HAMMERHEAD BAT (male) of BIG-LIPPED BAT Hypsignathus monstrosus ©Sarah H. Olson
This is the largest bat in continental Africa, with wingspans approaching 1 m, or about 3 ft, and males almost twice as heavy as females.
Males and females also greatly differ in appearance, making it the most sexually dimorphic bat species in the world. This differences include several adaptations that help males produce and amplify vocalizations: the males' larynges (vocal cords) are about three times as large as those of females, and they have large resonating chambers on their faces. Females appear more like a typical megabat, with foxlike faces.
Males have massive resonating chambers on their faces to amplify vocalizations (indicated by dashed line)
Bottom photo is the female Hammerhead Bat ©Alamy Stock photos