Scirtothrips donumdei, Rachana & Amarendra & Gracy & Nagarjuna Reddy & Sushil, 2024

Rachana, R. R., Amarendra, B., Gracy, R. Gandhi, Nagarjuna Reddy, K. V. & Sushil, S. N., 2024, A new species of the genus Scirtothrips (Thysanoptera, Thripidae) from India, Zootaxa 5397 (3), pp. 435-443 : 437-440

Scirtothrips donumdei sp. n.

( Figs 1–12 )

Female macroptera. Body pale ( Fig. 1 ), slightly shaded on the pronotum, lateral sides of the meso and metanota; abdominal tergites III–VII with median brown area not extending laterally to setal pair S2; tergites III–VIII and sternites III–VII with medially dark antecostal ridges ( Figs 11&12 ); antennal segments I–II pale, III–VIII brown ( Fig. 4 ); fore wings shaded, apex pale; clavus shaded ( Fig. 9 ); legs pale, but slightly shaded on outer surfaces of femur and tibiae; prominent body setae pale brown. Head wider than long with transverse striations; ocellar setae III situated close to fore ocellus on the tangent between fore and hind ocelli; four pairs of postocular setae, setae I and II equal to or slightly longer than ocellar setae III, setae III minute, setae IV arising laterally and shorter than I and II ( Fig. 5 ); 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 middorsal seta, without campaniform sensilla ( Fig. 4 ). Pronotum with closely spaced striae, space between sculpture lines as wide as diameter of socket of discal setae; posteromarginal setae four pairs, S2 setae 1.3 times as long as S1 ( Fig. 7 ). Mesonotum without campaniform sensilla anteromedially, median setae well ahead of posterior margin ( Fig. 3 ). Metascutum with transverse striations anteromedially, longitudinal reticulations medially and transverse reticulations posteromedially; median pair of setae near or at the anterior margin, without campaniform sensilla ( Fig. 3 ). Mesosternal endofurca with trifid apex, without spinula ( Fig. 6 ). Metasternal endofurca with slightly outcurved apex, with spinula ( Fig. 6 ). Fore wing first vein with 8–11 basal setae irregularly spaced and 3–7 setae on distal half, second vein with 2–3 setae; clavus with 3–4 veinal and 1 discal setae; posteromarginal and anteromarginal fringe cilia straight ( Fig. 9 ). Hind tibiae with 2 stout spines at apex; hind tarsi with 2 spines located one behind the other laterally. Abdominal tergites 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 3–5 discal setae on lateral microtrichial fields of III–VII ( Fig. 11 ); tergite VIII with microtrichia anteromedially, having complete posteromarginal comb; tergite IX with microtrichia posteromedially but without campaniform sensilla; tergite X with microtrichia posteromedially ( Fig. 8 ); sternites II–VII fully covered by rows of microtrichia, posterior margin with complete comb of 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; with paired trivial flange projection ( Fig. 12 ).

Measurements (holotype female in microns). Body length 910. Head, length 70; width across eyes 130; ocellar setae III 13; postocular setae I 18; postocular setae II 13. Pronotum, length 90; width 155; posteromarginal setae I 18; posteromarginal setae II 23. Fore wing length 550. Antennal segments III–VIII length 45, 35, 33, 35, 5, 8.

Male macroptera. Similar in colour and sculpture to female except body smaller ( Fig. 2 ); fore wing first vein with 6–8 basal setae, 3–4 setae on distal half; second vein with 0–1 seta; abdominal tergites III─VII median marking faded; tergite IX with a pair of dark, incurved drepanae ( Fig. 10 ); with pale antecostal ridges and without pore plate on abdominal sternites.

Measurements (paratype male in microns). Body length 750. Head, length 55; width across eyes 115; ocellar setae III 15; postocular setae I 15; postocular setae II 13. Pronotum, length 78; width 138; posteromarginal setae I 15; posteromarginal setae II 25. Fore wing length 450. Antennal segments III–VIII length 35, 30, 28, 33, 5, 8.

Material studied. Holotype female, INDIA, Karnataka, Doddaballapura, Ghati , collected on leaves of Senegalia pennata ( Fabaceae ) ( Fig. 13 ), 04.viii.2023 (Amarendra B.) ( ICAR / NBAIR / THYS /04082023) . Paratypes: 22 females and 6 males with same data as holotype except one paratype female with one additional postocular seta displaced behind the first row and three paratype females having an additional fore vein seta displaced below on the apical half of fore wing . Holotype and paratypes deposited in the National Insect Museum, National Bureau of Agricultural Insect Resources ( ICAR-NBAIR), Bengaluru, India.

Etymology: The name donumdei is derived from Latin words donum (gift) and dei (God), and means “gift of God”.

Molecular characterization: A partial mtCOI gene of S. donumdei was sequenced which showed 86.95 per cent identity with the GenBank sequence of S. dorsalis . The annotated gene sequence of the species was deposited in the National Centre for Biotechnology Information (NCBI) database, accession number OR483938.

Comments: This new species is compared with the other five members of Scirtothrips that share the character states of the sternites fully covered with microtrichia, and the sternal posterior margins with a comb of microtrichia. It can be distinguished from S. aurantii by having ocellar setae III close to the fore ocellus on tangent between fore and hind ocelli, straight posteromarginal fringe cilia, microtrichia on tergite IX and males not having a comb of stout dark setae on the posterior margin of the hind femora. From S. lantanae Ng, Mound & Azidah, 2014 , it differs in body and wing colouration, position of ocellar setae III, length of posteromarginal setae on pronotum, median setae position on metathorax, pairs of discal setae in microtrichial field of abdominal tergites II–IV. Moreover, males of the new species have drepanae on abdominal tergite IX.

Scirtothrips temengorensis Ng & Mound, 2016 can be distinguished from the new species by the males having a pair of broad, elongate and striate setae on tergite X, and tergite IX not having drepanae. The new species can be distinguished from S. convexum Ng et al. 2023 by having pale body, ocellar setae III close to fore ocellus on tangent between fore and hind ocelli, posteromarginal setae S2 setae 1.3 times as long as S1, metanotal median setae pair near or at the anterior margin, fore wing second vein with 2–3 setae, clavus with 3–4 marginal setae and abdominal tergite VIII with rows of microtrichia anteromedially. Finally, S. longifascies Ng et al. 2023 can be distinguished from the new species by having abdominal tergites and sternites pale including antecostal ridges, long pointed mouth cone, ocellar setae III on tangent between anterior margins of hind ocelli, pronotum as wide as long with stippled posterior margin, four pairs of subequal posteromarginal setae, second vein of fore wing with 1 seta and abdominal sternites III–VI with 12 posteromarginal setae.

Figures

FIGURE 13. Senegalia pennata, host plant of Scirtothrips donumdei sp. n.

FIGURES 1–6. Scirtothrips donumdei sp. n. (1) Female; (2) Male; (3) Meso and metanotum;(4) Antenna; (5) Head, dorsal; (6) Meso and metasternum.

FIGURES 7–12. Scirtothrips donumdei sp. n. (7) Pronotum; (8) Female abdominal tergites VIII–X; (9) Fore wing; (10) Male abdominal tergites IX–X; (11) Female abdominal tergites III–VII; (12) Female abdominal sternites II–VII.