Holarthrothrips indicus Bhatti & Ananthakrishnan, 1978

Feng, Qingjing & Tong, Xiaoli, 2021, First record of an extant species of the family Stenurothripidae from China (Insecta: Thysanoptera), Zootaxa 5040 (3), pp. 448-450 : 448-449

Holarthrothrips indicus Bhatti & Ananthakrishnan (Figs 1–10)

Holarthrothrips indicus Bhatti & Ananthakrishnan, 1978: 229 .

Female macroptera. Body dark brown (Fig. 1). Antennal segments I and II pale brown, III and IV yellow, V–IX dark brown; fore wing pale, without any shadings ( Fig. 7 ); legs yellow except femora slightly shaded along outer margin. Head (Fig. 3) slightly wider than long, sculptured with transverse anastomosing striae dorsally; three pairs of ocellar setae subequal in length, pair III arising within ocellar triangle; postocular setae apparently biserial, six pairs of short setae in oblique row and two pairs of longer setae near middle of dorsum. Antennae 9-segmented ( Fig. 5 ), all segments well separated, III & IV each with a conical sense cone with wider base ( Fig. 6 ); segment I without paired dorso-apical setae, II–IX with transverse rows of microtrichia, IX approximately five times longer than wide. Maxillary palps 3-segmented. Cephalic tentorium full developed, tentorial bridge complete, connected with anterior tentorial arms and posterior tentorial arms, the anterior arms slender, but the bases clearly visible. Pronotum wider than long, with transverse anastomosing striae; two pairs of anteromarginal setae distinctly longer than discal setae; one pair of long posteroangular setae and 7 pairs of posteromarginal setae present. Mesonotum (Fig. 4) with transverse lines of sculpture between and around campaniform sensilla (CPS) near anterior margin, median pair of setae arising well in front of posterior margin. Metascutum with concentric rings of sculpture bearing microtrichia (Fig. 4), one pair of setae close to posterior margin and one pair of longer setae near anterior margin; CPS present posteromedially. Fore wing ( Fig. 7 ) first vein with 17–20 setae, arranged in a nearly continuous series or with short irregular intervals; second vein with continuous series of 15–18 setae; clavus with 8 veinal setae and one discal seta near base; posteromarginal fringe cilia straight. Prosternal ferna weakly connected at middle; basantra membranous, without setae; prospinasternum transverse. Mesosternum with sternopleural sutures complete (Fig. 2) and with endofurcal spinula. Metasternal sternopleural sutures absent (Fig. 2), endofurca without spinula. Tarsi 2-segmented, fore tarsus with a small recurved claw. Abdominal tergites with transverse lines of sculpture; tergite I with posterior pair of CPS ( Fig. 8 ), II–IX with median pair of CPS, X with anterior pair of CPS; tergites II–VII with paired longitudinal weakly chitinized fissures sublaterally ( Fig. 10 ); II–VIII lateral thirds with numerous ciliate microtrichia on sculpture lines; VII–VIII with complete comb of long microtrichia on posterior margin ( Fig. 10 ), but no comb medially on remaining tergites; X without median split. Sternites II–III each with 2 discal setae, IV–VII with 4–8 discal setae; sternites II–VI with complete posteromarginal comb of fine microtrichia, VII absent the comb medially; posterior margins on sternites III–VII with 4 pairs of setae, II with 2 pairs, S1 setae on VII at posterior margin ( Fig. 9 ).

Material examined. China, Guangdong Province, Guangzhou City, the campus of South China Agricultural University. 4 females collected from Cordyline fruticosa [ Liliaceae ], 7 females from Osmanthus fragrans [ Oleaceae ], one female from Ligustrum quihoui [ Oleaceae ], 27.xii.2020 (Qingjing Feng).

Remarks. In colour and structure H. indicus is very similar to H. josephi known from Iraq and Iran ( Minaei 2013). However, josephi lacks CPS on abdominal tergite I, and tergites II–VI have the posteromarginal comb of fine microtrichia complete medially ( Bhatti 1986). H. indicus is also similar to H. tenuicornis in general appearance, but it can be distinguished easily by the unshaded fore wings, by the absence of oblique sternopleural sutures on the metasternum, and the presence of discal setae on the abdominal sternites. Although, as indicated above, the species of Holarthrothrips are considered to live in the inflorescences of Phoenix spp. , we collected H. indicus only from three plants in unrelated families. These collections were made in the winter, and it is possible that this thrips may disperse to various evergreen plants for overwintering in southern China.

FIGUERS 1–4. Holarthrothrips indicus : (1) Female; (2) Prosternum, meso- & metasternum; (3) Head & pronotum; (4) Meso- & metanotum

Figures

FIGURES 5–10. Holarthrothrips indicus: (5) Antenna; (6) Antennal segments II– IV; (7) Fore wing; (8) Abdominal tergite I; (9) Sternites VI & VII; (10) Tergites VI–X.