Mycterothrips auratus Wang, 1999

Masumoto, Masami & Okajima, Shûji, 2024, Further study of the genus Mycterothrips Trybom (Thysanoptera: Thripidae) in Japan, with description of a new species and a new record, Zootaxa 5489 (1), pp. 107-124 : 118-120

Mycterothrips auratus Wang

( Figs 7, 8, 12 , 35–42 )

Mycterothrips auratus Wang, 1999: 232 .

Female macroptera. Body length 1.4–1.6 mm. Body yellow with pale brown markings on mesonotum, metascutum and abdominal tergites ( Fig. 7 ); antennal segment I yellow, II and IV – VIII brown, III pale brown with base pale; fore wings uniformly pale; all legs yellowish; major setae dark. Head 0.7–0.8 times as long as width, sculptured with transverse anastomosing striae; ocellar setae pair III situated between hind ocelli and near anterior margin of hind ocelli, about 4 times as long as their interval ( Fig. 35 ). Antennal segments III and IV with short apical neck, III straight at each side, IV slightly rounded at each side, IV and V pedicelate, VI not pedicellate, rounded basally and tapering distal two–thirds ( Fig. 37 ). Ratio length/width of antennal segments I– VIII as follows: 1.0, 1.4–1.5, 2.5– 2.9, 2.1–2.5, 1.5–1.8, 2.4, 0.8–1.1, 3.0–3.2. Pronotum about 0.8 times as long as width, sculptured with transverse anastomosing striae, with 43–48 discal setae; posteroangular setae pair I about 0.4 times as long as pronotal median length and almost as long as setae pair II; posteromarginal S1 setae about 0.3 times as long as pronotal median length and about twice as long as S2 setae. Mesonotum sculptured with widely spaced transverse anastomosing striae, without CPS anteromedially; median pair of setae near posterior margin. Metascutum irregularly reticulate medially; median pair of setae near anterior margin, about 0.7 times as long as metascutal median length. Fore wing first vein with 28–36 setae, second vein with 13–16 setae. Abdominal tergite I with S1 setae minute; tergite II with 4 lateral marginal setae; tergites II–VIII laterally with ciliate microtrichia, microtrichia much shorter than interval between sculpture lines, transverse striae exceeding S2 setae but not reaching median CPS on V–VII, with posteromarginal microtrichia outside of S2 setae on II–VII ( Fig. 39 ); tergite IX with two pairs or three (rarely one pair) of CPS; tergite X with longitudinal slit distally; sternites III (or IV)–VII (or VI) with a pair of (often only one or 3) discal setae near posterior margin ( Figs 40, 41 ); sternite VII with S1 setae in front of posterior margin; pleurotergites with ciliate microtrichia. Ovipositor 1.7–1.8 times as long as pronotal median length.

Male macroptera. Body length 0.9–1.1 mm. Body grayish brown ( Fig. 8 ); all antennal segments brown, segment I slightly paler than remaining segments; fore wings uniformly pale brown. Antennae 8-segmented, segment VI much elongated and with numerous long setae, 1.2–1.4 times as long as combined length of I–V, VII and VIII very small, IV about 0.7 times as long as III ( Fig. 38 ). Ratio length/width of antennal segments I–VIII as follows: 0.9, 1.4–1.6, 1.8–1.9, 1.2–1.3, 0.8, 8.1–8.4, 0.8–1.0, 1.5–2.0. Pronotum with about 30–34 discal setae ( Fig. 36 ). Fore wing first vein with 26–31 setae, second vein with 12–15 setae. Abdominal tergites without ciliate microtrichia; tergite II with 4 lateral marginal setae; tergite IX with S1 setae slightly behind S2 setae, a pair of minute setae near posterior margin ( Fig. 42 ); sternites IV–VIII with 1–5 discal setae. Hypomere dilated at apex.

Specimens examined. JAPAN: Ryukyus: Minamidaito-jima Is: 3 females on Morus australis [ Moraceae ], 20.iii.2008, K.Minoura. 1 male on vines (host unknown), 21.iii.2008, K.Minoura. Okinawa-hontou Is.: Kunigamison, Hedo, 1 female on Miscanthus sinensis [ Poaceae ], 20.iii.2005, K.Minoura. Uruma-shi, Hatsuren, Haebaru, 1 female on Poaceae , 21.i.2022, T.Yasuoka. Kume-jima Is, 1 female on bamboo leaf, 27.iv.2003, K.Minoura. Iriomote-jima Is., Omiya-rindou, 1 female (host unknown), 26.iii.2019, S.Okajima. All specimens are deposited in TUA. Paratypes: TAIWAN, Taoyuan, Tsurhu, 3 females & 2 males on Morus sp. , 7.v.1992, C.L.Wang (TARI) .

Comments. The original description of this species indicates that females have no ciliate microtrichia on the abdominal tergites, and Masumoto & Okajma (2006) accepted this statement having studies only paratypes without KOH treatment. However, in this study same paratypes were scrutinized again and ciliate microtrichia were recognized. Moreover, Masumoto & Okajima (2006) stated male antennal segment VI is 1.7 times as long as combined length of segments I– V but it is recognized as about 1.4 times in the present study. In Japanese specimens studied here, abdominal sternite VII usually lacks discal setae. This species is here newly recorded from Japan.

Figures

FIGURES 5–15. Mycterothrips species, slide-mounted specimens. Adult 5–11. M. albiziae sp. n.: (5) Female; (6) Male. M. auratus: (7) Female; (8) Male. M. glycines: (9) Female; (10) Female, dark type; (11) Male. Second instar larvae, 12–15: (12) M. albiziae, sp. n.; (13) M. fasciatus; (14) M. glycines; (15) M. japonicus.

FIGURES 35–38. Mycterothrips auratus. Head, 35–36: (35) Female; (36) Male. Antenna, 37–38; (37) Female; (38) Male.

FIGURES 39–42. Mycterothrips auratus, abdominal segments, female, 39–41: (39) Tergites VII–X; (40) Sternites V–VII; (41) Sternites IV–VI. (42) Abdominal tergite IX and apex of hypomere, male. hy=hypomere. (39 & 40, paratype; others, Okinawa)