Scirtothrips

Mound, L. A., 2015, Genera of the Scirtothrips genus-group (Thysanoptera, Thripidae) with a new species of Siamothrips from Malaysia, Zootaxa 4021 (2), pp. 387-394 : 388

Key to genera of Scirtothrips genus-group

1. Antennae 6-segmented...................................................................... Drepanothrips

-. Antennae 7 or 8-segmented.............................................................................. 2

2. Antennae 7-segmented................................................................................. 3

-. Antennae 8-segmented................................................................................. 5

3. Antennae widely separated, interantennal projection wider than length of antennal segment I; first ocellar setae long, about 3 times as long as distance between posterior ocelli; pronotum with a pair of long anteromarginal setae........ Kenyattathrips

-. Antennae not widely separated, interantennal projection not wider than length of antennal segment I; first ocellar setae not elongate; pronotum with no long anteromarginal setae........................................................ 4

4. Mesonotal median and submedian setae arising almost in a transverse line; abdominal tergites with many rows of closely spaced microtrichia on lateral thirds; tergal median setae S1 longer than distance between their bases....... Anascirtothrip s

-. Mesonotal submedian setae arising near posterior margin, posterolateral to median setae; abdominal tergites lateral thirds with few microtrichia on sculpture lines; tergal median setae S1 shorter than the distance between their bases..... Parascirtothrips

5. Abdominal tergites IV–VII without rows of microtrichia on lines of sculpture laterally ( Fig. 4 ); fore wing second vein with complete row of about 16 setae................................................................ Scirtidothrips

-. Tergal lateral thirds with closely spaced rows of microtrichia on sculpture lines; fore wing second vein with less than 12 setae................................................................................................... 6

6. Tergal setae S1 and S2 arise laterally closer together than their length; head with ocellar setae pair I absent, no setal pair in front of first ocellus............................................................................ Biltothrips

-. Tergal setae S1 usually close together medially, distant from setae S2; ocellar setae pair I present, sometimes wide apart (absent in some specimens of Scirtothrips malayensis )....................................................... 7

7. Abdominal sternites IV–VI with median two pairs of posteromarginal setae arising in front of posterior margin ( Fig. 2 )................................................................................................ Cercyothrips

-. Abdominal sternites IV–VI with posteromarginal setae arising at margin......................................... 8

8. Tergite IX with pair of campaniform sensilla present medially........................................... Ajothrips

-. Tergite IX without any campaniform sensilla............................................................... 9

9. Fore wing second vein without setae; pronotum trapezoidal, as long as wide ( Fig. 10 ); sternites with complete posteromarginal comb of microtrichia; [where known, male apterous]................................................ Siamothrips

-. Fore wing second vein with some setae; pronotum transverse, wider than long; sternites rarely with complete posteromarginal comb of microtrichia; [where known, male macropterous]................................................... 10

10. Major setae on pronotum and fore wing tapering and sharply pointed.................................... Scirtothrips

-. Major setae on pronotum and fore wing thickened, parallel-sided and bluntly pointed ( Fig. 5 ).............. Ephedrothrips

Figures

FIGURES 1 – 7. Cercyothrips: (1) pronotum, mesonotum and metanotum; (2) sternites IV – VI. Scirtidothrips: (3) pronotum, mesonotum and metanotum; (4) tergites III – V. Ephedrothrips ontigolae (paratype): (5) pronotum; (6) tergites III – V. Scirtothrips palloris (Hood) comb. n: (7) pronotum.

FIGURES 8 – 17. Siamothrips initium sp. n: (8) Head, (9) frons; (10) Pronotum; (11) Mesonotum and metanotum; (12) Antenna; (13) Abdominal tergites VI – X; (14) Mesosternum and metasternum; (15) Fore wing; (16) Abdominal tergites VII – IX (close up); (17) Abdominal sternites VI – VII.