Identifying island-mainland bee populations with wings
Wing venation can be used to accurately identify bees (Hymenoptera: Anthophila) to species. Wing venation patterns alone, captured by geometric morphometrics, may also be sufficient to classify variation between populations of the same species. An application of this method is presented here with bees in the genus Halictus (Hymenoptera: Halictidae). Specimens were collected from Santa Cruz Island and Santa Barbara, California. The Pacific Ocean provides a physical barrier between mainland and island populations. To analyze wing venation patterns, forewings were removed, slide mounted, imaged, and annotated with digital landmarks using TPS morphometric software for approximately 360 specimens and 9 landmarks. Data collection for this project was conducted remotely during the COVID-19 pandemic with inexpensive equipment. Results show 100% accurate discrimination of three Halictus species and less accurate discrimination of two populations of one species, H. tripartitus, collected either from mainland or island locations.