Eumops Dabbenei - Dabbene’s Mastiff Bat​

Physical Description:

Dabbene’s Mastiff Bat is a large bat.  The body of E. dabbenei is thick, with short forearms in proportion to its bulky body and broad head.  The dorsal coloration is an ocraceous chestnut with the bases of the hairs paler; ventrally paler, with broad ears not extending past the tip of the nose when projected outward.  The lamboid crests are strongly developed and the sagital crest is less developed. The ears are united and the lips are smooth.  The pad of the thumb is triangular and the tail is very thick (Harrison et al. 1979, Meyers and Wetzel 1983, Nabong 2002 http://animaldiversity.ummz.umich.edu/site/accounts/information/Eumops_dabbenei.html).  Total length, 165; tail 56-59; ear 25-27; forearm 78-85; weight 76, dental formula 1/2 1/1 2/2 3/3=30 (Barquez et al. 1993).

Distribution:

E. dabbenei is known from Columbia (Magdalena River Valley), Venezuela, Central Paraguay and northern Argentina (Chaco, Tucuman and Santa Fe Provinces).  The terrestrial biomes include forest, rainforest, and scrub forest.  E. dabbenei is found in only 2 of Paraguay’s 7 biomes.  It is found in western Paraguay in the Alto Chaco region and in south-eastern Paraguay in the Neembucu region (Willig et al. 2000). 

Ontogeny and Reproduction:

Females have one litter per year although it is possible for them to have two.  Males have a throat sac that swells with pheromone laden musk during the breeding season (Novak 1999; Hill and Smith 1984).  The secretions from the throat sac stain and mat the fur of the neck (Ibanez 1979).

Ecology and Behavior:

Little is known about the social behavior of E. dabbenei.  These bats feed by catching insects in flight.  This behavior is known as ‘aerial insectivory’.  Evidence indicates that fat metabolism is of primary importance as opposed to protein or carbohydrate metabolism.  The habitats preferred by E. dabbenei are Neotropical and Tropical.  Distribution occurs in dryer habitats of low growing vegetation, with islands of forests and gallery forests.  Populations also occur in premontane and humid forests (Ochoa and Ibanez 1985). 

In Neotropical areas, this species tends to roost in the holes of trees or buildings.

In tropical, forested areas E. dabbenei roost primarily inside hollow trees in Columbia, Venezuela, Paraguay and Argentina (Meyers and Wetzel 1983, Barquez et al 1993, Nowak 1999, Fioramonti 2001).  The full range of habitats available is poorly understood.  This species is a secondary or tertiary consumer.  It eats either herbivores or carnivores that prey on herbivores.  They prey primarily on airborne insects (Findley 1993).  The abundance of this species is poorly understood and is believed to be rare throughout its range.  There is no special protected status for E. dabbenei at this time (Barquez et al. 1993).

Remarks:

E. dabbenei can be easily distinguished from E. perotis by its shorter ears that extend beyond the snout when projected forward, a pointed tragus, and more massive skull.  Because of its large size, it can only be confused with E. perotis (Harrison et al. 1979, Meyers and Wetzel 1983, Barquez 1993).

Literature Cited:

Barquez, R., N.P. Giannini, M.A. Mares.  1993.  Guide to the Bats of Argentina.  Oklahoma Museum of Natural History.

Findley, J.  1993. Bats:  A Community Perspective.  Cambridge:  Cambridge University Press.

Fioramonti, E.  “Museo de la Provencia de Santa Fe (Argentina)” (On-line).  Accessed October 21, 2004 at http://santafe.gov.ar/cultura/museos/mamifero.htm.

Harrison, D., N. Pendleton, G. Harrison.  1979.  Eumops dabbenei Thomas 1914 (Chiroptera:  Molossidae), a free tailed bat new to the fauna of Paraguay.  Mammalia, 43(2): 251-252.

Hill, J., J. Smith.  1984.  Bats:  A Natural History.  London:  British Museum (Natural History).

McWilliams, L. A., T. L. Best, J. L. Hunt, K. G. Smith.  2002.  Mammalian Species.  American Society of Mammologists.

Nabong, M. 2002. "Eumops dabbenei" (On-line), Animal Diversity Web. Accessed October 19, 2004 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Eumops_dabbenei.html.

Nowak, R.  1999.  Walkers Mammals of the World.  Baltimore, MD:  The Johns Hopkins University Press.

Ochoa G., J., and C. Ibanez.  1985.  Distributional status of some bats from Venezuela.  Mammalia 49:65-73.

Redford, K. H., and J. F. Eisenberg.Eisenberg.  1992.  Mammals of the Neotropics.  The Southern Cone:  Chile, Argentina, Uruguay, Paraguay.  University of Chicago Press, Illinois 2:1-430.

Willig, M. R.  S. J. Presley, R. D. Owen, and C. Lopez-Gonzalez.  2000.  Composition and structure of bat assemblages in Paraguay:  A subtropical-temperate interface.  Journal of Mammology, 81(2)386-401.

Reference written by Serene Granstrom, Biol 378 (Mammalogy), University of Wisconsin – Stevens Point:  Edited by Christopher Luddington. Page last updated 02-17-05.