Culicidae, province of Misiones, northeastern Argentina

: We present a preliminary list of the Culicidae species collected in seven localities at the province of Misiones, Argentina, since the mosquito fauna of this region is poorly known. Mosquito sampling was carried out during spring-summer, between August 2006 and January 2007, the months of highest abundance of these insects. Collection of specimens was made with a CDC-like trap (Center for Disease Control and Prevention) in peri-urban zones. Sixty-five species were identified. The geographic distribution of Anopheles extended.


Introduction
The province of Misiones has a surface of 30,000 km 2 and is located between Paraguay and Brazil; it comprises part of the phytogeographic region of the semi-deciduous Atlantic forest in its northern portion and the southernmost area of the Distrito de los Campos. Mean temperatures range from 15 °C in winter to 26 °C in summer, with a mean annual rainfall of 1,800 mm. The remainder of the interior Atlantic forest was recently estimated as 41-55 % of the original area (between 11,000 km 2 to 17,000 km 2 ). This environment is a moderator of the climate, preserving a high level of humidity in the atmosphere and influencing high biodiversity in the flora, thus favouring the existence of a great diversity of animal species (Giraudo et al. 2003).
With the exception of the city of Posadas (Figure 1), all other collection sites in this study were within the area bound on the east by the Parque Estadual do Turvo, state of Rio Grande do Sul, Brazil, and in the north by the Parque Estadual Foz do Iguaçu, state of Paraná, Brazil, a region with the lowest anthropic degradation within the geographic area considered (Giraudo et al. 2003).
At present, about 3,622 species of mosquitoes are known in the World (Harbach and Kitching 1998;W.R.B.U. 2008). Until now, 226 (6.23 %) of them have been recorded in Argentina, of which 165 were found in the province of Misiones (Rossi et al. 2006). Many of Abstract: We present a preliminary list of the Culicidae species collected in seven localities at the province of Misiones, Argentina, since the mosquito fauna of this region is poorly known. Mosquito sampling was carried out during springsummer, between August 2006 and January 2007, the months of highest abundance of these insects. Collection of specimens was made with a CDC-like trap (Center for Disease Control and Prevention) in peri-urban zones. Sixty-five species were identified. The geographic distribution of Anopheles darlingi, Uranotaenia davisi and Howardina fulvithorax is extended.

Results and Discussion
More than 2,000 specimens were collected, 1,702 were identified (1,656 females and 46 males), corresponding to 65 known species within 18 genera (Table 2); the remaining specimens could not be identified because of the damage produced by the trap. The most diverse tribe was Aedini (21 species) followed by Sabethini (17 species) and Culicini (15 species).
Uranotaenia davisi was collected in December 2006 and January 2007 in the city of El Soberbio. This species was previously reported from the province of Formosa, Argentina, by Duret (1950). Howardina fulvithorax was also collected in Eldorado. This is the first report for both species in Misiones.
This preliminary study on the richness of mosquito species carried out during six months, mainly in eastern localities of Misiones, contributes to the knowledge of the mosquito fauna in densely inhabited peri-urban zones. Several species collected during this work are indicated as vectors of infectious agents in the Neotropical region (Table 2); however, there are not enough records in Argentina about the possibility that all these mosquitoes were vectors in the country.
Anopheles albitarsis s.l. is considered a complex of species (Albitarsis Complex), being collected in the sampling area with An. deaneorum (Rosa Freitas 1989). Both species can only be reliably identified by means of the clipeal setae in the head of the fourth-instar larva. The other species of the complex have not been mentioned in the area and their identification can only be done through other technical methods, such as molecular DNA analysis (Wilkerson et al. 1995). Anopheles albitarsis is considered a secondary vector of malaria in Argentina, while An. darlingi is the principal vector of the disease, at least in the north-eastern area of the Country (Bejarano 1960).
Anopheles darlingi is considered the most efficient vector of malaria in the Amazon basin and part of South America (Rubio-Palis and Zimmerman 1997; Rossi and Almirón 2004). The previous record of this species in the province of Misiones was from the Corpus locality (27°7'04" S, 55°32'34" W), near the Paraná River from a single badly preserved mosquito (Tricio et al. 2002). In the present   Figure 1; ♀/♂ = number of females and males specimens collected; * = species indicated as vectors of infectious agents in the Neotropical region.  et al. 1992). Stegomyia aegypti is vector of Dengue viruses in north-western and northeastern Argentina (Avilés et al. 1999). The first report of West Nile virus (WNV) in birds in Argentina was reported in 2004 (Díaz et al. 2008), and its isolation from equines in 2006 (Morales et al. 2006), Culex pipiens quinquefasciatus possibly being the vector in our Country as in other parts of the World.
Another Flavivirus, St. Louis Encephalitis virus (SLE) is transmitted by Cx. pipiens quinquefasciatus in Argentina (Mitchell et al. 1980;Contigiani and Spinsanti 2002;Diaz et al. 2003). According to Bejarano (1959a;, Haemagogus leucocelaenus could be vector of Yellow Fever virus (YF). Recently, Vasconcelos et al. (2003) reported the detection of YF antigen by immunohistochemistry in the liver samples of dead monkeys from the municipalities of Santo Antonio das Garruchos and Missfies, state of Rio Grande do Sul, Brazil. Unfortunately, there are no data in Argentina on mosquitoes that were responsible for the human cases of Yellow Fever in the rural areas of the municipalities of San Vicente and Eldorado in province of Misiones, reported during April 2008.
We would emphasize the presence of the principal vectors of Yellow Fever or Dengue viruses, i.e., Haemagogus leucocelaenus, Stegomyia aegypti and Stegomyia albopicta in the province. The last species can be found in wild, rural, urban and peri-urban environments and could connect the selvatic and urban cycles of the Yellow Fever (Consoli and Lourenço-de-Oliveira 1994). In this framework, the presence of these vectors deserves major attention by sanitary authorities.