Diaemus youngi (Jentink)

Simmons, Nancy B. & Voss, Robert S., 1998, The mammals of Paracou, French Guiana, a Neotropical lowland rainforest fauna. Part 1, Bats, Bulletin of the American Museum of Natural History 237, pp. 1-219 : 47

Diaemus youngi (Jentink)

VOUCHER MATERIAL: 1 female (AMNH *268571) and 2 males (AMNH *266347; MNHN *1995.984); see table 11 for measurements.

IDENTIFICATION: Descriptions and measurements of Diaemus youngi appear in Husson (1962, 1978), Swanepoel and Genoways (1979), Hall (1981), Koopman (1988), and Greenhall and Schutt (1996). Some authors place D. youngi in the genus Desmodus (e.g., Handley, 1976; Emmons, 1990), but we retain Diaemus as a distinct genus following Cabrera (1958), Husson (1962, 1978), Jones and Carter (1976), Hall (1981), Koopman (1993, 1994), and Greenhall and Schutt (1996). Although Thomas (1928c) named D. y. cypselinus based on material from Peru, Husson (1962: 198) noted that cypselinus was probably ‘‘not subspecifically different from the typical form.’’ Subspecies of Diaemus youngi have not been recognized by most authors (e.g., Cabrera, 1958; Koopman, 1993, 1994; Greenhall and Schutt, 1996).

Our material of Diaemus youngi from Paracou conforms closely with previous qualitative descriptions of the species. Although forearm and cranial dimensions of our specimens are considerably smaller than those reported for specimens from Mexico, Costa Rica, Peru, Venezuela, and Trinidad, they are only slightly smaller than those previously reported from the Guianas (Thomas, 1928b; Goodwin and Greenhall, 1961; Husson, 1962; Hall, 1981; Brosset and Charles­Dominique, 1990; Greenhall and Schutt, 1996). The significance of this variation is not clear, but we note that the Guyanese holotype of D. youngi (RNH 12088) is one of the smallest specimens hitherto reported in the literature ( Husson, 1962; Carter and Dolan, 1978). Thus, if subspecies are recognized in some future revisionary study, our material would presumably be referred to the nominate form.

FIELD OBSERVATIONS: Two of the three Diaemus youngi we captured at Paracou were taken in ground­level mistnets, one in well­drained primary forest, and the other in a manmade clearing. The third specimen was captured in a mistnet suspended 17–20 m above a narrow dirt road.