Key to the Scirtothrips species in México

1. Mouth-cone short, reaching fore-coxae but does not cross until prosternum base (Fig. 1); with/without discal microtrichia on tergite IX........................................................................................... 2

- Mouth-cone long, reaching the base of prosternum (Fig. 2); tergite IX always with discal microtrichia (Fig. 3).......... 10

2. Abdominal sternites III–VI full covered with microtrichia (Fig. 4); males without drepanae on tergites IX............... 3

- Abdominal sternites III–VI with microtrichia restricted to lateral thirds (Fig. 5).................................... 4

3. Antecostal line on tergites III–VIII dark; central and lateral sides of tergites generally with brown markings (Fig. 6). dorsalis

- Not this combination of morphological characters............................................... zacualtipanensis

4. Anterior margin of abdominal tergites dark; sometimes shaded medially and laterally............................... 5

- Abdominal tergites with anterior margin pale and without shading areas (Fig. 7)................................... 9

5. Head with ocellar setae III arising further apart, between fore and hind ocellus and sometimes outer at the margin of the ocellar triangle (Fig. 8)...................................................................................... 6

- Head with ocellar setae III arising close to each other and always inside the ocellar triangle (Fig. 9); males with drepanae on tergite IX (Fig. 10).................................................................................... 8

6. Anterior region of head pale; abdominal tergite VIII covered with discal microtrichia; post-ocular setae I longer than pair II (Fig. 11)............................................................................................ 7

- Anterior region of the head shaded; tergite VIII without discal microtrichia and tergite IX covered only at the posterior half; post-ocular setae I and II subequal in length........................................................ longipennis

7. Abdominal tergite IX without discal microtrichia....................................................... abditus

- Abdominal tergite IX fully covered with discal microtrichia.......................................... albosilvicola

8. Median pair of metanotal setae arising at the anterior margin (Fig. 12); sternites III–VI with antecostal line light brown to brown......................................................................................... aztecus

- Median pair of metanotal setae arising in front of the anterior margin (Fig. 13); sternites III–VI with antecostal line dark.................................................................................................. perseae

9. Pronotum posteromarginal setae length S2 and S3 subequal, S1 usually 0.25–0.30 times the half of S2 length (Fig. 14), sometimes reaching the half of S2; metanotum median setae arising at the anterior margin................... bisbravoae

- Pronotum posteromarginal setae S1 and S3 subequal in length (Fig. 15), sometimes across to the half of S2; metanotum median setae in front of anterior margin....................................................................... citri

10. Metanotal median setae arising at the anterior margin (Fig. 12); males with drepanae on tergite IX (Fig. 10)............ 11

- Metanotal median setae in front of anterior margin (Fig. 13); male tergite IX without drepanae.................... albus

11. Pronotum posteromarginal setae S1, S2 and S3 subequal in length (Fig. 16).............................. musciaffinis

- Pronotum posteromarginal setae S2 and S3 subequal, S1 reaching half of S2 (Fig. 17).................... cognatoalbus