Erynnis martialis, commonly known as the mottled duskywing, is a species of butterfly in the family Hesperiidae.

Adults feed on nectar from flowers of Bush houstonia, Gromwell, Verbena stricta and other plants.

[5] Main threats posed to mottled duskywing populations are habitat loss, fragmentation and invasive species control measures.

[6] Urbanization, suburban sprawl, agriculture and logging have destroyed many oak savanna habitats that the mottled duskywing rely on.

[7] The spraying of DDT and carbaryl to control the population of the invasive gypsy moth also pose a major threat to the success of the species.