During recent entomological surveys a tremendous increase in numbers of Anopheles nuneztovari Gabaldon has been observed in the interior of Surinam. The construction of the Afobaka dam, which gave rise to the Brokopondo storage lake, was the main factor responsible for this increase. The scarcity of An. darlingi, the principal vector of Plasmodium falciparum in Surinam, and the failure to capture this species during recent epidemics of malignant malaria in certain areas where An. nuneztovari abound, indicate that the latter might be involved in active transmission of the parasite. Breeding experiments with An. nuneztovari showed a duration of 1 day for the egg stage, 7 days for the larval stages and 1 day for the pupal stage. The gonotrophic cycles may last 4 days each, except the 1st which takes 5 days. The daily biting activity pattern of this species show a unimodal pattern with a sharp peak at 6:00-7:00 pm. The maximum and minimum parous rates which may be reached over a longer period of time are 0.69 and 0.14 respectively, the mean being 0.34. This rather high parous rate indicates that this species may well act as a good vector of pathogens, because it feeds readily on man and occurs in large numbers during certain periods of the year. It appears that the population of An. nuneztovari at Brownsweg is fully susceptible to DDT, dieldrin and malathion.