Key to the Species of Aceria (Keifer, 1944) in Taiwan

1 Empodium with 5 or more rays...................................................................................................................6

- Empodium 4 rayed......................................................................................................................................2

2 Prodorsal shield design with a median line................................................................................................4

- Prodorsal shield design with median line absent........................................................................................3

3 Admedian lines connected at base, U-shaped ........................................................ A. serratifoliae sp. nov.

- Admedian lines not connected at base ................................................................... A. taiwanensus sp. nov.

4 Prodorsal shield design with granules at ridges .................................................... A. litseae (Keifer, 1972)

- Prodorsal shield design without granules at ridges.....................................................................................5

5 1st submedian lines connected at base, U-shape ..................................................... A. gallae Huang, 1996

- 1st submedian lines divergent at base................................................................. A. spicati (Stebbins, 1909)

6 Empodium 5 rayed......................................................................................................................................7

- Empodium 6-7 rayed................................................................................................................................16

7 Prodorsal shield design with granules........................................................................................................8

- Prodorsal shield design with ridges............................................................................................................9

8 Prodorsal shield lobe acute at apex ................................................................. A. eriobotrya (Keifer, 1938)

- Prodorsal shield lobe divided at apex ............................................................. A. shepherdiae Keifer, 1966

9 Prodorsal shield design with median line absent......................................................................................10

- Prodorsal shield design with median present............................................................................................11

10 Admedian lines complete ......................................................................................... A. sylvestrae sp. nov.

- Admedian lines from base to basal 1/3 .......................................................... A. yushania K. Huang, 2001

11 Median line discontinuous ................................................................................... A. monoica Huang, 2001

- Median line continuous.............................................................................................................................12

12 Median line incomplete .......................................................................................... A. pipturi Keifer, 1966

- Median line complete...............................................................................................................................13

13 Median line with arrow-like figure at base ............................................................ A. litchii (Keifer, 1943)

- Median line without arrow-like figure at base..........................................................................................14

14 Admedian lines subparallel ............................................................................. A. jasminoidis Huang, 2001

- Admedian lines not subparallel.................................................................................................................15

15 Admedian line sinuous ..................................................................................... A. lanyuensis Huang, 2001

- Admedian line divergent at base ........................................................................... A. kuko (Kishida, 1927)

16 Empodium 7 rayed ......................................................................................................... A. virosae sp. nov.

- Empodium 6 rayed....................................................................................................................................17

17 Admedian lines with transverse lines.......................................................................................................18

- Admedian lines without transverse lines ............................................................... A. sacchari Wang, 1964

18 Median and admedian lines with transverse lines at basal 1/4 and at half-way point ................................... ................................................................................................................................ A. pobuzii Huang, 1996

- Median and admedian lines with transverse lines at basal 1/5 and 1/3....................................................19

19 1st submedian line with forked line at basal 2/3 .............................................. A. mikaniae (Nalepa, 1918)

- 1st submedian line without forked line ............................................................... A. roxburghianae sp. nov.