Ticks in the genus Ixodes are easily recognized by the position of the anal groove, which lies in front of the anus and extends from one side of the body to the other.
There are 34 species of ticks in the genus Ixodes in the United States, more than in any other genus. Male specimens have a complicated arrangement of plates on the ventral side of the abdomen. Most species have enlarged club-like palps.
The black-legged tick, Ixodes scapularis
Commonly Carry: Lyme disease, human anaplasmosis, or babesiosis.
Markings: an adult female black-legged tick is red and dark brown, while an adult male black-legged tick is smaller and dark in color
Where Found: occurs in the eastern half of the United States.
Common Hosts:, Male and female specimens are frequently found mating on deer, dogs and other large mammals in the fall and winter. This species will also feed on man and birds.
The Pacific tick, Ixodes pacificus
Is the western counterpart of I. scapularis, and both species are related to the castor-bean tick of the Old World, Ixodes pacificus.
Commonly Carry: Anaplasmosis and Lyme Disease
Where Found: Western Black-legged ticks are found mostly in the Western US as shown by the purple on the map below.
Common Hosts: deer, cattle and man