Hydatothrips initium, Rachana & Amarendra & Gracy, 2022

Rachana, R. R., Amarendra, B. & Gracy, R. Gandhi, 2022, The Sericothripinae genus Hydatothrips (Thysanoptera, Thripidae) in India with description of a new species, Zootaxa 5169 (2), pp. 177-182 : 178-181

Hydatothrips initium sp.n.

Female macroptera. Body bicoloured ( Fig. 5 ); head and pterothorax brown; pronotum yellow with blotch shaded; metanotum pale at posterior third ( Fig. 7 ); abdominal segment I yellowish brown with antecostal ridge interrupted medially, II–III brown, VII–IX brown, X yellow with brown infusion; antecostal ridges on tergites II–VII complete and dark brown; antennal segments I–III yellow, IV yellow with apical brown infusion, V–VIII brown. Fore wing brown with a pale sub-basal area, basal ¾ of clavus brown ( Fig. 10 ); all femora, tibiae and tarsi brown. Antennae 8-segmented ( Fig. 12 ). Head wider than long, with sculpture lines within ocellar triangle, with internal markings; occipital apodeme touching posterior margin of eyes; ocellar setae III placed inside ocellar triangle; post-occipital area with transverse striations; three pairs of postocular setae along posterior inner margin of eyes, all subequal and subequal to ocellar setae III ( Fig. 8 ). Pronotum transversely reticulate with internal markings; blotch well defined, transversely reticulate with internal markings, concave at anterior margin, posterior margin merged with pronotal posterior margin; short posteroangular setae; 3 pairs of posteromarginal setae ( Fig. 9 ). Mesonotum transversely striate, with internal markings, median pair of setae ahead of sub-median pair well anterior to posterior margin ( Fig. 7 ). Metanotum sculptured transversely anteromedially, longitudinally at each side, irregularly reticulate at middle, with internal markings; median setae a little behind anterior margin ( Fig. 7 ). Fore wing first vein with continuous row of setae, second vein without setae ( Fig. 10 ). Abdominal tergites I–VI medially without marginal microtrichia; VII–VIII with complete row of marginal microtrichia; tergites I–II with discal microtrichia laterally, III–V with discal microtrichia medially and laterally ( Figs 14, 18 & 19 ), VI–VIII fully covered with discal mirotrichia; IX with no discal microtrichia; X with discal microtrichia posteriorly ( Fig. 13 ); tergites III–VI with setae S3 positioned well ahead of posterior margin, with 2–3 setae lateral to S3 ( Figs 14, 15, 18 & 19 ); tergite IX with 2 pairs of mid-dorsal setae ( Fig. 13 ). Abdominal sternites without discal setae; III–VI completely covered with discal microtrichia, posterior margin with complete comb of microtrichia interrupted only at setal bases, posteromarginal setae at sternite VII arising in front of posterior margin.

Measurements (holotype female in microns). Body length 920. Head, length 90; width across eyes 140; ocellar setae III 10; postocular setae I 10. Pronotum, length 95; width 175; pronotal blotch length (50 median, 70 lateral); width 140. Metanotum median setae length 25. Fore wing length 600. Antennal segments III–VIII length 50, 45, 35, 45, 10, 10.

Male macroptera. Similar to female, but smaller in size ( Fig. 6 ); sternites VI–VII with elongated transverse pore plate ( Fig. 16 ).

Measurements (paratype male in microns). Body length 660. Head, length 60; width across eyes 135; ocellar setae III 10; postocular setae I 10. Pronotum, length 80; width 160; pronotal blotch length (45 median, 60 lateral); width 125. Metanotum median setae length 25. Fore wing length 550. Antennal segments III–VIII length 45, 40, 35, 40, 5, 10.

Material studied. Holotype female, INDIA, Tamil Nadu, Dindigal, Thadiyankudisai , collected in yellow pan traps, 27.i.2017 (Gandhi Gracy R.) ( ICAR / NBAIR / THYS/27012017 ) . Paratypes: 1 female ( ICAR / NBAIR / THYS/270120171 ) and 2 males ( ICAR / NBAIR / THYS/270120172 ; ICAR / NBAIR / THYS/270120173 ) with same data as holotype . Holotype and paratypes deposited in the National Insect Museum , National Bureau of Agricultural Insect Resources ( ICAR-NBAIR), Bengaluru, India .

Etymology: Department of Science and Technology-Science and Engineering Research Board (DST-SERB) has funded a project on “Taxonomy and diversity of terebrantian thrips ( Thysanoptera : Terebrantia) from south India with special reference to Western Ghats” to the first author in 2021. The species name initium , meaning “beginning’’, is in reference to that commencement of studies on thrips fauna of south India.

Comments: None of the species described in the genus Hydatothrips (except H. boerhaaviae and H. bahaensis ) has the following combination of characters: setae S3 on abdominal tergites IV–VI arising far from posterior margin; head, pronotum, mesonotum and metanotum with internal markings; sternites II–VII completely covered with discal microtrichia, posterior margin with complete comb of microtrichia interrupted at setal bases; male with transverse pore plate on sternites VI–VII. This species differs from H. boerhaaviae by having: ocellar setae III positioned inside ocellar triangle (ocellar setae III arise at tangent between outer margins of fore and hind ocelli in H. boerhaaviae ); abdominal tergites IV–VI with 2–3 setae lateral to S3 (abdominal tergites IV–VI with 6–9 setae lateral to S 3 in H. boerhaaviae ). Hydatothrips bahaensis , described from Saudi Arabia can be distinguished from the new species by having reddish brown body, longitudinally reticulate metanotum, median setae on metanotum at anterior margin and 6–8 setae lateral to S3 on abdominal tergites IV–VI.

Figures

FIGURES 5–12. Hydatothrips initium sp.n. (5) Female; (6) Male; (7) Meso and metanotum; (8) Head, dorsal; (9) Pronotum; (10) Fore wing; (11) Metasternum; (12) Antenna.

FIGURES 13–19. Hydatothrips initium sp.n. (13) Female abdominal tergites IX–X; (14) Abdominal tergite III; (15) Abdominal tergite VI; (16) Pore plate on male abdominal sternites VI–VII; (17) Abdominal tergite VIII; (18) Abdominal tergite V; (19) Abdominal tergite IV.