Key to the females of Euseius described or reported from India (modified from Kar & Karmakar, 2021b)
1. Ventrianal shield pentagonal, dentitions of cheliceral fixed digit clustered apically distal to pilus dentilis with one basal tooth.................................................................. Euseius mangiferae (Ghai & Menon, 1967)
- Ventrianal shield not pentagonal, dentitions of cheliceral fixed digit clustered apically distal to pilus dentilis without any basal tooth............................................................................................... 2
2. Setae s4, S4 and S5 barbed.................................................. E. sativum Karmakar & Gupta, 2014
- Setae s4, S4 and S5 not barbed........................................................................... 3
3. Seta J2 longer than setae j1, j3, Z4 ............................................. E. eucalypti (Ghai & Menon, 1967)
- Seta J2 always shorter than any of the setae j1, j3, Z4 ......................................................... 4
4. Seta JV1 on anterior margin of ventrianal shield............................................................. 5
- Seta JV1 migrated posteriorly away from anterior margin of ventrianal shield...................................... 9
5. Dorsum smooth, calyx of spermatheca bell-shaped................................ E. chikmagalurensis (Gupta, 1986)
- Dorsum reticulated, calyx of spermatheca not bell-shaped..................................................... 6
6. Dorsum striated forming longitudinal cells, cheliceral movable digit bidentate.......... E. hima (Pritchard & Baker, 1962)
- Dorsum reticulated forming net-like transverse cells, cheliceral movable digit unidentate............................ 7
7. Peritreme extending beyond bases of seta j3 ......................................... E. chitradurgae (Gupta, 1986)
- Peritreme not extending beyond bases of z2 ................................................................ 8
8. Leg IV with three macrosetae.................................................... E. karpasae Kumar et al., 2022
- Leg IV with only one macroseta on basitarsus...................................... E. kalimpongensis (Gupta, 1969)
9. All dorsal setae much shorter than j1 and Z5 ............................................................... 10
- All dorsal setae of various lengths with respect to j1 and Z5 ................................................... 13
10. All macrosetae of leg IV spatulated............................................. E. macrospatulatus (Gupta, 1986)
- All the macrosetae of leg IV not spatulated................................................................ 11
11. Dorsum smooth, posterior margin of sternal shield concave......................... E. sacchari (Ghai & Menon, 1967)
- Dorsum anterolaterally striated, posterior margin of sternal shield never concave.................................. 12
12. Posterior margin of sternal shield inconspicuous................................. E. vikrami Karmakar & Gupta, 2014
- Sternal shield conspicuous with posterior projections....................................... E. ovalis (Evans, 1953)
13. Major duct of spermatheca banded with light sclerotisation................................... E. aridophilus sp. nov.
- Major duct of spermatheca never banded with sclerotisation.................................................. 14
14. Calyx of spermatheca tubular........................................................................... 15
- Calyx of spermatheca not tubular........................................................................ 29
15. Calyx of spermatheca banded.................................... E. bandispermathecae Pramanik & Karmakar, 2016
- Calyx of spermatheca not banded........................................................................ 16
16. Atrium of spermatheca falcate................................................. E. curcasae Santhosh et al., 2018
- Atrium of spermatheca never falcate..................................................................... 17
17. Sternal shield reticulated, calyx of spermatheca sclerotised proximally................ E. tripurii Kar & Karmakar, 2022a
- Sternal shield smooth, calyx of spermatheca not sclerotised proximally.......................................... 18
18. Seta j3 twice the length of j1, dentitions of fixed digit of chelicerae distributed evenly along its length.................................................................................................... E. hibisci (Chant, 1959)
- Seta j3 shorter or subequal to j1, dentitions of fixed digit of chelicerae clustered apically............................ 19
19. Peritreme not extending beyond the bases of seta z2 ......................................................... 20
- Peritreme extending beyond bases of seta z2 ............................................................... 23
20. Dorsal seta s4 minute 6–9................................................... E. pariyarensis Santhosh et al., 2018
- Dorsal seta s4 longer than 20........................................................................... 21
21. Leg IV macrosetae knobbed, dorsum smooth, seta z4 crossing bases of s4 ............... E. scutalis (Athias-Henriot, 1958)
- Leg IV macrosetae pointed, dorsum never smooth, seta z4 not touching bases of s4 ................................ 22
22. Dorsal shield antero-laterally striated, macroseta on genu shorter 30–33.......................... E. tamilicus sp. nov.
