Scirtothrips machili, Masumoto, Masami & Okajima, Shûji, 2007

Masumoto, Masami & Okajima, Shûji, 2007, The genus Scirtothrips Shull (Insecta, Thysanoptera, Thripidae) and three related genera in Japan, Zootaxa 1552, pp. 1-33 : 30-32

Scirtothrips machili n. sp.

( Figs. 11 A, 12C, 13B, 16B, 17E, 18A & D)

Female. Distended body length 0.9–1.0 mm. Body grayish yellow, head shaded within ocellar triangle and brown apex of frons, pronotum shaded at laterally and posteromedially, abdominal terga III to VII slightly shaded on laterally, terga III to VIII dark at antecostal ridge; antennal segment I pale, II pale brown, III to V brown with extreme base barely pale, VI to VIII brown; fore wings shaded with distal half slightly paler; all legs yellow or barely shaded; prominent body setae brown.

Head 1.7–2.3 times as wide as long. Ocellar setae III situated between middle of hind ocelli ( Fig. 11 A). One pair of postocular setae mesad of compound eyes almost as long as ocellar setae III. Compound eyes without pigmented ommatidia. Antennae 8-segmented, segment II slightly bulged near apex of inner margin, III the longest, barely widest near apex and gently rounded at each side ( Fig. 12 C). Antennal segments I to VIII length/width ratio as follows: 1.0–1.4, 1.1–1.5, 2.1–2.5, 2.1–2.5, 2.2–2.5, 2.6–3.0, 1.0–1.4, 2.3–3.3.

Pronotum 1.6–1.9 times as wide as long, space between lines of sculpture as wide as or narrower than diameter of socket of discal setae, with 15–19 discal setae (including anteromarginals and lateralmarginals) (18 in the holotype); posteromarginal setae four pairs, B2 setae 0.5 times as long as pronotal median length and 1.5–2.0 times as long as B1 setae ( Fig. 11 A). Mesonotum without CPS anteromedially. Metascutum sculptured with longitudinal oblong reticulations medially, smooth within reticulations; median pair of setae situated behind anterior margin ( Fig. 13 B) Metathoracic furca recurved to each side at apex ( Fig. 18 A). Fore wings with 21–26 setae on costal vein (25 on left, 24 on right, in the holotype), with five to eight basal and three or four distal setae on first vein (six and three in the holotype), with one (rarely no) seta on second vein; clavus with three veinal and one discal setae; antero- and posteromarginal fringe cilia straight.

Abdominal terga B1 setae closer together than their length, especially on III to V, lateral microtrichial fields each with three setae; terga II to VII with posteromarginal microtrichia at out side of B2 setae; tergum VIII with microtrichia anteromedially ( Fig. 16 B); tergum IX with microtrichia at middle ( Fig. 16 B), B1 setae, B2 setae and B3 setae each 0.8–0.9, 0.9–1.1 and 0.8–1.0 times as long as median length of the tergum; tergum X with some microtrichial rows medially ( Fig. 16 B), B1 setae and B2 setae each 1.0–1.3 and 1.1–1.3 times as long as median length of the tergum; sterna with discal microtrichial rows at out side of B1 setae ( Fig. 17 E); sternum VII with B1 setae slightly in front of posterior margin. Ovipositor 1.8–2.0 times as long as pronotal median length.

Measurements of holotype female in microns. Distended body length 1010. Head length 55, width across cheeks 128; compound dorsal length 50, width 38. Pronotal median length 90, width 150; posteromarginal setae I length 25–30, setae II length 41–44. Metascutal median length 70, median setae length 25. Fore wings length 600, width at middle 35. Abdominal tergum IX median length 62; B1 setae length 48, B2 setae length 58–60, B3 setae length 43–48, mid-dorsal setae length 40; tergum X median length 44, B1 setae length 43–48, B2 setae length 50–53. Ovipositor length 170. Antennal segments I to VIII length (width) as follows: 28 (23), 35 (25), 43 (19), 36 (18), 38 (15), 38 (14), 8 (6), 11 (5).

