Marathyssa inficita is a species of insect belonging to the family Lycaenidae. It is commonly known as the "Eastern Tailed-Blue." This small butterfly has a wingspan of about 1 inch and is characterized by its vibrant blue coloration with black margins and a distinctive tail-like projection on its hindwings. It is found in the eastern regions of North America and is known to inhabit open grasslands, meadows, and gardens.