Mammalia , Chiroptera , Phyllostomidae , Diaemus youngi : First record for the state of Bahia , northeastern Brazil

Diaemus youngi is one of the three species of extant Neotropical hematophagous bats (Greenhall and Schutt Jr. 1996). Morphologically, it differs from the other two vampires in the lack of a calcaneum and a tail, and it also has white wing tips (Nowak 1994). Both sexes of this species possess cup-shaped scent glands located bilaterally inside the mouth, which emit an offensive odor (Greenhall and Schutt Jr. 1996). Its diet comprises mostly avian blood (Bredt et al. 1998).


Fábio C. Falcão
Instituto Dríades.Rua Nossa Senhora das Graças 325.CEP Itabuna,BA, Diaemus youngi is one of the three species of extant Neotropical hematophagous bats (Greenhall and Schutt Jr. 1996).Morphologically, it differs from the other two vampires in the lack of a calcaneum and a tail, and it also has white wing tips (Nowak 1994).Both sexes of this species possess cup-shaped scent glands located bilaterally inside the mouth, which emit an offensive odor (Greenhall and Schutt Jr. 1996).Its diet comprises mostly avian blood (Bredt et al. 1998).
The geographic distribution of the white-winged vampire bat ranges from northeastern Mexico to northern Argentina (Greenhall and Schutt Jr. 1996).The species has been recorded in all Brazilian biomes (Marinho-Filho and Sazima 1998), although there is an expressive gap of records in northeastern Brazil.Recently, Aguiar et al. (2006) reported the occurrence of this species in the Cerrado of Central Brazil and summarized the previous occurrence of Diaemus youngi in 12 Brazilian states.In the northeastern region, the species was recorded only to the states of Piauí, Pernambuco, and Alagoas.The present study reports the first occurrence of D. youngi in the state of Bahia, filling this gap in its geographical distribution (Figure 1).
A survey of bats was conducted in the counties of Canavieiras from 18 to 22 October 2005, and Mascote from 9 to 13 January 2006.The survey involved sporadic searches for diurnal roosts and captures of bats using mist nets (9 x 3 m) placed at ground level.The total netting effort was calculated following Straube and Bianconi (2002) as the product of the sampling area (216 m 2 ), the number of sampling hours per night (5), and the total number of netting nights (10), which amounted to 10,800 m 2 .h,and resulted in 128 captures of 15 bat species.One adult male of D. youngi was collected at Fazenda São José in the municipality of Mascote (15º34'05" S, 39º17'07" W) on 12 January 2006, in the riparian forest on the left bank of the Jequitinhonha River (Figure 2).
The individual captured was measured with a Mitutoyo Vernier caliper (150 mm ± 0.01) and weighed using a Pesola scale (100 g ± 0.5).In the laboratory the specimen was prepared in alcohol 70 % and deposited in the Alexandre Rodrigues Collection (DE606) at the Universidade Estadual de Santa Cruz, Ilhéus -Bahia.The specimen was sexually active, its forearm was 54.9 mm long, and its body mass was 45 g.Although these values are similar to previous reports (Nowak 1994;Bredt et al. 1998;Eisenberg and Redford 1999), they are considerably higher than those reported for specimens from French Guiana (Simmons and Voss 1996), and slightly higher than those reported from Bolivia, Central Brazil, Venezuela and Ecuador (Anderson 1997;Aguiar 2006;Greenhall and Schutt Jr. 1996;Pinto et al. 2007).
The occurrence of the white-winged vampire bat at Fazenda São José could be explained by the presence of poultry there, a common food source.Due to its rarity in the region and the fact that D. youngi feeds preferentially on birds (therefore it has a small role in the cycle of rabies), this species should not be considered in control programs of vampire bats, as previously suggested (Aguiar and Taddei 1995;Bredt et al. 1998).
The southern region of Bahia has been extensively sampled for bats so this single record obtained only now suggests that the species is rare in the region.A recent compilation of bat species occurring in southern Bahia (Faria et al. 2006), together with other bat surveys by the same author (unpublished data) totals approximately 7,200 captures of 60 bat species besides D. youngi.The capture of this individual of D. youngi increases to 79 the number of bat species in the state of Bahia.
Diaemus youngi is considered threatened of extinction in the states of Paraná (Margarido and Braga 2004) and Rio de Janeiro (Bergallo et al. 2000), and it should be considered in the red list of Bahia for its presumed low abundance.

Figure 1 .
Figure 1.Localities where Diaemus youngi has been recorded ( ) and the new record for the state of Bahia, northeastern Brazil ( ).Map adapted from Aguiar et al. (2006).