Observations on the subgenus Argas (Ixodoidea: argasidae, Argas). 8. The life cycle of A. (A.) hermanni.

Abstract

Argas (A.) hermanni Audouin was reared on domestic pigeons and held at 28–29°C and 75% RH. The life cycle is completed in a maximum period of 161 days. The egg incubation period is 20 days. Most larvae are ready to feed 6 days after hatching; they attach for 7 days and molt to N1 9 days after dropping from the host. Most N1 and N2 are ready to feed when 12–150 and 3–120 days old, respectively. After feeding, N1 molt to N2 in 14 days and N2 to adults in 25 days. Most males and females are ready to feed when 15–180 and 11–150 days old, respectively. The 1st preoviposition period (11 days) is longer than the 2nd (8.5 days) or 3rd (8 days) periods. Females deposit 189–219 eggs during a 15 to 19-day period; differences between egg numbers and oviposition periods after 1st, 2nd, and 3rd blood meals are insignificant. The female deposits 6–8 egg batches and may produce 600–800 adults per lifespan. There is no ovarian diapause under the experimental conditions. There may be 2–5 generations each year. The high reproduction rate and the survival capacity of unfed ticks are discussed in relation to transstadial passage of pathogens. This species occurs in nature from northwest Africa to Nepal and is infected by Grand Arbaud, Chenuda, Abu Hammad, Royal Farm, West Nile, and Quaranfil viruses, and by avian spirochetes ( Borrelia anserina ).