Scirtothrips, Shull, 1909

Rodríguez-Arrieta, Jesús Alexander, Cambero-Campos, Octavio Jhonathan & González-Hernández, Héctor, 2024, Taxonomic changes in Scirtothrips species (Thysanoptera: Thripidae) from México, Zootaxa 5489 (1), pp. 173-183 : 180-181

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

Figures

FIGURES 1–3. (1)Mouth-cone short,Holotype of S.albosilvicola; (2) mouth-cone long, crossing through forecoxae and thebase of prosternum, female Paratype of S. musciaffinis; (3) discal microtrichia on tergite IX, female Paratype of S. cognatoalbus.

FIGURES 4–7. (4) S. dorsalis: sternites V–VI covered with discal microtrichia (arrows); (5) S. citri: sternites V–VII with fine microtrichia only on lateral sides (arrows); (6) S. dorsalis: antecostal dark lines on abdominal tergites, median region and lateral thirds are shaded; (7) S. citri: abdomen uniformly pale.

FIGURES 8–11. (8) S. abditus: ocellar setae III (oIII) arising between fore and hind ocellus, poI–II: post-ocular setae I and II; (9) S. perseae: oIII arising inner at the margin of the ocellar triangle; (10) S. aztecus: drepanae on male tergite IX (arrow); (11) S. abditus: length of post-ocular setae I and II (poI–II).

FIGURES 12–17. (12) Metanotal anterior margin (Mam) and median metasternal (mtt) setae, Holotype of S. aztecus; (13) S. perseae: position of the median metasternal (mtt) setae from the metanotal anterior margin (Mam). Posteromarginal setae on pronotum (S1–S3), (14) female Paratype of S. bisbravoae; (15) S. citri; (16) Holotype of S. musciaffinis; (17) Holotype of S. cognatoalbus.