92 



NORTH AMERICAN FAUNA 75 



Myotis nigricans 

 Black Myotis 



The black myotis is distributed from Tamaulipas, Mexico, to Argentina 

 (Fig. 71). The nominate subspecies, Myotis nigricans nigricans, is found throughout 

 Central America. 



This species is known from almost all vegetation types within its broad range. 

 In Costa Rica it is found from sea level to above 3,000 m. Black myotis roost in 

 buildings, caves, tunnels, and hollow trees. The reproductive cycle is one of seasonal 

 polyestry with a short diapause during the end of the rainy season (Wilson 1971b). 

 The biology of black myotis was summarized by Wilson and LaVal (1974) and 

 Wilson (1983b). 



Goodwin (1946) reported black myotis from several Costa Rican localities, 

 and subsequent workers have found this species occurring in most areas of the 

 country. LaVal took 14 during his study at La Selva (LaVal and Fitch 1977). Our 

 specimens from Parque Nacional Braulio Carrillo were caught in mist nets set over 

 small streams near large tracts of primary forest. We obtained two species of bat 

 flies on M. nigricans: Anatrichobius scorzai (1 female) and Basilia sp. (4 males, 

 3 females). 



Specimens examined (19)— Puerto Viejo de Sarapiqm [2 males, 1 female, 

 LACM]; Finca La Selva, 3 km S of Puerto Viejo, 70 m [1 female, KU]; 5.7 mi 

 S of Puerto Viejo [1 male, LACM]; 1 1 km S, 4.5 km W of Puerto Viejo, 270 m 

 [1 male, USNM]; 1 km S, 11.5 km E of San Miguel, 680 m [1 male, USNM]; 

 Volcan Barva, 3.2 km S of Los Cartagos, ca. 1,800 m [12, LACM]. 



Myotis oxyotus 

 Montane Myotis 



Montane myotis reach their northern limit in Costa Rica; the species extends 

 south to Bolivia (Fig. 72). The Central American subspecies (LaVal 1973a) is Myotis 

 oxyotus gardneri. 



In Central America, the montane myotis is known only from highland areas 

 of the Cordillera Talamanca in Panama and Costa Rica, and the Cordillera Tilaran 

 of Costa Rica. The Vara Blanca specimen represents the northeasternmost record 

 of the species. The habitat there is moist oak forests and cloud forests. We have 

 also taken this species on several occasions in the Monteverde region. Montane 

 myotis are insectivorous, but details of the food habits are unknown. The few records 

 of reproductive activity (Gardner et al. 1970) suggest a monestrous cycle, with 

 young born in summer. 



The first Costa Rican records came from near Villa Mills on Cerro de la Muerte 

 (Starrett and Casebeer 1968). Gardner et al. (1970) collected specimens from San 

 Jose and Cartago Provinces in addition to the single male from Vara Blanca in 

 Heredia Province. 



Specimen examined (1)— Vara Blanca, 1,800 m [1 male, LSUMZ]. 



