Part 2

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.

Pteronotus suapurensis (J. A. Allen, 1904)

Specimens.--Chontales: Cuapa, 1. Matagalpa: 3 mi E San Ramón, 24. Zelaya: Cara de Mono, 25 m, 4.

This relatively poorly known monotypic species occurs from southern Veracruz to the Amazon Basin. It has been reported from several localities in Central America including one in Nicaragua (Goodwin, 1942a:88). Three pregnant females from near San Ramón (9 May) carried embryos that had crown-rump lengths of 27, 27, and 28 mm, and two netted on 24 April at Cara de Mono each had an embryo that measured 22 mm. All of our specimens are in bright pelage that is fulvous red in color.

Micronycteris megalotis mexicana Miller, 1898

Specimens.--Carazo: 3 km N, 4 km W Diriamba, 600 m, 5. Granada: Hda. Mecatepe [2 km N, 11.5 km E Nandaime], 5. Managua: 5 mi NW Managua, 1. Matagalpa: Río Viejo, 7 mi WNW Darío, 4; 11 mi SE Darío, 1. Zelaya: S end Isla del Maíz Grande, 9.

The individuals from Isla de Maíz Grande were shot on 30 June as they flew from small caves and crevices in rocky outcrops on the south end of the island. Of the three adult females obtained at that time, two were lactating; each was accompanied by a young, the forearms of which measured 19.7 (male) and 21.3 mm (female). Two adult males from Isla del Maíz Grande had testes 2 mm in length.

TABLE 1.--Selected measurements of adults of two subspecies of Micronycteris megalotis from Nicaragua. Superscript numbers indicate fewer specimens averaged than indicated in left-hand column.

Table Legend:

Col. A: Number of specimens averaged or catalogue number, and sex Col. B: Length of forearm Col. C: Greatest length of skull Col. D: Zygomatic breadth Col. E: Breadth of braincase Col. F: Length of maxillary toothrow

=================================================================== A B C D E F ------------------------------------------------------------------- Micronycteris megalotis mexicana, west-central Nicaragua

Average 8 35.4 19.5 9.5 8.0 7.5 (3, 5 [Female]) Minimum 33.0 18.8 9.1 7.7 7.3 Maximum 38.1 20.3 9.8 8.2 7.7

Isla del Maíz Grande, Nicaragua

Average 6 35.6 19.4 9.2 7.8 7.4 (3 , 3 [Female]) Minimum 34.5 19.1 9.0 7.7 7.3 Maximum 37.0 19.8 9.3 7.9 7.5

Micronycteris megalotis microtis, Greytown, Nicaragua (holotype)

USNM 16366/23364, 31.5 18.2 8.8 7.6 6.9

Río Coco, Nicaragua (AMNH)

Average 6 33.6 18.9 -- 7.5 7.1 (3 , 3 [Female]) Minimum 32.7 18.8 -- 7.4 7.0 Maximum 34.2 19.0 -- 7.6 7.2

Bonanza, Nicaragua

KU 96251, 32.3 18.4 8.8 7.6 7.0 -------------------------------------------------------------------

Specimens labeled with reference to Darío, Diriamba, and Managua.

Four of the five specimens taken northwest of Diriamba were shot from a daytime retreat in a culvert; the fifth was caught by hand as it attempted to fly out of a hollow, fallen tree. Two adult females captured on 31 March were pregnant, each carrying a single embryo (13 and 14 mm in crown-rump length), whereas two obtained on 14 August showed no sign of reproductive activity. An adult male, also taken on 14 August, had testes 2 mm in length. Of three additional adult females, one captured on 3 June was pregnant (embryo 21 mm in crown-rump length), whereas two obtained on 14 April evinced no gross reproductive activity.

The subspecies mexicana has not been reported previously from Nicaragua, although Gardner et al. (1970:715) recently extended its known distribution southward from Honduras (Goodwin, 1942c:124) and El Salvador (Felten, 1956:180) to west-central Costa Rica. In Nicaragua, as apparently in Costa Rica, mexicana occupies the Pacific versant, the Caribbean lowlands being inhabited by the smaller race, Micronycteris megalotis microtis Miller, 1898 (type locality, Greytown, Nicaragua--reported also from "Río Coco," Nicaragua, by J. A. Allen, 1910:110). Nicaraguan examples of M. m. mexicana are, on the average, considerably larger in cranial dimensions and length of forearm than are specimens of M. m. microtis (see Table 1). The series of microtis from "Río Coco," probably from the headwaters of that stream in the vicinity of San Juan de Río Coco and thus near the divide between Caribbean and Pacific drainages, is intermediate in size between the two subspecies and suggests intergradation between them. As noted also by Gardner et al. (1970:715), we find no differences in length of ear between microtis and mexicana (contrary to Miller's claim, in the original description, that microtis had noticeably smaller ears), nor do we note any consistent differences in color between the two races on the basis of the specimens at hand.