Material examined: Type specimens. ♂ holotype (VTEC SPC000296), 1 ♂ paratype (VMNH SPC000297), and 2 ♀ paratypes (VTEC SPC000294, 295) from Virginia, Wythe County, N slope Fosters Falls Mountain, cove near road (36.89021°N, - 80.8376°W, Elev. 657 m), 29 May 2004, tulip, oak, maple, rhododendron, moist cove (Coll: P. E. Marek). Material examined listed in Supp Table 2 (online only).

Diagnosis: Adult males of Appalachioria sierwaldae n. sp. are distinct from other apheloriine species based on the following combination of characters: Gonopods. Gonopodal acropodite strongly curving ventromedially and with a strong distal cingulum, separating it from Apheloria and Rudiloria (Fig. 7). Prefemoral process short and stout. Post-cingulum area expanded, wider than pre-cingulum area. Distal zone strongly curved medially into a long, uncinate, thin tip. Color. Tergites with yellow paranotal spots and yellow metatergal spots (Fig. 5I), but sometimes with orange metatergal spots (Fig. 5H). Black background. Collum with yellow lateral and anterior spots, sometimes with yellow or orange posterior spots, or lacking a posterior spot.

Description: Supp Table 3 (online only). Based on Holotype (♂) SPC000296.

Measurements (mm): BL = 40.0, CW = 7.0, IW = 4.7, ISW = 1.4, B11W = 9.4, B11H = 5.4.

Variation: No significant variation from the holotype was observed.

Ecology: Individuals of Appalachioria sierwaldae n. sp. were found in an Appalachian cove forest that included tulip, oak, maple, and rhododendron.

Distribution: Only known from the type locality on Fosters Falls Mountain in eastern Wythe County, Virginia.

Etymology: This species is named for Dr. Petra Sierwald of the Field Museum of Natural History. The specific name is a genitive noun derived as a matronym.