This fish-eating species, first reported from Nicaragua by Davis et al. (1964:376), apparently occurs throughout Middle America, although known from the region by comparatively few records. We have 13 additional Nicaraguan specimens as listed above.
The two individuals (both females, one pregnant with an embryo that measured 20 mm) from Potosí were caught on 6 March in a mist net set over a large pool in a shallow estuarine stream; the mouth of the stream opened into the Gulf of Fonseca approximately 200 yards below our netting site. Other individuals of this species were observed as they foraged over large pools formed at high tide near the mouth of the stream. Our other specimens were caught in mist nets set over fresh water streams near Lake Nicaragua or along the shores of the lake. A female from near Alta Gracia, caught on 27 March, carried a single embryo that measured 41 mm, whereas one from Finca Amayo was lactating on 25 June. Four males taken on Isla de Ometepe in late March and early April had a mean testicular length of 9.5 (8-10) mm.
Pteronotus davyi fulvus (Thomas, 1892)
Specimens.—Chontales: Cuapa, 4. Matagalpa: 3 mi E San Ramón, 126.
This small naked-backed bat has not been reported previously from Nicaragua. Autopsy of seven females collected on 9 May near San Ramón revealed that four were pregnant, each with a single embryo—average crown-rump length 25.0 (21-29) mm.
The distribution of P. davyi is poorly known in much of Central America. The species was reported only recently from Costa Rica (Starrett and Casebeer, 1968:8) and is unknown from Panamá. We assign our specimens tentatively to the subspecies fulvus on geographic grounds.
Pteronotus parnellii fuscus (J. A. Allen, 1911)
Specimens.—Boaco: Santa Rosa, 17 km N, 15 km E Boaco, 300 m, 1; Los Cocos, 14 km S Boaco, 220 m, 1. Chinandega: 6.5 km N, 1 km E Cosigüina, 10 m, 1. Zelaya: Bonanza, 850 ft, 1; 2 mi SW Bonanza, 600 ft, 1; S side Río Mico, El Recreo, 25 m, 1; Cara de Mono, 50 m, 4.
Although this species is widespread in Middle America, it has been known previously from Nicaragua only by a specimen from "Chontales" (Miller, 1902:402). All of our specimens were captured in mist nets. Two adult females (one taken on 28 February and the other on 8 March) each carried a single embryo (13 and 18 mm in crown-rump length, respectively); a female taken in April was lactating and had a flaccid uterus suggesting relatively recent parturition. Adult females captured in the months of June, July, and August evidenced no sign of reproductive activity. Two of these were in dark, fresh pelage, but one captured on 24 June and another on 28 July were molting. In both individuals, active molt evidently had slowed or subsided and remnants of the old pelage (rich ochraceous orange) were confined to a narrow strip at the lateral edges of the body.
We tentatively apply the subspecies name fuscus to our Nicaraguan bats on geographic grounds; one of us (Smith) currently is investigating geographic variation in the genus Pteronotus.