Museum, University of Nebraska State


Date of this Version



Annals of Carnegie Museum (July 11, 1984) 53 (article 11): 327-346.


Copyright 1984, Carnegie Museum of Natural History. Used by permission.


Five species of Tonatia (bidens, brasilense, carrikeri, schulzi, and silvicola) are known to occur in Suriname. Tonatia bidens and silvicola are the largest in overall size (forearm length over 50 mm and greatest length of skull over 27.0 mm). However, T. bidens has a broader postorbital region (5.0 mm or more) and narrower mastoid region (less than 13.0 mm). The lower incisors of T. bidens are also noticeably broader than those of T. silvicola. These two species were found throughout most of the forested areas of Suriname. T. bidens displayed no secondary sexual variation in nine measurements tested, whereas female T. silvicola were significantly larger than the males in four of these measurements.

Tonatia brasilense can be distinguished from all other species in Suriname by its smaller size (forearm length less than 40 mm, greatest length of skull less than 21.0 mm). This species was often taken in association with secondary vegetation, or restricted forest, in savannah regions.

The two medium-sized species--carrikeri and schulzi--can be distinguished because the underparts of carrikeri are entirely white except on the chin and sides of the abdomen and in schulzi the dorsal surfaces of most membranes are covered with unique small wart-like granulations. Although the samples of these two species are small, it appears that specimens of T. carrikeri are slightly larger than specimens of T. schulzi. Both species were taken in dense lowland rainforest characterized by tall trees. The geographic distribution of T. schulzi is confined to the undisturbed forests of four nature preserves in central Suriname.