- Dorsal shield antero-laterally striated, macroseta on genu longer 52–57........... E. delhiensis (Narayanan & Kaur, 1959)
23. Sternal shield 1.5 times longer than wide......................................... E. papayensis (Sadanandan, 2006)
- Sternal shield as long as wide........................................................................... 24
24. Atrium of spermatheca horse-shoe shaped.................................... E. tubuliferus Kar & Karmakar, 2022b
- Atrium of spermatheca not horse-shoe shaped.............................................................. 25
25. Seta j1 more than twice the length of Z5 ......................................... E. rhododendronis (Gupta, 1970)
- Seta j1 not more than 1.5 times the length of Z5 ............................................................ 26
26. Dorsal shield reticulated with longitudinal cells............................................................ 27
- Dorsal shield anterolaterally striated..................................................................... 28
27. Cheliceral movable digit toothless, seta S5 longer 28–34.................................. E. alstoniae (Gupta, 1975)
- Cheliceral movable digit unidentate, seta S5 shorter 14–17.......................... E. neoalstoniae Kumar et al., 2022
28. Longer dorsal seta s4 43, leg IV macrosetae knobbed.................................... E. concordis (Chant, 1959)
- Shorter dorsal seta s4 18 –23, leg IV macrosetae blunt......................... E. bomdilae Pramanik & Karmakar, 2016
29. Calyx of spermatheca medially constricted................................................................ 30
- Calyx of spermatheca not constricted medially............................................................. 40
30. Calyx of spermatheca annulated.............................................. E. insanus (Khan & Chaudhri, 1969)
- Calyx of spermatheca not annulated...................................................................... 31
31. Seta Z5 twice the length of j1, calyx of spermatheca constricted throughout its length................................................................................................... E. astrictus Karmakar & Bhowmik, 2018
- Seta Z5 less than twice that of j1, calyx of spermatheca not constricted throughout the length........................ 32
32. Sternal shield smooth................................................................................. 33
- Sternal shield reticulated............................................ E. madhubanensis Karmakar & Biswas, 2023
33. Calyx of spermatheca oyster (freshwater shell) shaped.......................... E. jhinukae Karmakar & Biswas, 2023
- Calyx of spermatheca not oyster shaped.................................................................. 34
34. Seta j1 twice that of j3, cheliceral movable digit bidentate...................... E. tripuraensis Kar & Karmakar, 2022a
- Seta j1 not twice than j3, cheliceral movable digit not bidentate................................................ 35
35. Dorsum smooth, ventrianal shield pentagonal................................... E. bambusae (Ghai & Menon, 1967)
- Dorsum reticulated, ventrianal shield not pentagonal........................................................ 36
36. Both setae r3 and R1 located off dorsal shield.............................................................. 37
- At least one of setae r3 and R1 located on dorsal shield...................................................... 38
37. Leg IV macrosetae sharp, cheliceral movable digit unidentate...................... E. prasadi Chant & McMurtry, 2005
- Leg IV macrosetae blunt, cheliceral movable digit toothless............................... E. coccineae (Gupta, 1975)
38. Any one of setae r3 and R1 located on-shield.............................................................. 39
- Both the setae r3 and R1 located on-shield............................................ E. ahaioensis (Gupta, 1992)
39. Only seta r3 located on dorsal shield............................................. E. finlandicus (Oudemans, 1915)
- Only seta R1 located on dorsal shield....................................... E. spontaneum Kar & Karmakar, 2022a
40. Calyx of spermatheca flared at atrium.................................................................... 41
- Calyx of spermatheca never flared at atrium............................................................... 45
41. Seta j1 twice the length of j3........................................................................... 42
- Setae j1 and j3 subequal............................................................................... 43
42. Seta R1 on dorsal shield, leg IV macrosetae capitate............................ E. dwakiensis Kar & Karmakar, 2021b
- Seta R1 off dorsal shield, leg IV macrosetae not capitate............................. E. neococcineae (Gupta, 1978c)
43. Calyx of spermatheca annulated................................................ E. fascae Kar & Karmakar, 2021b
- Calyx of spermatheca not annulated...................................................................... 44
44. Leg IV macrosetae capitate............................................... E. coccosocius (Ghai & Menon, 1967)
- Leg IV macrosetae hyaline-tipped........................................ E. sajnekhalicus Kar & Karmakar, 2021a
45. Calyx of spermatheca fundibular.................................... E. arunachalensis Pramanik & Karmakar, 2016
- Calyx of spermatheca not fundibular..................................................................... 46
46. Sternal shield smooth................................................................................. 47
- Sternal shield rugose.................................................................................. 49
47. Movable digit of chelicerae toothless.......................................... E. chittooriensis Kumar et al., 2022
- Movable digit of chelicerae unidentate................................................................... 48
48. Setae j1 36, r3 26, R1 20, SgeIV 23............................................... E. vignus Rishi & Rather, 1983
- Setae j1 28–30, r3 12–14, R1 11–14, SgeIV 37........................ E. sundarbanensis Karmakar & Bhowmik, 2018
49. Sternal shield reticulated, peritreme extended beyond seta j3, leg IV macrosetae pointed.................................................................................................... E. coimbatorensis Suresh et al., 2014
- Sternal shield striated, peritreme not extended beyond seta j3, leg IV macrosetae blunt............... E. madrasi sp. nov.