Species Otobius megnini - spinose ear tick

western and southwestern United States, south to Argentina, Brazil, and Chile; introduced to India, Australia, and South Africa. (1)

Larvae and nymphs live within the ear canal of the mammalian host. Adults are non-parasitic.

Documented hosts include: cattle, cats, sheep, horses and other equines, goats, swine, coyotes, deer, bighorn sheep, cottontail rabbits, jackrabbit, ostrich, javelina, and pronghorn; rare zoonotic infection in humans. Most common in arid regions. (1)

Blood of the mammalian host (see also habitat, above).

Eggs of Otobius megnini are laid on or near the ground for as long as 6 months. They hatch in 18 days or more. The larvae then crawl up vegetation, fence posts and feed bunks to await hosts. Unfed larvae may live off the host for more than 2 months. If they find host, they locate in the ears where they engorge for 5 to 10 days. The larvae molt to the nymphal stage in the ears. Here they engorge for about a month. However, the nymphs may remain in the ear for as long as 7 months. When ready to molt, they crawl out of the ears to the ground where they molt to adults. This species is a one-host tick. (1)