Table 1 Summary of most important diagnostic characters that differ or are similar between Ixodes rugicollis and I. cornutus females

Palps dorsally

1.Medially strongly curved in its posterior half, segment II. posteriorly tapering at nearly perpendicular angle to “stalk” (Fig. 1A)

2.All palpal setae short (< 30 μm)

1.Medially equally curved in its anterior and posterior halves, segment II. posteriorly tapering at acute angle to “stalk” (Additional File 2A)

2.All palpal setae short (< 30 μm) (Additional File 1)

Width of “stalk” of palpal segment II

3.Approx. one third of palpal width (Fig. 1A)

3.Approx. half of palpal width (Additional File 2A)

Areae porosae

4.Small, circular, with approx. 130 μm distance between them (Fig. 1A)

4.Irregularly oval, with approx. 50 μm distance between them (Additional File 2A)

Scutum shape

5.Slightly broader than long, broadest at approx. mid-length,

6.Posterolateral margin concave (Fig. 1.B, Additional File 3A)

5.Slightly longer than broad, broadest anteriorly at approx. one third of length,

6.Posterolateral margin straight (Additional File 2.A)

Hypostome dentition

7.2/2, apically (anterior quarter) 3/3 or higher (Fig. 1C)

7.2/2, apically (anterior quarter) 3/3 or higher (Additional File 1)

Coxa I

8.Short internal spur present (Fig. 1D)

8.Short internal spur inapparent (Additional File 2B)

Anal valves

9.Anterior three setae vertically, posterior two setae horizontally (Additional File 3C)

9.Anterior three setae vertically, posterior two setae horizontally (Additional File 1)