Parabaliothrips brevisetosus, Masumoto & Okajima, 2020

Masumoto, Masami & Okajima, Shûji, 2020, The genus Parabaliothrips Priesner (Thysanoptera, Thripidae) with three new species from Japan and Taiwan, and two new records of related genera from Japan, Zootaxa 4838 (4), pp. 566-580 : 573-576

Parabaliothrips brevisetosus n. sp.

( Figs 6 , 26–35 )

Female macroptera. Distended body length 1.7–1.8 mm. Body uniformly dark brown with red internal pigment ( Fig. 6 ); antennal segment I–II dark brown, III–IV yellow, V yellow with distal half shaded, IV–VIII brown; fore wings brown but pale near base and apex, clavus brown; all femora dark brown, fore tibiae brown with distal third yellowish, mid and hind tibiae dark brown, all tarsi yellow to brownish yellow; prominent body setae dark brown. Head 0.7–0.8 times as long as wide, slightly prolonged anteriorly; cheeks straight ( Fig. 26 ). Ocellar setae III situated at or just behind tangent line of posterior margin of hind ocelli, 2.3–3.3 times as long as their interval. Postocular setae 4 pairs, setae II absent, III subequal length to IV and slightly shorter than V. Antennal segment II without microtrichial rows, inner dorsal seta much longer than outer one, III widest near apex and weakly tapering to apex as neck, IV gently rounded at each side, longest, IV–V pedicelate, VI gently rounded at basal half and weakly tapering to apex ( Fig. 27 ). Antennal segments I–VIII length/width ratio as follows: 0.7–1.2, 1.3–1.5, 2.7–2.9, 2.4–2.7, 1.8–2.2, 2.0–2.4, 1.2–1.3, 2.3–2.8. Pronotum about 0.6 times as long as wide, weakly sculptured medially, with 6 discal setae medially, anteroangular and anteromarginal setae not developed, but a pair of anteromarginals often slightly longer than discal setae; posteroangular setae I 0.7–0.8 times as long as pronotal median length and longer than setae II; posteromarginal setae 3 pairs, setae I 0.1–0.3 times as long as pronotal median length, much longer than remaining setae. Mesonotum without CPS anteromedially ( Fig. 28 ). Metascutum smooth medially, with median pair of setae 0.5–0.7 times as long as metascutal median length. Mesosternal spinula absent. Clavus with subapical setae not longer than apical setae on vein. Fore tibiae with 2 stout ventroapical setae. Abdominal tergites laterally with lines of sculpture, some weak lines across middle anterior to S1 setae, very weak sculpture between S1 setae ( Fig. 29 ); tergites VII–VIII with S1 setae longer than that of anterior tergites; tergite VIII without long gap of posteromarginal comb but irregularly spaced, microtrichia weak; tergite IX with both anterior and posterior pairs of CPS ( Fig. 30 ); pleurosternites with posteromarginal craspeda having small but distinctly pointed distal teeth. Ovipositor 2.4–2.5 times as long as pronotal median length.

Measurements (holotype female in microns). Distended body length 1780. Head length 124 (length including anterior prolongation 143), width across cheeks 175; compound eyes dorsal length 70, width 45. Ocellar setae III length71–76, interval 25. Postocular setae III length 15, setae V length 15–24. Pronotal median length 140, width 238; posteroangular setae I length 95–100, setae II length 86, posteromarginal setae I length 30–33. Metascutal median length 95, median setae length 61–63. Fore wing length 920, width at middle 70. Ovipositor length 340. Antennal segments I to VIII length (wide) as follows: 33 (38), 45 (33), 65 (23), 56 (21), 41 (19), 49 (21), 15 (11), 18 (6).

Male. Unknown.

First instar larva. Body with internal reddish pink pigments ( Fig. 31 ), head with grey markings along internal margin of antennal socket, laterally anterior to eyes ( Fig. 32 ), pronotum with grey markings, mesonotum with grey spots on base of D1 and D2 setae, metanotum with grey spots on D1 setae and between D1 and D5 setae, abdominal tergites with small grey spots on setae bases, tergite VIII with narrow grey band along posterior margin ( Fig. 35 ), tergite X dark; antennal segment I grey internal half dorsally, II-VII pale grey ( Fig. 33 ). Head smooth, with 4 pairs of dorsal setae, D1 setae minute, D2 longest and slightly longer than D4, D4 much longer than D3. Antennae 7-segmented, setae much elongate, setae on segments II longer than this segment, III without microtrichia, IV with microtrichia, V and VI not united. Pronotum smooth and with 6 pairs setae, D1, D2 and D5 setae subequal in length and much shorter than D7, D3 and D4 setae minute, D4 much shorter than D2, D5 much elongate and more than twice as long as D1; meso and metanota with small scattered granules, each with 5 pairs of setae. Abdominal tergites I–VIII with a few rows of scattered granules, dorsal setae longer than half of tergal length ( Fig. 34 ); tergite IX with small teeth along posterior margin, about 3 rows of granules along posterior margin, median CPS apart from each other about 1.6 times as wide as interval of D1 setae, D2 setae much elongate and about 2.5 times as long as D1 setae; sternites with scattered granules as tergites. Spiracle on mesonotum relatively large and circular, but small on tergites II and VIII.

