Scolothrips asura Ramakrishna & Margabandhu

Masumoto, Masami, Ohno, Suguru, Ganaha-Kikumura, Tomoko, Miyagi, Akiko & Okajima, Shûji, 2012, Review of the genus Scolothrips (Insecta, Thysanoptera, Thripidae) from Japan, Zootaxa 3183 (1), pp. 36-48 : 38-41

Scolothrips asura Ramakrishna & Margabandhu

( Figs. 1 A −E & 2A −F)

Scolothrips asura Ramakrishna & Margabandhu, 1931: 1035 ; Bhatti, 1990; Wang, 2002: 254; Mound & Tree, 2007: 10; Mound, 2011: 47 .

Scolothrips azura (sic!); Priesner, 1950: 56.

Scolothrips quadrinotata Han & Zhang 1982: 56 . [Synonymized by Mound, 2011: 47]

Female macroptera. Distended body length 1.0− 1.2 mm. Body strongly bicoloured, with red internal pigments before KOH treatment, head brown but slightly paler posteromedially, pronotum white, mesothorax to abdominal segment II and segments VI −VIII dark brown, III −V white, IX −X pale brown; antennal segment I pale brown, II brown, III −IV white, V white with distal half slightly greyish, VI −VIII slightly greyish; fore wing ( Fig. 2 A) with two hyaline areas, dark brown at basal third including clavus and subdistal area, distal dark band half length of basal band, hyaline at median third and apex; all legs white; prominent body setae pale to slightly shaded except veinal setae dark on dark bands of fore wing.

Head ( Fig. 1 A) 0.6−0.8 times as long as wide. Ocellar setae III on ocellar hump and in front of hind ocelli. Antennal segment ( Fig. 1 B) III widest at middle, VI widest at basal third, III and IV without distal neck, VI and V slightly pedicelate, VI the longest, widest near base and tapering to apex, microtrichial row present on ventral surface of III and both dorsal and ventral surfaces of IV −VI. Antennal segments I −VIII length/width ratio as follows: 0.6−0.7, 0.9−1.2, 1.4−1.9, 1.3−2.0, 1.6−2.1, 2.3−2.8, 1.3−1.7, 2.0−2.5.

Pronotum ( Fig. 1 A) about 0.7 times as long as wide, with indistinct groove-like transverse lines of sculpture, without discal setae; major setae 0.8−1.4 times as long as pronotal median length.

Mesonotum sculptured with narrow spaced transverse anastomosing striae on posterior half; CPS absent anteromedially. Metascutum ( Fig. 1 C) sculptured with narrow spaced longitudinal anastomosing striae; median pair of setae close to lateral setae, 0.5−0.8 times as long as metascutal median length; CPS absent. Fore wing costal vein with 14−19 setae, first vein with 8−10 setae.

Abdominal tergites ( Figs. 1 E & 2B −C) I −III distinctly sculptured with narrow spaced transverse anastomosing lines of sculpture, but smooth submedian areas, IV −VIII laterally with similar sculpture slightly extending mesad of S2 setae, not reaching median CPS; tergite IX with posterior pair of CPS only, only lateral minor setae (SS3) present and small, 0.1−0.4 times as long as median length of the tergite; sternite VII ( Fig. 2 D) with S1 setae in front of posterior margin. Ovipositor 2.0−2.3 times as long as pronotal median length.

Measurements (female in microns). Body length 960−1190. Head length 65−93 (length including anterior prolongation 72−105), width across cheeks 105−118; compound eye dorsal length 43−68, width 35−45. Ocellar setae III length 77−105, distance between their bases 20−23. Pronotal median length 95−113, width 140; anteromarginal setae length 100−150, anteroangular setae length 88−140, posteroangular setae I length 80−127, setae II length 75−119; posteromarginal setae I length 86−121, ML setae length 70−125. Metascutal median length 55−65; median setae length 25−50. Fore wing length 520−700, width at middle 40−55. Abdominal tergite IX median length 73−83; S1 setae length 50−65, S2 seta length 55−85, S3 setae length 61−108, MD setae length 21−28, SS3 setae length 10−30; tergite X median length 48−58, S1 setae length 60−100, S2 setae 49−90. Ovipositor length 210−240. Antennal segments I −VIII length (width) 15−19 (24−30), 25−35 (25−30), 30−41 (20−25), 30−40 (19−23), 28−35 (15−18), 38−45 (16−19), 10−13 (8−9), 10−13 (5−6).

Male macroptera. Body colour similar to female, but terminal segment yellow. Abdominal tergite IX ( Fig. 2 E) without MD setae, S1 setae much ahead of level of S2 setae; sternite VIII ( Fig. 2 F) rarely with a few additional setae other than three posteromarginal setae; sternal pore plates 78−103 µm wide.

Measurements (male in microns). Body length 930. Head length 64 (length including anterior prolongation 74), width across cheeks 85; compound eye dorsal length 53, width 35. Ocellar setae III length 73−81, distance between their bases 15. Pronotal median length 88, width 128; anteromarginal setae length 90−95, anteroangular setae length 80−82, posteroangular setae I length 79−81, setae II length 72−73; posteromarginal setae I length 78−86, ML setae length 68−79. Metascutal median length 50; median setae length 25−28. Fore wing length 460, width at middle 40. Antennal segments I −VIII length (width) 20 (25), 25 (24), 35 (19), 30 (18), 25 (15), 37 (15), 10 (8), 10 (5).

Specimens examined. JAPAN, Ryukyus: Okinawa-hontou Island, 42 females; Ie-jima Island, 10 females; Miyako-jima Island, 9 females; Shimoji-jima Island, 3 females; Irabu-jima Island, 2 females; Ishigaki-jima Island, 1 male. TAIWAN, 15 females, 4 males. THAILAND, 16 females, 5 males.

Distribution. Japan: Ryukyus (Okinawa-hontou, Ie-jima, Miyako-jima, Shimoji-jima, Irabu-jima, Ishigakijima); Thailand; Taiwan; India; Australia.

Possible prey species. The following spider mite species were identified with S. asura in the Ryukyus and Taiwan: Eutetranychus africanus, Oligonichus biharensis, O. coffeae, Panonychus citri , Tetranychus evansi , T. kanzawai , T. neocaledonicus , T. okinawanus , T. piercei , T. pueraricola .

Comments. This species is similar to the Australian species, S. ochoa Mound et al. , in the bicoloured body and longitudinal sculpture lines on the metascutum, and they can be distinguished from all other members of the genus by their bicoloured body. S. ochoa is unique in this genus as follows; pronotum without mid-lateral setae, and head without anteocellar setae, and short antennal segments ( Mound et al., 2010).

Figures

FIGURE 1. Scolothrips asura, female. A, Head and pronotum; B, antenna, right; C, metascutum; D, prosternal ferna and prospinasternum; E, tergites I – II (right side omitted). Scales: 0.04 mm.

FIGURE 2. Scolothrips asura, female (A − D) and male (E − F). A, Fore wing, right (marginal fringe hairs omitted); B, tergite VI, right side; C, tergites VIII-X; D, sternite VII; E, tergite IX (MD setae irregularly lost); F, sternites VII – VIII (sculpture omitted, VIII with additional setae). Scales: 0.04 mm.