Requirements: Identifiable from good quality photos of unworn specimens. |
Immatures and Development: The larval ecology and life history are undocumented. |