Deer keds are obligatory haematophagous parasites of large homeothermic animals, particularly cervids. Two of the five known species occurring in Europe— Lipoptena cervi (Linnaeus) and L. fortisetosa Maa—are known to have a relatively wide distribution. Lipoptena fortisetosa is considered to have been introduced into Europe with sika deer from the Eastern Palaearctic and is continuously expanding its range. Little is known about the medical importance of deer keds, but they can cause hair loss in cervids and are suspected to be vectors of several diseases.
Details of the distribution of Lipoptena fortisetosa in Europe, including its northernmost record, are provided. This species has been shown to have a viable population in Southern Estonia. Furthermore, the differences from allied L. cervi are discussed, based on morphological and molecular characters.