Male. Distended body length 0.7–0.8 mm. Body colour as in female. Abdominal tergum IX without drepanae and with a pair of setae on near posterior margin ( Fig. 18 D).

Measurements of paratype males in microns. Distended body length 740–760. Head length 50–51, width across cheeks 113–120; compound dorsal length 45–48, width 35. Pronotal median length 73–75, width 135– 138; posteromarginal setae I length 20–23, setae II length 35–38. Metascutal median length 60–63, median setae length 18–20. Fore wings length 410–440, width at middle 30. Antennal segments I to VIII length (width) as follows: 23 (20–21), 30 (25), 40 (18), 38 (18), 33 (18), 35–36 (15), 5–8 (8), 10–13 (5).

Type series. Holotype female: Japan, Honshu, Kanagawa Pref., Yokosuka City, Kannonzaki, on leaves of Machilus thunbergii [ Lauraceae ], 25-vi-2006, M. Masumoto. Paratypes: 12 females, 2 males, collected together with the holotype. 20 females, same host plant and locality as holotype, 29-vi-2002, M. Masumoto.

Non-paratypic specimens: Ryukyu Is. 1 female, Okinawa Pref., Ishigaki-jima Is., Takeda-rindou, host unknown, 16-i-1991, S. Okajima. 4 females, Okinawa Pref., Ishigaki-jima Is., Shiramizu, host unknown (yellow pan trap), 5-x-2004, M. Sato & T. Ishizaki. 1 female, Okinawa Pref., Ishigaki-jima Is., Mt. Banna-dake, host unknown (unidentified), 1-iv-1999, T. Tsutsumi (FU). 1 female, Okinawa Pref., Ishigaki-jima Is., Takeda-rindou, nr. Mt. Omoto-dake, host unknown (unidentified), 3-iv-1999, T. Tsutsumi (FU). 1 female, Okinawa Pref., Ishigaki-jima Is., Takeda-rindou, nr. Mt. Omoto-dake, host unknown (unidentified), 3-iv- 1999, T. Tsutsumi (FU). Okinawa Pref., Iriomote-jima Is., nr. Ohtomi, Nakamagawa-rindou, host unknown (leaf litter), 3-ix-1988, S. Okajima. 9 females, Okinawa Pref., Yonaguni-jima Is., Mantabaru-rindou, host unknown, 5-iv-1999, T. Tsutsumi (FU). 26 females, 3 males, Okinawa Pref., Yonaguni-jima Is., Mantabarurindou, host unknown (unidentified), 5-iv-1999, T. Tsutsumi (FU). 7 females, 1 male, Okinawa Pref., Yonaguni-jima Is., Mantabaru-rindou, on Styrax japonica [ Styracaceae ], 5-iv-1999, T. Tsutsumi (FU). 4 females, Okinawa Pref., Yonaguni-jima Is., Mantabaru-rindou, host unknown (unidentified), 5-iv-1999, T. Tsutsumi (FU). 3 females, Okinawa Pref., Yonaguni-jima Is., Mantabaru-rindou, host unknown (unidentified), 5-iv- 1999, T. Tsutsumi (FU). 7 females, 2 males, Okinawa Pref., Yonaguni-jima Is., Mantabaru-rindou, on Poaceae , 5-iv-1999, T. Tsutsumi (FU). 3 females, 1 male, Okinawa Pref., Yonaguni-jima Is., Mantabaru-rindou, on leaves of Arenga engleri [Palmaceae], 5-iv-1999, T. Tsutsumi (FU). 38 females, Okinawa Pref., Yonaguni-jima Is., Mantabaru-rindou, host unknown (unidentified), 5-iv-1999, T. Tsutsumi (FU). 13 females, 2 males, Okinawa Pref., Yonaguni-jima Is., Mantabaru-rindou, host unknown (unidentified), 5-iv-1999, T. Tsutsumi (FU). 7 female, 1 male, Okinawa Pref., Yonaguni-jima Is., Mantabaru-rindou, Miscanthus sinensis [ Poaceae ], 5-iv-1999, T. Tsutsumi (FU). 31 females, 17 males, Okinawa Pref., Yonaguni-jima Is., western area of Mt. Urabu-dake, host unknown (unidentified), 6-iv-1999, T. Tsutsumi (FU). 7 females, 1 male, Okinawa Pref., Yonaguni-jima Is., western area of Mt. Urabu-dake, on Poaceae , 6-iv-1999, T. Tsutsumi (FU). 2 females, Okinawa Pref., Yonaguni-jima Is., western area of Mt. Urabu-dake, on bamboo leaves, 6-iv-1999, T. Tsutsumi (FU). 27 females, Okinawa Pref., Yonaguni-jima Is., western area of Mt. Urabu-dake, host unknown (unidentified), 6-iv-1999, T. Tsutsumi (FU). 1 females, Okinawa Pref., Yonaguni-jima Is., Mantabaru, near Shinrin-kouen park, on Moraceae , 5-iv-1999, T. Tsutsumi (FU). Kyushu 10 females, Kagoshima Pref., Yakushima Is., Mugio, young buds of Machilus thunbergii [ Lauraceae ], 10-iii-2000, T. Tsutsumi (FU). 3 females, Kagoshima Pref., Yaku-shima Is., Onoaida, on flowers of Machilus thunbergii , 12-iii-2000, T. Tsutsumi (FU). 2 females, 1 male, Kagoshima Pref., Yaku-shima Is., Ohko, on flowers of Ardisia sieboldii [ Myrsinaceae ], 12- iii-2000, T. Tsutsumi (FU). Izu-shotou Is. 1 female, Tokyo-to, Miyake-jima is., Tsubota, on Ligustrum ovalifolium var. pacificum [ Oleaceae ], 15-v-1999, S. Okajima. The holotype and most paratypes are deposited in Laboratory of Entomology, TUA, Atsugi, Japan.

