(Figs. 5154, Map 33)
Identification: Forewing length 15.0–19.0 mm. This is a variable species with the forewing ground color ranging from reddish brown to dark gray. Distinguishing characters include the light cream to tan head and prothorax contrasting with the reddish brown thorax, the distal margin of the reniform spot is sharply angulate, black rectangular spot between orbicular and reniform spots, and in the males the long scales associated with the genitalia are bright reddish brown and tan. Hindwing is dirty white to pale gray with a faint discal spot and a very faint subterminal line in most specimens. Some specimens appear to have a washedout appearance to the forewing with the rectangular spot absent and the pattern of lines and spots faint. Most of these specimens have a more uniform reddish brown forewing ground color.
Flight period: Collected from late June to early August.
Collected localities: North Carolina: Haywood Co., Balsam Mountain picnic area on Flat Creek Trail, Polls Gap on Hemphill Bald Trail, Purchase Knob, Purchase Knob E of house forest, Purchase Knob N of house forest, Purchase Knob ATBI Plot, Polls Gap on Rough Fork Trail; Swain Co., Beetree Ridge, Big Cove Road site c, 1.2 mi NE of Clingman’s Dome parking lot on Noland Divide Trail, 5.6 mi SW of Jct. 441 and Clingman’s Dome Road Noland Divide Trail, 3.3 mi NE of Clingman’s Dome parking lot on Fork Ridge Trail, Indian Gap on Clingman’s Dome Road, Tricorner Knob. Tennessee: Cocke Co., Albright Grove ATBI Plot, 0.25 mi inside entrance to Cosby, Snakeden Ridge ATBI Plot; Sevier Co., Brushy Mountain ATBI Plot, Chimney Tops Trail, 1.3 mi W of Jct. 441 and Clingman’s Dome Road on Road Prong Trail, 6 mi S of Sugarlands Visitor Center Cove Hardwood Forest, 7 mi S of Sugarlands Visitor Center, Jake’s Creek Trail at Campsite 27. (130 specimens)
MAP 33. Collecting localities of Diarsia jucunda. Elevation range: 1480–4924 ft. (451–1501 m)
Elevation range: 1350–6000 ft. (411–1829 m)
General distribution: This species is distributed from Newfoundland and central Ontario, west to northern Michigan and Wisconsin, and south to Ohio. In the Appalachians it is found as far south as North Carolina (Lafontaine 1998). The collections from GSMNP are new records for the state of Tennessee.
Larval hosts: Little is known about the host plant preferences of this species, but it is probably a general feeder (Lafontaine 1998). Rockburne and Lafontaine (1976) reported larvae feeding on grasses (Poaceae), and McCabe (1991) fed larvae on common dandelion (Taraxacum officinale G. H. Weber ex Wiggers, Asteraceae).