Type series. Holotype female, JAPAN, Honshu, Kanagawa-ken, Hayama-cho, Mt. Futago-yama, on young leaf of Castanopsis sieboldii [ Fagaceae ], 1.v.2016, M. Masumoto. Paratypes: Honshu: 23 females, collected together with holotype. Same place and plants as holotype: 2 females, 15.v.2005, M. Masumoto. Kanagawa-ken, Yokosukashi, Kannonzaki: 5 females on leaf of Castanopsis sieboldii , 14.v.2006; 1 female on leaf of Morus bombycis [ Moraceae ], 21.v.2006; 12 females on young leaf of Castanopsis sieboldii , 19.v.2019; Yokosuka-shi, Kurihama-hananokuni park, 4 females on leaf of Castanopsis sieboldii , 12.v.2019; all M. Masumoto. Kanagawa-ken, Yokosuka-shi, Mt. Takatori-yama: 79 females on flower of Castanopsis sieboldii , 8.v.2015; 15 females on flower of Castanopsis sieboldii , 30.iv.2016; 53 females on flower of Castanopsis sieboldii , 5.v.2016; 10 females on flower of Castanopsis sieboldii , 4.v.2018; 1 female on flower of Castanopsis sieboldii , 29.iv.2019; 1 female on young leaf of Wisteria floribunda [Leguminosae], 5.v.2016; all M. Masumoto. Kanagawa-ken, Zushi-shi, Jinmuji, 1 female, host unknown (sweeping), 22.v.1976, S. Okajima. Chiba-ken, Sakae-machi, 1 female on leaf of Pteridium aquilinum [ Pteridaceae ], 26.v.2003, Y. Yoshida. Chiba-ken, Futtsu-shi, foot of Mt. Nokogiri-yama: 4 females on flower & young leaf of Castanopsis sieboldii , 5.v.2013; 1 female of on leaf of Cinnamomum japonicum [ Lauraceae ], 5.v.2013; all M. Masumoto. Ibaraki-ken, Kasumigaura-shi, Mitsuishi-shinrinkouen park, 4 females on leaf of Magnolia kobus [ Magnoliaceae ], 3.v.2013, M. Masumoto. The holotype and most paratypes are deposited in TUA.

Non paratypic specimens. Honshu: Kanagawa-ken , Yokosuka-shi , Mt. Takatori-yama : 2 first instar larva on flower of Castanopsis sieboldii , 29.iv.2019, M. Masumoto. Kyushu: Fukuoka-ken , Mt. Tachibana, 3 females on yellow pan trap, 16.vi.1979, K. Yamagishi. Yamaguchi-ken, Hagi-shi, Mt. Shizuki-yama, 2 females, host unknown, 29.iv.2013, T. Sugimoto. Ryukyus: Kagoshima-ken , Amami-ohshima Is., Uken-son , Fureainomori, 1 female on dead leaves and branches, 28.iii.1990, S. Okajima. Okinawa-ken, Okinawa-hontou Is., Kunigami-son, Mt. Yonahadake, 4 females, host unknown, 4.iv.1990, T. Nonaka. All are deposited in TUA .

Comments. This new species was referred to as undescribed species by Gillespie et al. (2002). It is similar to the Australian species in lacking long postocular setae and long anteromarginal setae on the pronotum, but is distinguished from the Australian species in the key above. Numerous individuals of this species including first instar larvae are associated with flowers of Castanopsis sieboldii , but the holotype and some paratypes were collected from young leaves of Fagaceae and other families. It may be the pollinator of Castanopsis sieboldii .

Etymology. In reference to their short pronotal setae.

Figures

FIGURES 1–8. Frankliniella genus-group. (1) Firmothrips firmus. Iridothrips mariae 2–3: (2) Female; (3) Male. Parabaliothrips betulaceae n. sp. 4–5: (4) Female; (5) Male. (6) P. brevisetosus n. sp. P. robustus n. sp. 7–8: (7) Female; (8) Male.

FIGURES 26–30. Parabaliothrips brevisetosus n. sp., female. (26) Head & pronotum; (27) Antenna; (28) Mesonotum & metascutum. Abdominal segments 29–30: (29) Tergites V–VI; (30) Tergites VIII–X, sculpture omitted.

FIGURES 31–35. Parabaliothrips brevisetosus n. sp., first instar larva. (31) Dorsal aspect; (32) Head & mesonotum; (33) Antenna. Abdominal segments 34–35: (34) Tergites VII–VIII; (35) Tergites IX–X.