EXTENSION OF THE RANGE OF DERMACENTOR-VARIABILIS (ACARI, IXODIDAE) INPENNSYLVANIA

The American dog tick, Dermacentor variabilis (Say), until recently wa s recorded only from the southeastern and southwestern counties of Pen nsylvania. Since 1968, this species has expanded its range and is repo rted from 63 of Pennsylvania's 67 counties. This range extension is a matter of concern to the medical community and to physicians throughou t Pennsylvania, particularly those with practices in areas where this tick was previously unknown and who may not be familiar with the sympt oms of Rocky Mountain spotted fever.