BIOLOGY OF HAEMAPHYSALIS HYSTRICIS SUPINO

Haemaphysalis hystricis has been reported from Yunnan, Guangdong, Fujian and Taiwan Provinces. This tick is a forest-inhabiting species parasitizing on wild boar, porcupine, mantjac, dog, buffalo, etc. In June, 1978, eight larvae were collected from a bird, Centropus sinensis (Stephens), for the first time in Heyuan County, Guangdong Province. Published records hold that this tick Is active from March to August, and in November and December; but we have collected it in October for many times.The tick was reared at variable temperature, about 90% R. H., feeding on rabbits and white mice. Female-adults feeding on rabbits for 6 to 12 days (usually 9 days) had body weights ranging from 114 to 365 mg (208.3 mg on average), i.e., a nearly 80 time increase during the feeding stage. The preoviposition period was 4 to 12 days in June and July arid 22 to 34 days in November, The oviposition period lasted for .8 to 24 days in. summer, and 18 to 36 days in winter when 558 to 5330 eggs (about 300 eggs on average) per female were laid. The peak of oviposition appeared 3 to 5 days after oviposition began. A positive linear correlation occurred between the body weight of the fed female and the total number of eggs laid (r=0.058, P 0.01). A newly laid egg weighed 0.047 mg. The female survived from 1 to 10 days (usually 4 to 5 days) after completion of egg laying. The egg stage varied from 23 to 31 days in summer and from 50 to 74 days in winter. The larval stage lasted: for 8 to 15 days in summer and 22 to 30 days in winter. The larvae imbibed the blood of the host for 3 to 5 days; during this period their body weights increased for about 8 times. The transformation of engorged larvae into nymphs was accomplished in 10 to 14 days in August and September and 25 to 27 days -in January and February. The feeding of the nymphs lasted for 2 to 6 days when their body weights increased for about 24 times. Moulting of the nym-phs into the adults occurred 20 to 24 days in September. The ratio of the male to the female was 1:1.04.Under the laboratory conditions the minimal and maximal durations to complete the life cycle of this tick were 92 and 268 days respectively. The larvae can survive up to 389 days and the nymphs to 297 days. The adults may live for about two years.