A defining characteristic of Hipposiderids is their elaborate noseleaf. The noseleaf consists of fleshy protrusions on top of a U-shaped rhinarium (i.e., the wet surface surrounding the nostrils). Hipposiderids have an erect transverse leaf within the noseleaf as well as smaller accessory leaflets. The common name of many genera corresponds to the shape of the noseleaf. For example, flower-faced bats have two circular lateral leaflets, the smaller of which is superimposed onto the larger, resulting in a noseleaf resembling the petals of a flower. Differences in noseleaf characteristics are commonly used to discern between genera. These 'appendages' are thought to be related to nasal echolocation, and may help to focus and modify echolocation signals.
Pelage of hipposiderids varies greatly both between and within taxa. Pelage can be white, light beige, pale yellow, dark yellow, orange, red, red-brown, light brown, dark brown, gray, or dark gray. Some species have white patches of fur, while others have 2 different color phases. Often, venter pelage is lighter than dorsum pelage. Pelage also differs interspecifically by length and texture or silkiness. Hipposiderid skulls have a number of unique features that differentiate them from other bat families. For example, they have no post-orbital processes, the nasal portion of the premaxilla is absent, and the premaxilla is not fused to the maxilla. They have dilambdodont molars , and their dental formula is I1/2 C1/1 P1–2/2–3 M3/3, giving them a total of 28 to 30 teeth. Hipposiderids do not have a tragus, the fleshy protuberance present at the opening of the ear in many bats. A membrane spanning the dorsal surface of the head connects their ears, which exhibit a great deal of variation in size.
Hipposideridae shares many traits with the family Rhinolophidae, and some accounts consider Hipposideridae a sub-family of Rhinolophidae. Both hipposiderids and rhinolophids lack post-orbital processes and the nasal portion of the premaxilla, as well as having a premaxilla that is not fused to the maxilla, dilambdodont molars, and a U- or horseshoe-shaped rhinarium. However, hipposiderids can be differentiated from rhinolophids using a number of different characteristics. Hipposiderids generally have a more rounded noseleaf, while the noseleaf of rhinolophids is spear-like and pointed. Hipposiderids have only two bones in each toe, while rhinolophids have three in all except the first toe, which has two. Rhinolophids always have three lower premolars on each side of the mandible and hipposiderids have only two. The two families also differ in the structure of their shoulder and hip girdles. Finally, rhinolophids have a sella, a flattened leaflet in the middle of the noseleaf structure, that is not present in hipposiderids.
Other Physical Features: endothermic ; heterothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: sexes alike