A new species of Docosia Winnertz fungus gnat was discovered in western Michigan. One male and four females appeared in a Malaise trap in mostly deciduous woods in spring. Docosia fimbria Taber with its orange and black coloration resembled Docosia dichroa Loew and the newly discovered Docosia walpurga Taber, but male and female terminalia and wing venation indicated specific differences. Females of all three species were associated by comparative anatomy with males, and seasonal phenology was determined.