Scirtothrips flavus, 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 : 27-28

Scirtothrips flavus n. sp.

( Figs. 10 A, 12A & F, 14A, 15B & 17C)

Scirtothrips sp., Okajima, 2000: 102.

Female. Distended body length 1.1–1.2 mm. Body uniformly yellowish white; antennal segment I to II pale, III pale brown with pedicel pale, IV to V pale brown with extreme base barely pale, VI to VIII pale brown; fore wings pale with base including clavus barely shaded; all legs yellowish white; prominent body setae pale.

Head 1.8–2.6 times as wide as long. Ocellar setae III situated at tangent of anterior margin of hind ocelli ( Fig. 10 A). Two pairs of postocular setae mesad of compound eyes slightly shorter than ocellar setae III, these setae somewhat unstable and often absent on one side, minute setae often present between two these setae. Compound eyes without pigmented ommatidia. Antennae 8-segmented, segment II without mid-dorsal seta below CPS, III the longest, barely widest near apex and nearly straight at each side ( Fig. 12 A). Antennal segments I to VIII length/width ratio as follows: 0.8, 1.3–1.4, 2.5–2.9, 2.3–2.6, 2.2–2.3, 2.9–3.2, 0.8–1.2, 2.5.

Pronotum 1.5–1.7times as wide as long, space between lines of sculpture as wide as diameter of socket of discal setae, with 14–16 discal setae (including anteromarginals and lateralmarginals) (16 in the holotype); posteromarginal setae four pairs, B2 setae 0.1–0.4 times as long as pronotal median length and 2.2–2.6 times as long as B1 setae ( Fig. 10 A). Mesonotum without CPS anteromedially. Metascutum sculptured with equiangular or longitudinal oblong reticulations medially, smooth within reticulations; median pair of setae situated behind anterior margin ( Fig. 12 F). Fore wings with 25–28 setae on costal vein (26 on left, 27 on right, in the holotype), with five to six basal and three to four distal setae on first vein (five and three on left, five and four on right, in the holotype), with two or three setae on second vein; clavus with four veinal and one discal setae; posteromarginal fringe hair slightly wavy, not straight.

Abdominal terga with B1 setae slightly wide apart together than their length and slightly smaller than B2 setae on terga II to VI, lateral microtrichial fields each with three discal setae ( Fig. 14 A); terga II to VII with posteromarginal microtrichia at out side of B2 setae and with vestigial very small posteromarginal microtrichia between B1 setae and B2 setae; terga VIII without microtrichia anteromedially ( Fig. 15 B); tergum IX without microtrichia ( Fig. 15 B), with B1 setae, B2 setae and B3 setae each 0.9–1.0 times, 1.0–1.1 times and 0.8–1.0 times as long as median length of the tergum; tergum X without microtrichia ( Fig. 15 B), B1 setae and B2 setae each 1.5–1.7 times and 1.4–1.6 times as long as median length of the tergum; sterna with discal microtrichial rows at out side of B2 setae ( Fig. 17 C); sternum VII with B1 setae slightly in front of posterior margin. Ovipositor 2.0–2.3 times as long as pronotal median length.

Measurements of holotype female in microns. Distended body length 1150. Head length 73, width across cheeks 133; compound dorsal length 53, width 43. Pronotal median length 93, width 155; posteromarginal setae I length 15, setae II length 33–35. Metascutal median length 68, median setae length 16–18. Fore wings length 730, width at middle 30. Abdominal tergum IX median length 70; B1 setae length 65–68, B2 setae length 73, B3 setae length 55–58, mid-dorsal setae length 43–45; tergum X median length 40, B1 setae length 68, B2 setae length 63–65. Ovipositor length 210. Antennal segments I to VIII length (width) as follows: 20 (25), 35 (26), 48 (19), 43 (19), 38 (16), 48 (15), 6 (8), 13 (5).

Male. Unknown.

Type series. Holotype female: Japan, Honshu, Tokyo, The Imperial Palace, Fukiage-gyoen, host unknown, 15-v-1996, S. Okajima. Paratypes: 5 females collected together with the holotype. The holotype and paratypes are deposited in Laboratory of Entomology, TUA, Atsugi, Japan.

Etymology. In reference to body colour of the species.

Comments. This species is very similar to S. albidus described above, but it can be distinguished from the latter species by short postocular and pronotal posteromarginal setae and by the key above.

Figures

FIGURE 10. Scirtothrips species, head & pronotum (female). (A) S. flavus n. sp.; (B) S. katsura n. sp.

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 14. Scirtothrips species, abdominal terga (female). (A) S. flavus n. sp., right side of tergum V; (B) S. katsura n. sp., tergum VI (microtrichial row omitted on left side.).

FIGURE 15. Scirtothrips species, terminal abdominal terga (female). (A) S. albidus n. sp., terga VIII – X (microtrichial row omitted on left side of tergum VIII); (B) S. flavus 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.).