Etymology. In reference to the host plant of the species.

Comments. This species can be distinguished by the body colour and unique shape of the metathoracic spinula. The male of S. machili is very similar to that of S. dorsalis , but the latter has no microtrichia on female tergum X and no setae on or near the posterior margin of male tergum IX ( Fig. 18 B).

Figures

FIGURE 11. Scirtothrips species (female). (A) S. machili n. sp., Head & pronotum; B – C, Antenna: (B) S. albidus n. sp.; (C) S. dorsalis.

FIGURE 12. Scirtothrips species (female). A – C, Antenna: (A) S. flavus n. sp.; (B) S. katsura n. sp.; (C) S. machili n. sp., (D) S. albidus n. sp., mesonotum & metascutum. E – F, Metascutum: (E) S. dorsalis; (F) S. flavus n. sp.

FIGURE 13. Scirtothrips species (female). A – B, Metascutum: (A) S. katsura n. sp.; (B) S. machili n. sp. C – E, Abdominal terga: (C) S. albidus n. sp., tergum VI (microtrichial row omitted on left side); (D) S. albidus n. sp., tergum VII (microtrichial row omitted on left side); (E) S. dorsalis, left side of tergum VI (microtrichial row omitted.).

FIGURE 16. Scirtothrips species, terminal abdominal terga (female). (A) S. katsura n. sp., terga VIII – XI; (B) S. machili n. sp., terga VIII – XI (microtrichial row omitted on left side of tergum VIII).

FIGURE 17. Scirtothrips species, abdominal sternum (female). (A) S. albidus n. sp., sternum VII; (B) S. dorsalis, sternum VI (microtrichial row omitted on left side.); (C) S. flavus n. sp., right side of sternum VI; (D) S. katsura n. sp., sternum VI (microtrichial row omitted on left side.); (E) S. machili n. sp. sternum V (microtrichial row omitted on left side.).

FIGURE 18. Scirtothrips species. (A) S. machili n. sp., Female (ventral aspect of thorax). B – D, Male abdominal terga: (B) S. dorsalis, tergum IX; (C) S. katsura n. sp., tergum IX (sculpture omitted.); (D) S. machili n. sp., terga IX – X (sculpture omitted.).