Stenchaetothrips Bagnall

Masumoto, Masami & Okajima, Shûji, 2013, Review of the genus <i> Thrips </ i> and related genera (Thysanoptera, Thripidae) from Japan, Zootaxa 3678 (1), pp. 1-65 : 7-8

Stenchaetothrips Bagnall

Wings fully developed. Ocellar setae I absent, setae II distinctly longer than setae III ( Figs. 1, 8–10 ). Antennae ( Fig. 2 ) 7- segmented, segment I without median dorsal apical setae, II with a MD seta below CPS, III and IV with sensoria forked, III–VI with some rows of microtrichia on both dorsal and ventral surfaces. Pronotum ( Fig. 1 ) with 2 pairs of developed posteroangular setae. Mesonotum ( Fig. 40 ) with median pair of setae situated far from posterior margin. Metascutum sculptured with narrow spaced longitudinal anastomosing striae except anteromedially; median pair of setae behind anterior margin. Prosternal ferna weakly connected at middle; basantra membranous, without setae. Spinula usually absent from both meso- and metasternal endofurca, sometime present on mesosternum. Fore wing ( Fig. 41 ) first vein usually with long gap in setal row, second vein with many setae equally spaced; clavus usually with five veinal and one discal seta; posteromarginal fringe cilia wavy. Abdominal tergites and sternites without posteromarginal craspeda, but often with small teeth or scallops along posterior margin; tergite II with 4 lateral marginal setae; tergites VI–VIII ( Figs. 25, 26 ) with paired ctenidia; tergite VIII usually with posteromarginal comb complete; tergite X with longitudinal median split almost complete; sternites III to VII with 3 pairs of posteromarginal setae, II with 2 pairs, all posteromarginal setae arising from posterior margin on II to VII except S1 setae on VII situated ahead of posterior margin; pleurotergites without discal setae. Ovipositor developed. In male, abdominal sternites III to VII ( Fig. 7 ) each with a pore plate; posteromarginal teeth on tergites and sternites usually developed more than in female ( Figs. 16 , 53 ).

Species of this genus are specific to plants in the family Poaceae and can be distinguished from Thrips only by having ocellar setae II much longer than setae III.

Key to Stenchaetothrips species from Japan (adult female)

( mucunae is excluded)

1 Fore wing uniformly dark in distal four-thirds............................................................... 2

- Fore wing not uniformly dark in distal four-thirds ( Fig. 41 ).................................................... 6

2 Fore wing uniformly dark; abdominal tergite IX ( Fig. 15 ) with posterior pair of CPS only; postocular setae I often absent ( Fig. 10 ).......................................................................................... biformis

- Fore wing not uniformly dark, basal fourth pale; abdominal tergite IX ( Fig. 31 ) with both anterior and posterior pairs of CPS; postocular setae I always present ( Fig. 27 )................................................................. 3

3 Postocular setae III distinctly longer than setae I ( Fig. 27 )..................................................... 4

- Postocular setae III subequal to, at least not distinctly longer than, setae I ( Figs. 1 , 47, 48 )........................... 5

4 Abdominal tergites ( Fig. 30 ) with a few small microtrichia laterally, but without scallops and microtrichia medially on posterior margin; all femora almost yellowish; metascutum ( Fig. 29 ) always with paired CPS....................... minutus

- Abdominal tergites ( Figs. 20, 21 ) with distinct microtrichia laterally, and with scallops or irregular microtrichia medially on posterior margin; all femora dark; metascutum usually without paired CPS, sometimes with paired or only one CPS................................................................................................ dentatus sp. n.

5 Body uniformly dark; mesothoracic endofurca with spinula distinct; mesonotum with paired CPS anteromedially; abdominal tergites ( Fig. 4 ) with teeth directed to outside along posterior margin; pronotum distinctly sculptured ( Fig. 1 ).................................................................................................... amamiensis sp. n.

