Publication Date

Summer 2010

Degree Type


Degree Name

Master of Science (MS)


Biological Sciences


Elizabeth M. McGee


Hipposboscidae, host-parasite ecology, Allobosca crassipes, Madagascar, stable isotopes

Subject Areas

Biology, Entomology


The louse fly, Allobosca crassipes (Diptera: Hippoboscidae), is an obligate ectoparasite exclusive to lemurs in Madagascar. Research in Ranomafana National Park (RNP) in southeastern Madagascar has resulted in the identification of a new association of this fly with the black and white ruffed lemur, Varecia variegata variegata, and a confirmed association with Milne-Edwards' sifaka, Propithecus edwardsi. Previous descriptions of A. crassipes were based on only a few specimens, and the type specimen is presumed destroyed. The specimens of A. crassipes collected by SJSU in 2000-2001 provide the largest collection available for the purpose of describing this species.

Habitat disturbance is a major threat to the biodiversity of RNP and is predicted to affect parasite-host interactions. Disturbance has changed the behavior of the lemur hosts, which has indirectly affected the parasites. A. crassipes is found on several lemur species that rarely interact, but its low host specificity is an enigma since it is wingless as an adult. Disturbance may, however, indirectly contribute to low host specificity by forcing proximity and increasing interaction between host species. Further evidence of disturbance is seen in the isotopic composition of A. crassipes. A. crassipes-parasitizing lemurs inhabiting disturbed forests are significantly nitrogen depleted (as are their hosts) vs. those inhabiting undisturbed forests. These data further validate stable isotope ecology as a means of identifying ecosystem-wide habitat disturbance in rainforests.