Insect specialized for digging deep into flowers can go shallow on occasion
The “tongues” of South Africa’s long-tongued flies are certainly long, but they’re not flexible. So a fly has to hover at a distance to sip from a flower’s shallow nectar cup, as seen in the above photograph, which was honored in the 2015 BMC Ecology Image Competition.
The drinking tube on this particular species, Prosoeca ganglbaueri, can grow up to 5 centimeters long. When folded backward during flight, about half of it sticks out behind the fly’s body. Extreme length lets flies either dabble in shallow blossoms or reach into flowers with deeper nectar tubes. As the mouthparts of various long-tongued flies lengthened through the ages, more than 120 flower species, including Zaluzianskya microsiphon, coevolved longer tubes.
Most of these fly-specialist flowers bloom pink or white. But