Scirtothrips lami, Rachana & Amarendra & Sushil, 2024

Rachana, R. R., Amarendra, B. & Sushil, S. N., 2024, A new species and a new record of the genus Scirtothrips (Thysanoptera, Thripidae) from India, Zootaxa 5537 (3), pp. 424-430 : 425-428

Scirtothrips lami sp. nov.

( Figs 1–12 )

Female macroptera. Body pale ( Fig. 1 ), slightly shaded within ocellar triangle, on the pronotum, median area of abdominal tergites III–VII; medially dark antecostal ridges on tergites III–VIII and sternites III–VII ( Figs 7, 11&12 ); antennal segments I–II pale, III–VIII brown ( Fig. 5 ); fore wings shaded, apex pale; clavus shaded ( Fig. 9 ); legs pale; prominent body setae pale brown. Head wider than long with transverse striations; ocellar setae III situated between middle of hind ocelli; four pairs of postocular setae, S1 and S2 setae subequal to ocellar setae III, S3 setae minute, S4 setae arising laterally ( Fig. 4 ); mouth-cone small, not extending beyond posterior margin of pronotum. Antennae 8 segmented, segments III and IV with forked sense cone, just reaching one-third length of the succeeding segment; segment II with a mid-dorsal seta, with campaniform sensilla ( Fig. 5 ). Pronotum with closely spaced striae, space between sculpture lines as wide as diameter of socket of discal setae; posteromarginal setae four pairs, S2 setae twice as long as S1 ( Fig. 3 ). Mesonotum without campaniform sensilla anteromedially, median setae well ahead of posterior margin ( Fig. 6 ). Metascutum with transverse striations anteromedially, longitudinal striations medially and transverse reticulations posteromedially; median pair of setae placed behind the anterior margin, without campaniform sensilla ( Fig. 6 ). Mesosternal endofurca with spinula. Metasternal endofurca with slightly outcurved apex, with spinula. Fore wing first vein with 6–7 basal setae irregularly spaced and 3 setae on distal half, second vein with 2 setae; clavus with 4 veinal and 1 discal setae; posteromarginal and anteromarginal fringe cilia straight ( Fig. 9 ). Abdominal tergites II–IV with S1 setae close to each other, longer than their intervals but variable in length both between tergites and between individuals; tergites II–VII with posteromarginal microtrichia lateral to S2 setae, with 3 discal setae on lateral microtrichial fields of III–VII ( Fig. 12 ); tergite VIII with microtrichia anteromedially, having complete posteromarginal comb ( Fig. 7 ); tergite IX with microtrichia posteromedially but without CPS; tergite X without microtrichia ( Fig. 8 ); sternites III–VII with discal microtrichial rows lateral to S2 setae, rows below the anterior half extending to S1 setae diagonally, sternites without posteromarginal microtrichia; sternite II with 2 pairs of posteromarginal setae, III–VII with 3 pairs of posteromarginal setae; sternite VII with S1 setae slightly in front of posterior margin ( Fig. 11 ).

Measurements (holotype female in microns). Body length 950. Head, length 75; width across eyes 128; ocellar setae III 13; postocular setae I 13. Pronotum, length 95; width 145; posteromarginal setae I 15; posteromarginal setae II 33. Fore wing length 610. Antennal segments III–VIII length 43, 43, 35, 40, 8, 10.

Male macroptera. Similar in colour and sculpture to female, except body smaller ( Fig. 2 ); fore wing first vein with 6 basal setae, 2 setae on distal half; second vein with 1 seta; abdominal tergite IX without drepanae ( Fig. 10 ).

Measurements (paratype male in microns). Body length 730. Head, length 58; width across eyes 120; ocellar setae III 13; postocular setae I 13. Pronotum, length 78; width 115; posteromarginal setae I 15; posteromarginal setae II 33. Fore wing length 510. Antennal segments III–VIII length 35, 35, 30, 33, 8, 10.

Material studied. Holotype female, INDIA, Karnataka, Kemmanagundi , collected on leaves of unidentified plant ( Asteraceae ), 04.ii.2021 (Rachana R.R.) (ICAR/NBAIR/THYS/ 04022021 ) . Paratypes: 3 females and 1 male collected together with the holotype ; Karnataka, Shivamogga, from leaves of unidentified weed, 1 female, 09.i.2017 , 3 females, 06.ii.2021, Rachana R.R . Holotype and paratypes deposited in the National Insect Museum, National Bureau of Agricultural Insect Resources ( ICAR-NBAIR), Bengaluru, India.

Etymology: This species is named in recognition of the contributions of Laurence A. Mound to Thysanoptera taxonomy, and also for celebrating his ninetieth birthday.

Comments: According to the key to Scirtothrips species from Japan, the new species is similar to Scirtothrips pini Masumoto & Okajima, 2019 , and shares the position of ocellar setae III, abdominal tergite VIII with microtrichia anteromedially, tergites and sternites with antecostal ridges dark, and tergite IX with microtrichia. The new species differs from pini by the following characters: postocular setae subequal to ocellar setae III, two pairs of setae subequal in length, third pair setae minute (in pini postocular setae shorter than ocellar setae III, three pairs of setae subequal in length, no minute setae); tergite X without microtrichia (tergite X with microtrichia in pini ); sternites III–VII with discal microtrichial rows below the anterior half extending to S1 setae (in pini sternites III–VII with discal microtrichial rows not reaching to S1 setae); sternite VII with S1 setae submarginal (sternite VII with S1 setae marginal in pini ).

In comparison to available descriptions, this new species is superficially similar to S. asinus Wang, 1994 and S. flavus Masumoto & Okajima, 2007 . It can be distinguished from both of them by having mid-dorsal seta on segment II, microtrichia anteriomedially on abdominal tergite VIII, tergites not having posteromarginal vestigial microtrichia mesad of S2 setae, discal microtrichial rows below the anterior half of sternites III–VII extending to S1 setae. Moreover, male of the new species does not have drepanae on tergite IX.

Further,this species is close to Scirtothrips dobroskyi Moulton,1936 but it can be differentiated by posteromarginal setae II two times longer than posteromarginal setae I (three times in dobroskyi ), median tergal setae on III–V positioned posterior to a line joining discal setae (median tergal setae on III–V positioned anterior to a line joining discal setae in dobroskyi ), tergite VIII with discal microtrichia anteromedially (VIII without anteromedian discal microtrichia in dobroskyi ), sternites III–VII with discal microtrichial rows below the anterior half extending to S1 setae (sternites with discal microtrichia rows scarcely mesad of S 2 in dobroskyi ) males without drepanae on tergite IX (males with drepanae on tergite IX in dobroskyi ).

Scirtothrips ginkgoe Mirab-balou, Tong & Chen, 2012 can be distinguished from the new species by having pale antecostal ridge on abdominal tergites, posteromarginal setae II 1.6 times that of posteromarginal setae I and discal microtrichial rows extending fully across median area on posterior half of abdominal sternites.

Figures

FIGURES 1–6. Scirtothrips lami sp. nov. (1) Female; (2) Male; (3) Pronotum; (4) Head, dorsal; (5) Antenna; (6) Meso and metanotum.

FIGURES 7–12. Scirtothrips lami sp. nov. (7) Female abdominal tergite VIII; (8) Female abdominal tergites IX–X; (9) Fore wing; (10) Male abdominal tergites IX–X; (11) Female abdominal sternites V–VII; (12) Female abdominal tergites III–V.