12 



A. geoffwyi: Tropical Mexice^ to W Ecuador (A. g. lasiopyga), central Colombia to central 

 Bolivia {A. g. peruana) Venezuela, Guayana, Trinidad, Grenada Islands, E Bolivia to 

 eastern Brazil {A. g. geoffwyi) 



A. latidens: N Venezuela to E Peru 



Hylonycteris 



H. undenvoodi: Western Mexico from Jalisco to Oaxaca {H. ii. minor); Veracruz to 



Panama, incl. Belize (//. ii. iinderwoodi). 

 Scleronycteris 



S. ega: Southern Venezuela, northwestern Brazil (Amazon region) 

 ChoeroniscHS 



C. godniani: W Mexico and northern fringe of South America to Surinam 



C. intermedins: Trinidad I., Guyana, Surinam, N Brazil and Peru (east of the Andes) 



C. minor. South American tropics from W Ecuador to the Amazon delta, north to 



E Venezuela and south to NW Bolivia 

 C. periosus: W Colombia (C. p. periosus), northwestern Venezuela (C. p. ponsi) 

 Choeronycteris 



C. mexicana: SW USA to Honduras incl. Tres Marias Islands 

 C. harrisoni: SW Mexico (Colima, Guerrero u. Michoacan) 



Habitat, roosting behaviour, migration 



Tlie ecology of bats is predominantly determined by two elements: finding food on one 

 hand and on the other - just as compelling - finding suitable day shelter. Thus, any 

 locality of collected material will only reveal half of the occupied habitat. An insight to 

 the ecological demands of a chiropteran species wiU only be gained by long-term field 

 observations or by comparative observations of captive animals in their roost and during 

 foraging. But the capturing data of most specimens allows - at least tentatively - 

 assessment to the habitat of the species. Accordingly, the members of some genera are 

 restricted to tropical ramforest {Choeroniscus, Hylonycteris, Lichonycteris), while others 

 occur almost everywhere {Anoiira, Glossophaga, Lonchophylla). Some genera 

 {Leptonycteris, Platalina and Choeronycteris) are adapted to arid areas, where they 

 predominantly feed on cactus flowers. 



These highly adapted flower visitors depend on pohen as a protein source all around the 

 year. Unless they cover larger distances they can only get it in the highly constant milieu 

 of the neotropical rainforest. This ecological request is mainly due to the fact that 

 hovering flight requires a relative high amount of energy hi food intake (v. Helversen & 

 Reyer 1984). One strategy to succeed with limited sources is outrurming intraspecific 

 competion - this will only work in low population densities and within large distribution 

 areas (e.g. Amazon rain forest). Here, most nectarivorous bats inhabit territories in small 

 family groups all tlie year roimd {Choeroniscus, Koepcke 1987). 



Tliere are, however, areas, where seasonal peaks of food supply determine the amount of 

 food available to the bats, requiring a quite different strategy. Thus Leptonycteris, though 

 liiglily specialized on blossom food, lives in large colonies - all tlie host plants of their 

 arid habitats usually bloom simultaneously, providing a rich food supply over a short tinie. 

 hi need of constant food supply, the anmials are forced to visit tlieir host species currently 

 flowering within various areas, and often cover considerable distances (Humphrey & 

 Bonaccorso 1979). Furthermore, climate changes require long migrations, as the bats are 



