Otobius megnini: Spinose ear tick.

General Description: Soft tick. Adults are shaped somewhat like a fiddle and are about 1 cm. Long, but are not parasitic. Larvae and nymphs are responsible for damage. Larvae are nearly spherical. Nymphs are bluish-grey, roughly the shape of a violin body, with numerous, pale yellow, spine-like processes. Nymphs are 8 to 10mm long.

Life Cycle: Typical tick life cycle except that adults do not live or feed on the host. Females live in hidden, sheltered areas and lay eggs for up to six months after breeding.

Location: Inside ears.

Geographical Distribution: North, Central, and South America, South Africa, and Hawaii, especially in warm areas.

Significance: The spinose ear tick is a serious threat to sheep. Very heavy infestations can occur and cause much debilitation.

Effect on Host: Damage caused by the blood-sucking larvae and nymphs of Otobius is similar to disease of adult hard ticks. Depressed appetite and restlessness in sheep, with decreased gains; possibly weakness and anaemia. A waxy exudate is often present in ears.

Diagnostic Information: Larvae and nymphs are found in the ears.

Control: Sheep should be treated with insecticides, as should yards or pens where animals live, in order to kill adult ticks which live and breed in these areas.