Ethirothrips longisetis (Ananthakrishnan & Jagadish)

Okajima, Shûji & Masumoto, Masami, 2023, Six genera of the subtribe Macrothripina from Southeast Asia to Taiwan (Thysanoptera, Phlaeothripidae, Idolothripinae), Zootaxa 5291 (1), pp. 1-74 : 33-34

Ethirothrips longisetis (Ananthakrishnan & Jagadish)

( Figs 77–83 , 224 )

Diceratothrips (Diceratothrips) longisetis Ananthakrishnan & Jagadish, 1970: 268–269 .

E. longisetis was originally described from Darjeeling, India, based on the holotype female and allotype male. Subsequently, Zhang (1984) recorded this species from Hainan, China, and the record includes only the locality and habitat with a line drawing of the head and prothorax, but there is no morphological or taxonomic consideration. Here , one female and one male collected from Laos listed below are identified as this species, but these specimens have somewhat larger bodies and shorter posteromarginal setae (S1 and S2) on abdominal tergite IX than the type series, and a full description of them is given.

Female (macroptera). Distended body length: 5.2mm. Colour uniformly dark brown. Antennal segment III rather paler than segment IV, with basal 1/4 yellowish. Tarsi brown. Fore wings shaded with brown, with a pale brown streak in basal half. Prominent setae yellow to brownish yellow, cheek setae brownish. Head ( Fig. 78 ) elongate, 1.57 times as long as broad, broadest across cheeks just behind eyes; dorsal surface almost smooth. Cheeks sub-parallel, almost straight, but weakly constricted at anterior 1/3 and base, very weakly convex medially; each with some stout setae. Postocular setae rather close together, situated behind inner margins of eyes, much longer than eyes, nearly pointed; postocellar setae a little longer than diameter of a posterior ocellus, situated behind posterior ocelli. Eyes comparatively small, 0.23 times as long as head; posterior ocelli slightly apart from eyes, 25–30μm in diameter, 83μm apart from each other. Antennae 1.76 times as long as head; segment VIII constricted at base; segment III ( Fig. 80 ) elongate, 3.5 times as long as broad, longer than segment IV; sense-cones short, segment IV with four sense-cones. Maxillary stylets deeply retracted, reaching postocular setae, about 1/3 of head width apart from each other. Pronotum ( Fig. 78 ) about half the length of head, twice as broad as long; dorsal surface almost smooth. Prominent setae nearly pointed, epim the longest, longer than median length of pronotum. Mesopresternum ( Fig. 82 ) narrowly boat-shaped. Metanotum ( Fig. 79 ) without CPS. Fore femora moderately enlarged, with many long (60–90μm) and slender setae ( Fig. 77 ) in addition to a dorso-external seta (about 150μm); fore tarsus ( Fig. 83 ) with a wide-based stout tooth. Fore wings each with 32–34 duplicated cilia; sub-basal setae sharply pointed. Pelta ( Fig. 79 ) trilobed. Abdominal tergite II slightly eroded laterally in anterior 2/3. Posteromarginal setae on abdominal tergite IX sharply pointed, shorter than tube, S1 shorter than S2. Tube ( Fig. 81 ) longer than head, about 1.2 times as long as head, about 3.6 times as long as broad, almost straight-sided, weakly constricted at apex.

Measurements (female in μm). Body length about 5160 (distended). Head length 535, from anterior margin of eyes 510, width across cheeks just behind eyes 340; eyes length 125, width 90; postocular setae 210–250. Antenna total length 940, segments I–VIII length (width) as follows: 110 (62), 100 (53), 183 (52), 158 (52), 136 (50), 103 (44), 77 (33), 60 (23). Pronotum length 260, width 520. Setae on prothorax: am 40–90, aa?70–80, ml 130–230, pa 240, epim 300–330. Fore wing length 2320. Sub-basal wing setae: S1 140–145, S2 210–215, S3 230–240. Setae on tergite IX: S1 500, S2 550. Tube length 640, maximum width 180; terminal setae 330.

Male (macroptera). Distended body length: 4.0mm. Colour and structure very similar to female. Antennal segment III 3.15 times as long as broad. Pronotal aa much longer than am. Tube a little shorter than head, 0.97 times as long as head, distinctly swollen at base.

Measurements (male in μm). Body length about 4000 (distended). Head length 465, from anterior margin of eyes 440, width 295; eyes length 115, width 75; postocular setae 180. Antenna total length 750, segments I–VIII length (width) as follows: 85 (59), 80 (48), 148 (47), 135 (48), 115 (48), 80 (38), 62 (30), 50 (20). Pronotum length 232, width 450. Setae on prothorax: am 25–30, aa 100–120, ml?180, pa?200, epim 260. Fore wing length 1780. Sub-basal wing setae: S1 100–110, S2 175–180, S3 200–220. Setae on tergite IX: S1 340, S2 420. Tube length 450, maximum width 140; terminal setae 270.

Specimens examined. 1 female and 1 male, Laos, Houapan Prov. , Phu Pan, on dead leaves, 10.iv.2004, M. Hasegawa .

Remarks. This large species is presumably distinguished from its congeners by a combination of the following character states: postocular setae usually more than 200μm, situated behind inner margins of eyes; posterior ocelli slightly apart from eyes; antennal segment III more than 3.0 times as long as broad; cheeks with about 10 stout setae; fore femora with many long and slender setae; pelta trilobed.

Figures

FIGURES 77–83. Ethirothrips longisetis, female. (77) Outer portion of fore femur; (78) head & prothorax; (79) metanotum & pelta; (80) antennal segments III and IV; (81) tube; (82) mesopresternum; (83) fore tarsus.

FIGURES 223–234. Ethirothrips species, female. (223) E. longiceps sp. n.; (224) E. longisetis; (225) E. malaya sp. n.; (226) E. obscurus; (227) E. oculus sp. n.; (228) E. ommatus sp. n.; (229) E. puiensis sp. n.; (230) E. quadratus sp. n.; (231) E. rubeus, paratype; (232) E. rubeus from Thailand; (233) E. saigon sp. n.; (234) E. setosus sp. n.