Xyphandrothrips formosae, Okajima & Masumoto, 2025

Xyphandrothrips formosae sp. nov.

( Figs 352 View FIGURES 349–358 , 382–389 View FIGURES 382–389 )

Female (macroptera). Distended body length: 1.5–1.6mm. Body dark brown ( Fig. 352 View FIGURES 349–358 ). Fore femora dark brown, mid and hind femora brown; tibiae pale brown, mid and hind tibiae with apical one-third yellowish; tarsi yellow. Antennal segments I–II and IV–VIII brown to dark brown, but segment II somewhat paler antero-externally, segment IV with extreme base yellowish, with apical one-third scarcely paler; segment III yellow, scarcely tinged with pale brown. Fore wing very weakly shaded with pale brown, but basal one-third pale. Major body setae pale. Head ( Fig. 382 View FIGURES 382–389 ) a little longer than wide, about 1.2 times as long as wide, 1.18 times in holotype; dorsal surface almost smooth.

Cheeks weakly rounded, gradually narrowed to base, very weakly serrated. Eyes a little shorter than 0.3 times as long as head. Ocelli relatively small; posterior pair separated from eyes, about 30µm apart from each other in holotype. Postocular setae shorter than eyes, weakly expanded; 94µm apart from each other, 6–7µm apart from eyes in holotype. Antennae ( Fig. 389 View FIGURES 382–389 ) about 1.7 times as long as head, 1.68 times in holotype; segment VIII short and conical, closely joined to segment VII, but basal width often somewhat narrower than apical width of VII ( Figs 387 & 388 View FIGURES 382–389 ); segments III almost symmetrical, truncated at apex, shorter than IV, almost as long as VII; segment IV the largest; segments III and IV with two (1+1) and four (2+2 +1) sense cones respectively. Maxillary stylets retracted to eyes, sub-parallel at middle, their distance about one-fifth of head width, or a little narrower; maxillary bridge weak. Pronotum ( Fig. 382 View FIGURES 382–389 ) more than 0.6 times as long as head, 0.64 times in holotype, about 1.7 times as wide as long, 1.71 times in holotype; almost smooth, median apodeme very weak; five pairs of prothoracic setae weakly expanded; am and aa subequal in length, ml and pa subequal, epim a little longer than pa and almost as long as postocular setae. Prospinasternum ( Fig. 383 View FIGURES 382–389 ) largely developed, irregularly fan-shaped, about 35µm wide in holotype; mesopresternum narrowly boat-shaped or separated into lateral triangle plates. Mesonotal lateral setae developed, weakly expanded. Metanotum ( Fig. 384 View FIGURES 382–389 ) weakly sculptured with reticulation; median pair of setae pointed, about 20µm, distance between both median setae wider than distance between each seta and anterior margin of metanotum, 45µm apart from each other, 28–30µm apart from anterior margin in holotype. Fore tarsal tooth long and slender ( Fig. 386 View FIGURES 382–389 ). Fore wing with 2–5 duplicated cilia, 3–5 in holotype; sub-basal setae S1 and S2 expanded, S3 finely pointed and the longest. Pelta ( Fig. 385 View FIGURES 382–389 ) trapezoid with irregular lateral margins, 1.57 times as wide as long in holotype. Tergites III – VIII S2 setae: III expanded, IV – VI and VIII bluntly pointed, VII finely pointed. Tergite IX S1 setae bluntly pointed or almost pointed, almost as long as tube, S2 sharply pointed, a little shorter than S1; intermediate setae about half of Sl. Tube much shorter than 0.5 times as long as head, 0.45 times in holotype, about 1.6 times as long as wide; terminal setae about 1.3 times as long as tube .

Measurements (holotype female in µm). Body length about 1500 (distended). Head length 173, from anterior margin of eyes 163, width across eyes 130, maximum width across cheeks 146, minimum width across base 123; eyes length 47; diameter of posterior ocelli 8–11; postocular setae about 30. Maxillary bridge width 28. Antenna total length 290, segments III–VIII length (width) as follows: 37 (26), 41 (28), 40 (26), 37 (23), 37 (22), 20 (11). Pronotum length 110, width 188. Setae on prothorax: am 20, aa?20, ml 28–30, pa 32, epim 35. Fore wing length 600. Sub-basal wing setae: S1 25 –28, S2 28 –30, S3 37. Pelta length 53, width 83. Tergite IX setae: S1 80, S2 72–75. Tube length 78, maximum width 48; terminal setae 100.

Male. Unknown.

Type material. Holotype: macropterous female, Taiwan, Taoyuan Hsien, Mt. Lala-shan , on dead leaves and branches, 19.viii.1993, TN & SO . Paratypes: Taiwan, 1 female, Nantou Hsien, foot of Mt. Nankao, nr. Wanta , on dead branches, 4.iv.1984, SO ; 1 female, Taipei Hsien, Mt. Tatung shan, on dead branches, 4.iv.1984, SO .

Comments. This species is very similar to X. conjunctus sp. nov. described above also from Taiwan. However, it is distinct in the following features (in parentheses are the features of conjunctus ): antennal segments VII and VIII not forming a single segment (closely joined and forming a single segment); antennal segment II largely brown (brownish yellow); dorsal surface of head almost smooth (sculptured with transverse striae especially between postocular setae); sub-basal setae S3 finely pointed (expanded); posteromarginal setae S1 on the abdominal tergite IX a little longer than S2 (much shorter than S2).