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Developmental Cycle

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Larva

The first immature stage, the larvae (which are often called seed ticks), only have six legs.

Unfed larvae hatch from an egg batch of some hundreds (Argasidae, soft ticks) to several thousands (Ixodidae, hard ticks).

Ixodid larvae climb the vegetation or other surfaces in their natural environment and commence questing.
Alternatively, larvae may enter diapause and over winter (or, rarely over summer) until appropriate environmental changes terminate that state.

Argasid hungry larvae attack vertebrate hosts inhabiting the nest, burrow, or other niche environment.
Almost all argasid ticks have a multi-host feeding pattern (Hoogstraal and Aeschlimann, 1982). In the majority of species, i.e., those that feed on mammals and birds (but excluding bats), larvae seek hosts, feed rapidly (15-30 minutes) and drop to molt in the sand, duff or cracks and crevices of the natural habitat.

Because of the difficulty of finding a suitable host, larvae can withstand long periods without feeding.

Following host contact, larvae attach, insert their mouthparts into the host skin and feed.

Engorgement is completed within several days, depending upon the species and host.

In some argasid species, larvae do not feed but molt directly in the first nymphal stage (N2) and the N1 is the non-feeding stage.

The engorged larva molts into an unfed eight-legged nymph.

   

Further information

  • Hoogstraal H, Aeschlimann A: Tick-host specificity. Bull Soc Entomol Suisse. 1982, 55, 5-32
  • Sonenshine DE: Biology of Ticks. Part 1, 1991, Oxford University Press, New York

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