Rhynchonycteris naso (Wied)

VOUCHER MATERIAL: 4 females (AMNH *265985, *265988, *267373; MNHN *1995.844) and 6 males (AMNH *265981, *265986, *265987, *267372; MNHN *1995.845, *1995.846); see table 7 for measurements.

IDENTIFICATION: Sanborn (1937) and Jones and Hood (1993) discussed cranial and dental characters of Rhychonycteris naso, and Husson (1962, 1978) provided a detailed description and comparative measurements.

Measurements of specimens previously collected in French Guiana were reported by Brosset and Charles­Dominique (1990). No subspecies are currently recognized (Koopman, 1994).

Our voucher specimens conform to previous qualitative descriptions of Rhynchonycteris naso and measurements fall within the range of size variation previously report­ ed for the species. However, our morphometric data (table 7) somewhat exceed the range of size variation known from the Guianas, representing specimens both slightly smaller and slightly larger than those reported by Husson (1962, 1978) and Brosset and Charles­Dominique (1990).

FIELD OBSERVATIONS: We captured 10 individuals of Rhynchonycteris naso, all of which were found roosting over water in large (3–4 m in diameter) metal culverts or under concrete bridges. The five roosting groups we observed ranged in size from three to about nine individuals. One group of three bats consisted of two adult males and one adult female, and one group of about nine contained at least two adult males, but our information about the age and sex composition of the other groups is too incomplete to be informative.