- Body bicoloured, pterothorax yellowish; mesothoracic endofurca without spinula or with spinula very weak; mesonotum usually without paired CPS anteromedially; abdominal tergites often with teeth directed to outside along posterior margin ( Fig. 52 ); pronotum weakly sculptured ( Figs. 47, 48 )........................................................ undatus

6 Body uniformly yellow; fore wings uniformly pale; postocular setae III subequal to setae I ( Fig. 23 ); mesonotum without CPS anteromedially; abdominal tergite VIII ( Fig. 26 ) with posteromarginal comb of irregular small teeth......... langkawiensis

- Body not uniformly yellow, often yellow with posterior segments of abdomen dark; fore wings ( Fig. 41 ) variable, usually pale with shaded median third to fourth but often uniformly pale; postocular setae III distinctly longer than setae I ( Fig. 38 ); mesonotum ( Fig. 40 ) with paired CPS anteromedially; abdominal tergite VIII ( Fig. 43 ) with posteromarginal comb long and fine.................................................................................... pleioblasti sp. n.

Figures

FIGURES 1–17. Stenchaetothrips species. S. amamiensis sp. n., female 1–4: (1) Head & pronotum; (2) Antenna, right; (3) Metascutum; (4) Tergite VII. S. amamiensis sp. n., male 5–7: (5) Tergites VII–VIII, sculpture omitted; (6) Tergite IX, sculpture omitted; (7) Sternite VII, sculpture omitted. S. biformis, female 8–15: (8) Head & pronotum; (9) Postocular setae, setae I present; (10) Postocular setae, setae I absent; (11) Antenna, right; (12) Metascutum; (13) Tergite VII; (14) Posterior margin of tergite VII with large teeth; (15) Tergites VIII to X. S. biformis, male 16–17: (16) Tergite VII, sculpture omitted; (17) Sternite VII, sculpture omitted.

FIGURES 38–50. Stenchaetothrips species. S. pleioblasti sp. n., female 38–43: (38) Head & pronotum; (39) Antenna, right; (40) Mesonotum & metascutum; (41) Fore wing, right; (42) Tergite V & pleurotergite, right side; (43) Tergites VIII–X. S. pleioblastus sp. n., male 44–46: (44) Tergites VII–VIII, sculpture omitted at left side; (45) Posterior margin of tergite VIII with fine microtrichia; (46) Sternites VII–VIII, sculpture omitted. S. undatus. 47–50: (47) Head, female, from Fukushima Pref., Honshu; (48) Head, female, from Ishigaki-jima, Islands; (49) Antenna, female, from Ishigaki-jima Island; (50) Antenna, female, from Fukushima Pref., Honshu.

FIGURES 18–26. Stenchaetothrips species. S. dentatus sp. n., female 18–22: (18) Head & pronotum; (19) Antenna, right; (20) Tergite II, left side; (21) Tergite V, left side; (22) Tergite VIII, sculpture omitted at left side. S. langkawiensis, female 23– 26: (23) Head & pronotum; (24) Antenna, right; (25) Tergite VI, left side; (26) Tergites VIII–X.

FIGURES 51–61. Stenchaetothrips undatus 51–53: (51) Mesonotum & metascutum; (52) Tergite VII, left side; (53) Tergites VII–X, male, sculpture omitted at right side of tergites VII–VIII and tergite IX. Thrips alliorum, female 54–61: (54) Head & pronotum; (55) Antenna, right; (56) Metascutum; (57) Tergite VI & pleurotergite, left side; (58)Tergites VIII–X; (59) Sternite VII, sculpture omitted. T. alliorum, male 60–61; (60) Tergites IX–X; (61) Sternite VI.

FIGURES 27–37. Stenchaetothrips species. S. minutus, female 27–31: (27) Head & pronotum; (28) Antenna, right; (29) Metascutum; (30) Tergite VI, left side; (31) Tergites VIII–X. S. mucunae, holotype female 32–35: (32) Head & pronotum, sculpture omitted; (33) Antennal segments II–VII, left, microtrichia, setae and sensoria omitted; (34) Metascutum; (35) Tergite V, left side, sculpture omitted. S. mucunae, “allotype” male 36–37: (36) Tergite VI, left side, sculpture omitted; (37) Sternite VII, sculpture omitted.