Leptothrips, Hood, 1909

Mound, Laurence & O’Donnell, Cheryle, 2017, Predation, phytophagy and character state confusion among North American species of the genus Leptothrips (Thysanoptera: Phlaeothripinae), Zootaxa 4294 (3), pp. 301-315 : 306

Key to the Leptothrips species from North America

1. Fore tarsus of female with small or minute tooth on inner margin................................................ 2

- Fore tarsus of female without a tooth on inner margin......................................................... 4

2. Fore wing with 6–10 duplicated cilia; antennal segment III with one sense cone; pronotal mid-lateral setae present... distalis

- Fore wing without duplicated cilia; combination of other characters different......................................3

3. Pronotum without any lines of sculpture medially; antennal segment III with one sense cone; antennal segments IV–VI uni- formly brown; pronotal mid-lateral setae present ( Fig. 22 )............................................ fasciculatus

- Pronotum medially with closely spaced transverse sculpture lines; antennal segment III with no sense cone; antennal segments IV–VI largely yellow; pronotal mid-lateral setae absent ( Fig. 24 )........................................ purpuratus

4. Pronotum medially with prominent sculpture lines...........................................................5

- Pronotum with a few striae laterally and near posterior margin, but sculpture lines medially either absent or very weak.... 1 1

5. Antennal segment II asymmetric with apical margin oblique ( Fig. 6 )........................................ opimus

- Antennal segment II symmetric, apex transverse.............................................................6

6. Antennal segment III with no sense cone, length of segment III usually no more than sub-equal to length of segment II; length of antennal segments III+IV no more than 125 microns [fore wing with number of duplicated cilia varying from 0–6]; appar- ently host specific to Larrea tridentata ................................................................ larreae

- Antennal segment III with one sense cone; length of antennal segments III+IV usually more than 140 microns............ 7

7. Antennal segment IV with four major sense cones............................................................8

- Antennal segment IV with three major sense cones..........................................................10

8. Maxillary stylets retracted into head to level of postocular setae, and close together medially ( Fig. 5 ).......... occidentalis

- Maxillary stylets retracted about half way to postocular setae and wide apart ( Figs 1–3 )..............................9

9. Fore wing with 5 or more duplicated cilia; pronotal striae weak and widely spaced medially....................... mali

- Fore wing usually without, or with very few duplicated cilia; pronotal striae strongly developed............... heliomanes

10. Fore wing with duplicated cilia present............................................................. mcconelli

- Fore wing not known to have any duplicated cilia....................................................... papago

11. Antennal segment IV with 2 sense cones................................................................. 12

- Antennal segment IV with 3 or 4 sense cones............................................................. 13

12. Pronotum as dark as head, hind tibiae uniformly dark brown................................................. pini

- Pronotum paler than head, hind tibiae yellow distally................................................. singularis

13. Antennal segment IV with three major sense cones................................................ macroocellatus

- Antennal segment IV with four major sense cones...........................................................14

14. Antennal segment IV without a small ancillary sense cone............................................... oribates

- Antennal segment IV with a small ancillary sense cone on outer margin..................................... cassiae

Figures

FIGURES 17 – 24. Leptothrips species of North America – pronotum. (17) maliaffinis holotype; (18) mali; (19) papago; (20) heliomanes; (21) macroocellatus; (22) fasciculatus; (23) pini; (24) purpuratus.

FIGURES 1 – 6. Leptothrips species of North America. (1) cassiae; (2) mali; (3) pini; (4) purpuratus; (5) occipitalis holotype; (6) opimus holotype, antennal segments I – III.