In a small collection of mammals recently sent by Dr. G.F. Gaumer fromIzamal, Yucatan, to this Museum for identification, is a singlespecimen of a species of Adelonycteris, which appears to beundescribed. It may be called
Adelonycteris gaumeri, sp. nov.
Above dark brown, with an olivaceous wash, the fur beinguniform dark brown to the base tipped with a slight tinge ofolivaceous, the extreme tip slightly grayish in certainlights; below much lighter, the fur being dark brown basallyand broadly tipped with pale buffy gray; ears and membranesblack, naked, and with no trace of a whitish border. Ears ofmedium size, rather thin, evenly convex on the front border,slightly hollowed on the posterior border below the roundedposteriorly directed tip; tragus long and rather narrow,pointed, equal to half the height of the ear. Facesemi-nude, about as in A. fusca.
Measurements.—“Length, 95 mm.; expanse, 286; wing, 124;tail, 40”;[1] ear, 21; tragus, 11; fore arm, 39; thumb, 7;3d digit, 79 = phal. i, 37, phal. ii, 24; phal. iii, 11;phal. iv, 7; tibia, 70; foot, 8.
Skull.—Similar in a general way to that of A. fusca,but about one-half smaller. Middle inner upper incisorsconsiderably worn, and the ridges for muscular attachmentstrongly developed, indicating an old individual. Greatestlength (front base of incisors to end of crest), 18; mastoidbreadth, 8.3; zygomatic breadth, 10.1; interorbital breadth,4; length of molar-premolar series, 4.2; palatal length,5.3.
Type, No. 12753/11040, ♀ ad., Izamal,Yucatan; collected by Dr. George F. Gaumer, for whom thespecies is named.
In coloration Adelonycteris gaumeri resembles examples of A. fuscain immature dark pelage, but it differs from this species in thethinness of the ears, and in the greater relative length of thenarrower and more tapering tragus, and in its very much232 smaller size.In size it resembles both ‘Vesperugo’ propinquus Peters and V.(Marsipolæmus) albigularis Peters, respectively from Guatemala andMexico. The peculiar structure of the ears, to say nothing of thecoloration, in V. albigularis, render comparison with this speciesunnecessary. V. propinquus is described as reddish above, paler andmore reddish yellow below, and in this respect is widely differentfrom A. gaumeri. It has also a longer thumb and foot than A.gaumeri.
The type and only specimen of this species has been kindly presentedby Dr. Gaumer to this Museum, with other specimens of Yucatan mammals.
[1] Collector’s measurements from the fresh specimen; therest are from the dry skin.