New Jersey Butterfly Club

Southern Cloudywing

Thorybes bathyllus

Identification: Small—1.45” (smaller than Cabbage White). Above: FW and HW dark brown, with several variable but fairly large white spots in FW forming a broken band. Second spot in from leading edge of FW is hourglass-shaped. When fresh, both wings have pale tan fringes checked with brown (although HW fringes sometimes plain white). Below: FW and HW mottled dark brown, with slightly contrasting purplish-brown bands on HW and prominent pale marks visible in FW. Shows pale (sometimes violet) frosting along wing margins when fresh. Other: Palps ("face") white; white ring over eye is bold and continuous; and antennal clubs have a white mark at bend near tip.

NJ Status and Distribution: Resident. Fairly common and widespread. More common than Northern Cloudywing in South Jersey but usually less common than Northern in North Jersey.

Habitat: Dry to moist fields, including hayfields. Uncommon in gardens.

Flight Period: One brood in North Jersey, from mid-May into August. Extreme dates: 5/9—9/2. Two broods in Central and South Jersey, the first in May-June and the second in late July into September. Extreme dates: 4/26—9/13.

Caterpillar Food Plants: Legumes such as clovers (Trifolium), bush-clovers (Lespedeza), and tick-trefoils (Desmodium).

Overwintering Stage: Caterpillar.

Good Locations: Flatbrookville, Ramapo Mountain SF, Voorhees SP, Mountainside Park.

Comments: Can be difficult to separate from Northern Cloudywing. Both species overlap in space and time and share the same habitats, so hybridization is possible, which may account for some individuals that are intermediate in appearance. Three marks are often used to attempt the identification: (1) Southern has larger FW spots above, and has an hourglass-shaped spot near middle of leading edge of FW; (2) Southern's "face" is white and its white eyeline is bold and continuous, while Northern has a brown "face" and a thin, interrupted white line curving over the eye; and (3) Southern has a pale patch at bend of antennal club not seen in Northern. If your butterfly doesn't display all 3 characteristics of either Southern or Northern, consider your ID to be tentative. We've all had to write "cloudywing sp." in our field notes at one time or other!

Both cloudywings are somewhat unusual in the sense that the same plants are very important to both caterpillars and adults. Caterpillars feed exclusively on legumes, and adults often nectar at clovers such as Red Clover (Trifolium pratense) and peas such as Everlasting Pea (Lathyrus latifolium).