A small Flower Fly of 7 mm in length. It has an abdominal pattern that I can't find on the internet as well as a hairy bicolored scutellum. It is probably a species of Allograpta. Family Syrphidae. See notes below.
Garden lights, semi-rural residential area, San Cristobal de Las Casas, Chiapas, Mexico, 2,200 meters.
Dr. Christian Thompson, a Syrphid specialist at the Smithsonian in Washington has confirmed that this is Allograpta neotropica. Southern Mexico is probably its northernmost range. Sergio Monteiro found this fly in Brazil in 2015: (http://www.projectnoah.org/spottings/112...) and Juand.duenas also spotted this fly in Colombia in 2012: (http://www.projectnoah.org/spottings/131...). Allograpta neotropica appears on a list of 11 Syrphids reported from the Brazilian Amazon (http://syrphidae.inpa.gov.br/syrphidae/i...) and there is an unidentified picture of A. neotropica from the island of St. Martin in the Lesser Antilles (Caribbean). This species was described in 1936 by Curran. It is surprising how rarely it is encountered.