Phlaeothrips annamensis sp. n., 2024

Okajima, Shûji & Masumoto, Masami, 2024, The genus Hoplandrothrips and its relatives (Thysanoptera: Phlaeothripidae) from Southeast Asia and Taiwan, Zootaxa 5489 (1), pp. 22-91 : 56-57

Phlaeothrips annamensis sp. n.

( Figs 52–53 , 271–278 )

Large male (macroptera). Distended body length: 6.5mm. Dorsal surface strongly sculptured with fine reticulation (except for head). Body dark brown. Antennal segments I and II dark brown, segment II with paler apex; segment III – VIII brown, outer side of segment III somewhat yellowish. Femora dark brown; fore tibiae brown, yellowish interiorly and apically; mid and hind tibiae dark brown, with yellowish apices. Fore wings weakly shaded with brown, each with a dark streak. Prominent setae yellowish, but S2 setae on tergite IX darker. Head ( Figs 271 & 272 ) about 1.8 times as long as wide, dorsal surface weakly sculptured with transverse rough striae or warts, but weakly sculptured with fine transverse reticles, ocellar region sculptured with very fine longitudinal reticles. Cheeks very weakly rounded, almost parallel, each with 7–8 short setae arising on small warts or tubercles, some of which are stout, spine-shaped, 40–50μm long in holotype. Postocular setae situated near cheeks, behind the middle of head, blunt at apex, much shorter than eye, 160–165μm apart from eyes, 305μm apart from each other in holotype; ocellar setae minute. Eyes well-developed, about 1/3 as long as head, but smaller on ventral surface. Posterior ocelli close to eyes, anterior ocellus probably looked forward (it is poorly visible in the type specimens). Antenna ( Fig. 273 ) 8-segmented, segment VIII slender, constricted basally, pedicellate; segment I a little longer than segment II; segments III and IV subequal in length; segments III – VI with short apical neck. Mouth cone short and rather pointed; maxillary stylets retracted to middle of head, close together; maxillary bridge absent. Pronotum well-developed, wider than long, 0.66 times as long as head, 1.49 times as wide as long in holotype; ml, pa and epim developed, but short; epimeron with a stout accessory seta situated before epim. Prosternal ferna ( Fig. 276 ) distinct; mesopresternum divided into three plates. Mesonotal lateral setae developed, but short. Metanotum ( Figs 274 & 275 ) medially strongly swollen into a longitudinal oval shape in large male, of which the dorsum is not sculptured, almost smooth, median pair of setae short. Fore coxa with a series of stout setae on postero-lateral margin. Fore femur largely developed, without long setae, with a series of minute but spine-shaped setae on inner margin; fore tibia with two small tubercles on inner apex; fore tarsal tooth robust, wide-based. Fore wing parallel-sided, each with more than 60 duplicated cilia; sub-basal setae ( Fig. 277 ) dilated, S3 much longer than S2. Pelta ( Fig. 274 ) trapezoidal, distinctly sculptured, with a pair of campaniform sensilla. Abdominal tergites II – VI each with two pairs of sigmoid wing-retaining setae, anterior pair each with some sigmoid accessory wing-retaining setae on outside; sternites II – VII each with a pair of antero-lateral depressions; intermediate abdominal sternites each with two transverse rows of minute discal setae; sternite VIII with narrow and arched pore plate. Tergite IX S1 setae a little longer than 1/2 of tube length; internal setae short. Tube ( Fig. 278 ) about 0.7 times as long as head, terminal setae shorter than tube.

Measurements (holotype large male in μm). Body length about 6500 (distended). Head length 700, from anterior margin of eyes 680, width across eyes 370, maximum width across cheeks 390; eyes length 236, width 135; diameter of posterior ocelli 40; postocular setae?130–140. Antenna total length 1180, segments I–VIII length (width) as follows: 135 (80), 130 (64), 200 (94), 200 (83), 190 (72), 137 (50), 105 (40), 95 (25). Pronotum length 460, width 685. Setae on prothorax: ml about 50, pa 70–75, epim 135–140, cox about 100. Fore wing length?2750. Sub-basal wing setae: S1 80, S2 80, S3 110. Tergite IX setae: S1 260–270, S2 100. Tube length 485, basal width 185, apical width 80; terminal setae 270–280.

Small male (macroptera). Distended body length: 5.5mm. Head about 1.6 times as long as wide, eyes 0.37 times as long as head; cheeks each with 5–7 short setae. Pronotum 0.54 times as long as head, 1.74 times as wide as long. Fore tibia without apical tubercles. Metanotum weakly swollen medially into an inverted triangle, with longitudinal fine reticulation. Fore wing with about 50 duplicated cilia. Tube 0.75 times as long as head.

Measurements (paratype small male in μm). Body length about 5510 (distended). Head length 560, from anterior margin of eyes 540, width across eyes 330, maximum width across cheeks 345; eye length 210, with 120. Pronotum length 305, width 530. Tube length 420, basal width 160, apical width 75.

Type series, Holotype: large macropterous male, Vietnam, Tam Dao , 23.v.1993, K. Matsumoto . Paratype: Vietnam, 1 small male, collected with holotype .

Remarks. P. annamensis shows distinct allometry in male and is peculiar in having the body very large with the head elongate, and a sternal pore plate in male, but other features are indistinguishable from the type-species. However, antennal segments III–VI are somewhat similar to those of Acanthothrips in having a short apical neck. The tentorial cover of the holotype large male is distinctly protruded, but this may be due to the allometric growth.

Figures

FIGURES 43–55. Hoplandrothrips and Phlaeothrips species. H. samirseni comb. n. 43–44: (43) female; (44) large male. H. sapae sp. n. 45–47: (45) female; (46) small male; (47) large male. H. sulawesi sp. n. 48–50: (48) female; (49) large male; (50) small male. H. thailandicus sp. n.: (51) female. P. annamensis sp. n. 52–53: (52) small male; (53) large male. P. tonkinensis sp. n. 54–55: (54) female; (55) male.

FIGURES 271–278. Phlaeothrips annamensis sp. n., male. (271) Head, prothorax and fore leg, large male; (272) head, prothorax and fore leg, small male; (273) antenna; (274) metanotum and pelta, large male; (275) metanotum, small male; (276) prosternum and mesopresternum; (277) sub-basal wing setae; (278) tube.