New World leaf-nosed bats are a common and diverse group that includes around 143 species, placed in 49 genera. The relationships of these genera are not fully understood. Currently, living phyllostomids are arranged in 7 or 8 subfamilies. The Phyllostominae includes carnivorous, insectivorous, and fruit-eating species. Members of this subfamily tend to have a number of primitive characteristics. The Glossophaginae is made up of nectar feeders, bats with remarkable adaptations of tongue and rostrum for extracting nectar and pollen. They are also capable of hovering flight. The monophyly of this group is open to question; some nectar feeders are sometimes placed in the separate subfamily, Lonchophyllinae. The Carolliinae includes a small group of frugivores, possibly related to glossophagines. The subfamily Stenodermatinae is the largest of the family. Stenodermatines are primarily fruit-eaters, and many show strong specializations for frugivory. The Brachyphyllinae is a group of fruit and nectar eating species restricted to the West Indies. They may be related to stenodermatines or glossophagines. Finally, the Desmodontinae comprises the vampires, a group of 3 species that rely entirely on blood for food.
The most conspicuous characteristic of phyllostomids is a "
noseleaf", a fleshy protuberance from the nose that ranges from in size from nearly as long as the head to, in a few species, complete absence. Many species also have bumps, warts, and other protuberances on the head near the noseleaf or on the chin. In most species, the noseleaf is a relatively simple spear-shaped structure, not nearly as complex as that of rhinolophids.
Phyllostomids lack postorbital processes, and their premaxillae are complete and fused to each other and to the maxillae. The palatal branches of the premaxillae isolate two lateral palatal foramina. The bony tails of phyllostomids vary from apparently absent to long, even extending slightly beyond the edge of the uropatagium. A tragus is present.
Bats of this family range in size from very small (forearm 25mm long) to extremely large; Vampyrum spectrum, with a forearm of around 110mm, is the largest bat in the New World. Some species have complicated color patterns, often including stripes on the head or back or white tufts of fur on the shoulders. Species of phyllostomids differ greatly in morphology, correlated roughly with their dietary habits. Nectar feeding species are small and have long muzzles and extremely long tongues tipped with a brush-like structure. Their teeth tend to be relatively small and simple in structure. Their dental formulae and molar shape vary considerably among species. Carnivorous species (e.g., Chrotopterus) are large and have especially large, heavy dentition. Frugivorous species (e.g., Ametrida) may be large or small; their teeth are usually somewhat simplified and flattened. In contrast, insectivorous species are mostly small, and most have complex, sharply crested teeth. Perhaps the strangest dentition is found in the vampire bats, which have enlarged and bladelike incisors and canines, but molars extremely reduced in size and complexity.
Phyllostomid bats can be found in the Americas, from the southwestern United States south to northern Argentina, including the West Indies. Their fossil history extends to the Miocene.
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