Key to females of species Aceria known from caryophyllaceous hosts

1 Prodorsal shield without lines........................................................ Aceria silenes (Liro, 1940)

- Prodorsal shield with lines.............................................................................. 2

2 Empodium 7-rayed.................................................................................... 3

- Empodium less than 7-rayed.............................................................................4

3 Seta sc 20 shorter than prodorsal shield 34.......................................... Aceria georghioui Keifer, 1959

- Seta sc 45–70 longer than prodorsal shield 32–42................................... Aceria feketeistvani Ripka, 2016

4 Empodium 6-rayed....................................................................................5

- Empodium 5-rayed....................................................................................7

5 Ornamentation of prodorsal shield a network of lines............................... .. Aceria paradianthi Keifer, 1952

- Ornamentation of prodorsal shield not a network of lines......................................................6

6 Seta sc slightly longer than prodorsal shield, opisthosoma with 90 annuli............ .. Aceria moehringiae (Lindroth, 1899)

- Seta sc distinctly shorter than prodorsal shield, opisthosoma with 63–68 annuli.................................................................................... Aceria ankarensis Denizhan, Monfreda, Cobanoglu & de Lillo, 2006

7 Prosternal apodeme distinct, sternal line present.............................................................8

- Coxae I narrowly separated, sternal line absent, and prodorsal shield without frontal lobe....... Aceria belarexi Ripka, 2016

8 Prodorsal shield semicircular........................................................................... ..9

- Prodorsal shield subtriangular........................................................................... 11

9 Seta 3a longer than 15 µm.............................................................................. 10

- Seta 3a short, 9 µm long........................................................ Aceria dianthi (Lindroth, 1904)

10 Prodorsal shield without frontal lobe, seta c2 35 long, female genital coverflap with 10 ridges.................................................................................................. Aceria gypsophilae Roivainen, 1950

- Prodorsal shield with a short frontal lobe, seta c2 52–55 long, female genital coverflap with 13–14 ridges.................................................................................................. Aceria wassalberti n. sp.

11 Prodorsal shield with short frontal lobe.............................................. Aceria colocense Ripka, 2013

- Prodorsal shield without frontal lobe............................................... Aceria cerastii (Nalepa, 1892)