Biological Observations on Anopheline Mosquitos in Korea, with Special Reference to Anopheles (Anopheles) Sinensis Wiedman

In Tansan and Wondang in 1960, and in Guidandong and Yongju-eup in 1961, routine entomological work was carried out according to the plan of operation for the ma1aria pre-eradication survey.

During the present work, six anopheline mosquito species were recorded as follows:

1. Anopheles (Anopheles) sinensis Wiedmann, 1828.

2. Anopheles (Anopheles) sineroides Yamada, 1925.

3. Anopheles (Anopheles) lesteri Baisas and Hu, 1936.

4. Anopheles (Anopheles) koreicus koreicus Yamada and Watanabe, 1918.

5. Anopheles (Anopheles) koreicus edwardsi Yamada, 1925, and,

6. Anopheles (Anopheles) lindesayijaponicus, Yamada, 1918.

A. sinensis is the most predominant species, although A. koreicus koreicus was also found to be predominant after A. sinensis in Guidandong (a mountainous area) A. sineroides is the next most predominant species after A. sinensis.

Anopheline mosquitos begin to appear from late April or May and disappear in October each year. The resting places for the anopheline mosquitos are mainly cow sheds and outdoors. The population density of A. sinensis in cow sheds shows a peak either in June or in July in most places with a second small peak in late August or in September.

Night biting habits appear to be active throughout the whole night but are more active from sunset to midnight.

Most of the anophelines caught appeared to be zoophilic; however, the results of precipitin tests for A. sinensis showed a likelihood that these are facul-tative anthropophilic.

Dissection of salivary glands in the present study of 2736 female A. sinensis mosquitos failed to show or to prove the presence of sporozoites, although sinensis is suspected as a potential of malaria.

The body weight, moisture and fat content in A. sinensis appeared to decrease in July from a high peak in June and then to increase again in September.

Insecticide susceptibility tests proved that the species was susceptible to DDT and Dieldrin in Guidandong and Yoju.

The bionomics of A. sineroides, A. koreicus koreicus, A. koreicus edwardsi, A. lesteri and A. lindesayi japonicus was discussed; the latter two species are probably the first to be recorded in Korea.

The mosquitos caught in hibernating places were found to be nulliparous and to have sperms in the spermathecae during the winter months. Anopheline hibernated probably in the adult stage.