Biology of Anopheles (Kerteszia) neivai H., D. & K., 1913 (Diptera: Culicidae) on the Pacific coast of Colombia: I. Fluctuation of larval population and characteristics of the breeding places

Abstract

The fluctuation of the larval population and characteristics of the breeding places of Anopheles (Kerteszia) neivai were studied in the village of Charambirá, Istmina county, Department of Chocó. This mosquito species is considered to be the malaria vector in this region of the Pacific coast of Colombia. The vegetation in the vicinity of the town was classified in three strata according to foliage coverage, and 100 m² quadrants were set up for sampling epiphytic plants of the Bromeliaceae family, which serve as breeding sites for this anopheline. Data corresponding to height, temperature, pH and water volume were taken for each bromeliad plant studied. The largest number of larvae were found in the mangrove forest (stratum 1) below a height of 4 m, although no significant evidence was found for vertical stratification of larvae below a height of 8 m. A positive linear correlation was found between the water volume and the number of larvae of A. neivai observed in each bromeliad. In addition a direct relation was found between cumulative monthly rainfall and the fluctuation of the larval population. The greatest larval indices were found from March to April and July to August. Larval mortality was high in the first instar (43.5%) and only 23.7% survive up to the fourth instar.