Terthrothrips levigatus Tong 2017, sp. n.

Terthrothrips levigatus sp. n.

(Figs. 1–9, 21, 22)

Female. Macroptera (Fig. 21). Body and legs entirely brown except tarsi yellow; antennal segments I–II brown, III yellowish brown, IV–VIII light brown; wings weakly shaded light brown except pale medially; major setae weakly shaded.

Head (Fig. 1) approximately 1.2 times as long as wide; dorsal surface sculptured laterally and posteriorly, with polygonal reticulation between eyes; cheeks nearly straight, slightly constricted behind eyes. Eyes approximately one-third of head length, equally developed ventrally and dorsally; ocelli well developed; postocellar setae pointed and as long as hind ocellus; postocular setae stout, longer than eyes with expanded apex. Antennae (Fig. 9) approximately 2 times as long as head length; segments III and IV each with three (2+1) sense cones; segment VI longer than segment VIII; terminal setae slightly longer than segment VIII. Maxillary stylets wide apart, retracted slightly into head capsule. Mouth-cone short and rounded.

Pronotum (Fig. 2) smooth, transverse with anterior margin concave, notopleural sutures complete; pronotal aa well developed, as long as ml, epim and pa, expanded apically, pronotal am fine, as long as postocellar setae, pointed apically; basantra present, but membranous, paired ferna well-developed. Mesonotum with pair of long lateral setae, slightly shorter than pronotal aa and expanded at apex; mesopresternum eroded medially, divided into two triangular lateral plates (Fig. 3), with prospinasternum developed. Metanotum (Fig. 4) smooth medially with polygonal reticulation laterally, median pair of setae long and pointed; metathoracic sternopleural sutures absent. Fore tibiae without tubercles on inner margin; fore tarsal tooth present. Fore wing almost parallel-sided without duplicated cilia; three pairs of sub-basal setae present and expanded at apex.

Pelta (Fig. 7) long hat-shaped with flat anterior margin, nearly 2 times as long as apical width, with slender lateral lobes and dorsal surface sculptured with irregular reticulation, and a pair of campaniform sensilla present; abdominal tergites II–VII each with 2 pairs of sigmoid wing retaining setae, anterior pair weaker than posterior pair; tergite VIII without wing-retaining setae; sternites II–VIII with transverse row of 6–18 discal setae medially, each with 2 pairs of equally developed long and stout setae arising in front of posterior margin, but VIII with an additional pair of short and fine setae situated at posterior margin (Fig. 5); tergite IX setae S1 as long as S2, both shorter than tube and blunt or expanded at apex, intermediate setae (iS) longer than half of S1 (Fig. 8); tube almost 0.7 times as long as head; anal setae shorter than tube.

Measurements (holotype female in microns). Distended body length 1725. Head length 220, width 185; eyes length 70; postocular setae length 75; diameter of anterior (posterior) ocelli 19; postocellar setae length 16. Antennae length 440, segments I–VIII length (width) as follows: 37(41); 53(29); 74(28); 66(28); 66(24); 60(21); 42(21); 41(13); terminal setae length 60. Pronotum median length 125, width across median part 290; length of major setae: am 15, aa 60, ml 75, pa 80, epim 72. Fore wing length 700, subbasal setae S1–S3 length: 60, 65, 65. Metanotum median setae 33. Pelta length 84, width with lateral lobes 125, width at apex 43; abdominal tergite IX S1 setae length 108, intermediate setae (iS) length 90, S2 setae length 108. Tube length 135, width at base 85, at apex 43; anal setae length 55.

Male. Macroptera (Fig. 22). Similar in colour and structure to female, but smaller. Abdominal sternites II–VIII with 4–12 discal setae medially; sternite VIII with only 2 pairs of posteromarginal setae arising in front of posterior margin; sternite IX with a pair of prominent setae medially (Fig. 6); tergite IX setae S2 acute and approximately one-third as long as S1.

Measurements (paratype male in microns). Distended body length 1300. Head length 220, width 160; eyes length 60; postocular setae length 60; diameter of anterior (posterior) ocelli 18; postocellar setae length 12. Antennae length 420, segments I–VIII length (width) as follows: 37(35); 42(29); 76(25); 65(26); 68(23); 56(20); 38(19); 38(13); terminal setae length 40. Pronotum median length 110, width across median part 260; length of major setae: am 14, aa 60, ml 54, pa 55, epim 60. Fore wing length 640, subbasal setae S1–S3 length: 50, 60, 50. Metanotum median setae 25. Pelta length 70, width at base 90, width at apex 37; abdominal tergite IX S1 setae length 110, intermediate setae (iS) length 80, S2 setae length 38. Tube length 110, width at base 75, at apex 30; anal setae length 55.

Material examined. Holotype. Female macroptera, CHINA, Guangdong: Conghua, Guangzhou City, Shimen National Forest Park (23°32'N, 113°32'E), 19.ix.2004, Jun Wang.

Paratypes. 1 female and 1 male, collected with holotype. CHINA, Guangdong: 1 female and 1 male, Zhaoqing City, Dinghushan National Nature Reserve (23°10'N, 112°32'E), 14.vi.1987, Xiaoli Tong.

Etymology. The Latin word levigatus means smooth, referring to the metanotum without sculpture medially.

Distribution. China (Guangdong).

Remarks. This new species resembles T. parvus in sharing 4 pairs of well-developed setae on the pronotum, and fore tibiae without tubercles on inner margin, but it can be readily distinguished from the latter by the following diagnostic characters: (1) Metanotum smooth medially (metanotum sculptured with polygonal reticulation in T. parvus); (2) pelta long hat-shaped with flat anterior margin, nearly 2 times as long as apical width, with distinctly reticulate sculpture (pelta irregularly hat-shaped and surface weakly reticulate in T. parvus); (3) female sternite VIII with pair of setae submedially in front of posterior margin, which are equally developed as those on sternites II–VII (paired setae on VIII in parvus somewhat leaf-like, much stouter than those on sternites II–VII).