The West Virginia White is a small, spring butterfly in the Pieridae family (1, 2). They range from northern Minnesota to eastern Quebec and then south through the Appalachians to Georgia (2). This butterfly stays within the shade of the deciduous forests and out of sunny fields (2). In Maryland, they can only be found in Garrett, Allegany, Washington, and Frederick Counties (3) and have a state rank of (S1/S2).
The West Virginia White has a wingspan of about 1.5 inches. Their rounded forewings are mostly translucent and cloudy white with little to no markings (4, 5). The undersides are brownish-grey with dark scaling along the hindwing veins (4, 6). Females often have more grey than males (4).
The West Virginia White is a rare species with one generation per year. Females lay eggs singly on host plants, most commonly toothwort plants from the Mustard family (1, 2, 3, 7); these may include Broad-leaved Toothwort (Dentaria diphylla) and Cut-leaved Toothwort (Dentaria laciniata) as well as rockcresses (1, 3). Unfortunately, females will sometimes lay their eggs on Garlic Mustard (Alliaria petiolata) (7). Garlic Mustard is an invasive weed that contains chemicals toxic to the caterpillars (1, 3). The toxins on the leaves greatly reduce survival through the larval stage, threatening their abundance (7).
Caterpillars begin as a yellowish-green color and darken with maturity. They have short hairs and yellow-green dorsal and lateral lines. This species hibernates as a chrysalis and adults emerge and fly from April to May (8).
The West Virginia White prefers well shaded and moist woodlands containing Toothwort (3, 7, 8). As an adult, they can be seen frequenting several species of violets (8). The most common violet plants in Maryland are the common blue violet (Viola sororia), marsh blue violet (Viola cucullata), field pansy (Viola bicolor), primrose-leaved violet (Viola primulifolia), and striped white violet (Viola striata) (9).
Data from Maryland Biodiversity Project. Includes historical records and may overrepresent the current range of the species.
Forest fragmentation and the spread of invasive Garlic mustard are potential threats to the West Virginia White (5). To help this species we need to preserve their natural habitat where toothwort is common and control the spread of Garlic mustard, a toxic invasive plant.
© 2020 Price Lab for Entomology, Courtney Rogall