We studied the distribution and diversity of Anopheles species in 123 counties (municipalities) in the State of Maranhão, Brazil. The basic method consisted of capturing female specimens inside and around human dwellings between 6 PM and 6 AM from January 1992 to December 2001. A total of 84,467 specimens belonging to 24 species were captured, with a predominance of A. triannulatus sensu lato (20,788), A. darlingi (19,083), A. nuneztovari (16,884), A. albitarsis s.l. (14,352), A. aquasalis (8.202), and A. evansae (2,885). The other 18 species together accounted for only 2.7% of the total. The species found in the most counties were A. albitarsis s.l. (109 counties), A. triannulatus s.l. (106), A. nuneztovari (93), A. darlingi (87), and A. evansae (64). The richness and wide distribution of anopheline species in Maranhão agree with the State's geographic position among Brazil's macro-regions, resulting in a mixed fauna with representative elements from these regions.
Anopheles; Malaria; Demography
