Terthrothrips levigatus, Tong, 2017

Tong, Xiaoli, 2017, Two new species and a new record of the fungivorous genus Terthrothrips from China (Thysanoptera: Phlaeothripidae), Zootaxa 4323 (4), pp. 561-571 : 562-565

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).

Figures

FIGURES 1 – 4. Terthrothrips levigatus sp. n. (1) dorsal view of head; (2) pronotum (arrows indicate the anteromarginal setae); (3) ventral view of prothorax; (4) dorsal view of pterothorax.

FIGURES 5 – 9. Terthrothrips levigatus sp. n. (5) abdominal sternites VI – IX of female (6) abdominal sternites VI – IX of male; (7) pelta; (8) tube; (9) antenna.

FIGURES 21 – 24. Terthrothrips species. (21) T. levigatus sp. n. (female), (22) T. levigatus sp. n. (male); (23) T. trigonius sp. n. (female), (24) T. trigonius sp. n. (male).