Megaselia Rondani (total of 27 photos of 13

mating events examined: Figure 8 C-H)

Given that Megaselia is one of the largest genera of the animal kingdom with about 1700 species described (Brown 2022), it would not be surprising if diverse mating patterns were found across the genus. Some of the photos examined show a standard mating position (Figure 8F). Others show a much smaller male, the female with her wings slightly lifted and the male touching her abdomen during mating (Figure 8H). Other than this variation in position, nothing else noteworthy was observed based on the photos.

Brown and Porras (2015) described an extravagant display of Megaselia females from Costa Rica which evert abdominal sacs and flutter their wings to attract mates (10.5281/zenodo.14628212). They also highlighted that abdominal eversible sacs and display behaviour are probably present in the females of other species in Megaselia and in other phorid genera (such as Phalacrotophora, Physoptera and Syneura) as they have similar morphology of the abdomen with large areas not covered by tergites. We confirmed this prediction here by documenting abdominal sacs eversion in at least three other groups (Figures 6G,H, 7E,F, 10C). Additionally, we found photos of groups of Megaselia females aggregating on leaves (Figure 8C–D). One possible explanation for such aggregation could be to display and attract males, another possible example of sex-role reversal in the genus (Sivinski 1988).