Xyphandrothrips megacephalus, Okajima & Masumoto, 2025

Xyphandrothrips megacephalus sp. nov.

( Figs 354–355 View FIGURES 349–358 , 400–407 View FIGURES 400–407 )

Female (macroptera). Distended body length: about 1.8mm. Body brown to dark brown (holotype female is somewhat paler than paratype female) ( Fig. 354 View FIGURES 349–358 ). All femora entirely brown to dark brown, concolorous with head; all tibiae brown, mid and hind tibiae with apices scarcely paler; tarsi yellow. Antennal segments I– II and IV – VIII brown to dark brown, segment IV with base yellowish; segment III largely yellow, with distal half scarcely shaded with brown. Fore wing pale, scarcely shaded with brown at middle. Major body setae pale. Head ( Fig. 400 View FIGURES 400–407 ) much longer than wide, about 1.3 times as long as wide, 1.31 times in holotype, widest across cheeks; dorsal surface almost smooth at middle, sculptured with transverse striae laterally. Cheeks weakly rounded, weakly serrated. Eyes relatively small, about one-fifth of head length. Posterior ocelli slightly separated from eyes, 44µm apart from each other in holotype. Postocular setae a little longer than eyes, pointed; 103µm apart from each other, about 12µm apart from eyes in holotype. Antennae ( Fig. 407 View FIGURES 400–407 ) 1.65 times as long as head; segment VIII conical, narrowly but closely joined to segment VII, about three-fifths of VII in length; segments III and IV subequal in length, longer than VII; segments III and IV with two (1+1) and four (2+2 +1) sense cones respectively. Maxillary stylets retracted to eyes, close together, sub-parallel, 17–18µm apart from each other; maxillary bridge invisible even if using the phase contrast microscope. Pronotum ( Fig. 400 View FIGURES 400–407 ) about 0.6 times as long as head, 0.63 times in holotype, 1.63 times as wide as long in holotype; almost smooth, but sculptured at near posterior margin; four pairs of pronotal setae pointed or blunt, am, aa and pa pointed, ml blunt; epim blunt or very weakly expanded. Prospinasternum ( Fig. 402 View FIGURES 400–407 ) irregularly fan-shaped, about 35µm wide in holotype; mesopresternum narrowly boat-shaped. Mesonotal lateral setae well developed, pointed, 20–23µm long. Metanotum ( Fig. 403 View FIGURES 400–407 ) weakly sculptured with polygonal reticulation; median pair of setae pointed, longer than 20µm, distance between both median setae much wider than distance between that seta and anterior margin of metanotum, 58µm apart from each other, 28–33µm apart from anterior margin in holotype. Fore tarsal tooth long ( Fig. 404 View FIGURES 400–407 ). Fore wing with 2–4 duplicated cilia; sub-basal setae S1 and S2 expanded, S3 pointed; S3 the longest. Pelta trapezoid with irregular lateral margins, 1.53 times as wide as long in holotype. Tergites III – VIII S1 and S2 setae sharply pointed. Tergite IX S1 and S2 setae pointed, subequal in length, shorter than tube; intermediate setae shorter than half of Sl. Tube shorter than 0.5 times as long as head, 0.46 times in holotype, about 1.8 times as long as wide; terminal setae about 1.2 times as long as tube .

Measurements (holotype female in µm). Body length about 1800 (distended). Head length 207, from anterior margin of eyes 197, width across eyes 136, maximum width across cheeks 158, minimum width across base 130; eyes length 42; diameter of posterior ocelli 8–13; postocular setae 46. Antenna total length 340, segments III–VIII length (width) as follows: 47 (27), 47 (29), 43 (27), 43 (23), 40 (23), 23 (12). Pronotum length 130, width 212. Setae on prothorax: am 23–25, aa?25, ml 40, pa 40, epim?40. Fore wing length 630. Sub-basal wing setae: S1 30, S2 30 –32, S3 45 –47. Pelta length 59, width 90. Tergite IX setae: S1 83–85, S2 84–85. Tube length 95, maximum width 53; terminal setae 110–115.

Male (macroptera). Distended body length: 1.5–1.6mm. Very similar to macropterous female in color and structure, but show allometric growth. Large male: prothorax and fore legs enlarged; fore trochanter with a triangular inner tubercle ( Fig. 405 View FIGURES 400–407 ); pronotal am setae reduced. Tip of pseudovirga rounded ( Fig. 406 View FIGURES 400–407 ), about 15µm wide.

Measurements (paratype male in µm). Body length about 1600 (distended). Head length 196, from anterior margin of eyes 184, width across eyes 130, maximum width across cheeks 139, minimum width across base 112; eyes length 46; diameter of posterior ocelli 810; postocular setae 40. Antenna total length 335, segments III–VIII length as follows: 45, 47, 45, 40, 41, 24. Pronotum length 135, width 200. Setae on prothorax: am 10–15, aa 25, ml 35, pa 44, epim 40. Fore wing length 640. Sub-basal wing setae: S1 27 –28, S2 33 –35, S3 38 –40. Pelta length 54, width 87. Tergite IX setae: S1 80, S2 35. Tube length 89, maximum width 48; terminal setae 116.

Type material. Holotype: macropterous female, Taiwan, Nantou Hsien, Meifeng , on dead leaves and branches, 1.ix.1994, TN & SO . Paratypes: Taiwan, 1 female and 1 male, collected together with holotype ; 1 male, same locality as holotype , alt. about 2000m, habitat uncertain, 28.iii.1984, SO.

Comments. This species is described from the mountainous area of central Taiwan based on two females and two males. It is peculiar in the genus in having the following features: eyes small, about one-fifth of head length; postocular setae pointed and a little longer than eyes; maxillary stylets close together, much narrower than one-fifth of the head width; four pairs of pronotal major setae pointed or blunt .