Hoplothrips hongruiae, Mound & Wang, 2020

Mound, Laurence A. & Wang, Jun, 2020, Hoplothrips species recorded from China (Thysanoptera, Phlaeothripidae), with one new species from Yunnan, Zootaxa 4758 (3), pp. 596-599 : 597-599

Hoplothrips hongruiae sp. n.

( Figs 1–5 )

Female macroptera. Body and femora brown, basal half of tube darker; tarsi and apex of tibiae yellow; antennal segment III mainly yellow, IV–V variably yellow at base; fore wings pale; major setae brown. Head ( Fig. 1 ) with transverse polygonal sculpture near base, without distinct sculpture on anterior half; cheeks widest behind eyes, narrowing to base; compound eyes about one third of head length; postocular setae capitate, much shorter than dorsal eye length; ocelli well developed; postocellar setae pointed, longer than the diameter of posterior ocelli; maxillary stylets retracted to postocular setae, 0.2–0.3 of head width apart medially, with distinct maxillary bridge. Antennae 8-segmented ( Fig. 2 ), segment III with 2 slender sense cones, IV with 4 sense cones, VIII broad at base and much shorter than VII. Pronotum with weak transverse sculpture near posterior margin; with 5 pairs of capitate major setae ( Fig. 1 ). Mesonotum with transverse reticulation on anterior half, lateral setae weakly capitate; metanotum with weak polygonal sculpture, median setae acute. Prosternum ( Fig. 5 ) with basantra weakly indicated by variable coalescence of some chitinous islets; ferna triangular almost meeting medially; mesopresternum complete; mesoeusternal anterior margin entire. Fore tarsal tooth absent. Fore wing parallel sided, with three sub-basal setae, S1 and S2 capitate, S3 longest and pointed, 4 duplicated cilia. Pelta with weak sculpture and small lateral lobes ( Fig. 4 ), campaniform sensilla located almost on margin; tergites II–VII each with two pairs of sigmoid wing-retaining setae; sternites each with 3–5 pairs of discal setae; tergite VIII median setae capitate; tergite IX setae S1 much shorter than tube and blunt, S2 pointed; anal setae shorter than tube.

Measurements (holotype female in microns). Body length 1760. Head, length 208; median width 175; dorsal eye length 70; postocular setae 40, distance between their bases 98. Pronotum, length 113; median width 230; major setae am 20, aa 20, ml 21, epim 43, pa 35. Mesonotum lateral setae 20. Metanotum median setae 25. Tergite IV median marginal setae 68; tergite VIII median setae 60; tergite IX setae S1 99, S2 90. Tube length 138; anal setae 115. Fore wing length 680; sub-basal setae S1 30, S2 37, S3 82. Antennal segments III–VIII length 62, 62, 58, 50, 45, 28.

Female microptera. Similar to macropterous female, ocelli smaller; wing-retaining setae smaller.

Measurements (in microns). Body length 1860. Head, length 223; width 170; compound eyes length 70; postocular setae 30; fore wing lobe 175; longest sense cone on antennal segment III 21.

Male macroptera. Similar to female but smaller; fore tarsal tooth present but small; tergite IX S2 setae short and stout; sternite VIII with large transverse pore plate that extends to spiracles ( Fig. 3 ); sternites without reticulate areas.

Measurements (in microns). Body length 1410. Head, length 188; width 145; postocular setae 27. Pronotum, length 95; median width 185; major setae am 15, aa 14, ml 14, epim 38, pa 16. Tergite IX setae S1 87, S2 23. Tube length 105, anal setae 100. Fore wing length 560. Antennal segments III–VIII length 53, 55, 55, 48, 42, 25.

Male microptera. Similar to macropterous male, ocelli smaller; wing-retaining setae smaller.

Measurements (in microns). Body length 1450. Head, length 200; width 150; postocular setae 31; fore wing lobe 133.

Specimens studied. Holotype female macroptera. China, Yunnan, Kunming, Western Mts, from dead leafy stems of Cryptomeria sp. [ Cupressaceae ] (LAM 6445) in Yunnan Agricultural University, Kunming.

Paratypes collected with the holotype: 8 macropterous females, 2 micropterous females, 7 macropterous males, 4 micropterous males. Paratypes are in the authors’ collections, at Canberra and at Jilin University .

Comment. This new species is named in recognition of the outstanding and critical contributions made to our knowledge of Thysanoptera in China by Prof. Zhang Hongrui. Within the genus Hoplothrips the species is unusual for its small size, but particularly in having the maxillary stylets relatively far apart with a maxillary bridge present ( Mound et al. 2020), the mesopresternum complete, and the pronotal posteroangular setae distinctly shorter than the epimeral setae. Moreover, the prosternal basantra are faintly indicated by the coalescence of some of the chitinous islets, and when the prosternal membrane is viewed slightly obliquely this can give the impression of basantra being present. However, in contrast to fungosus there is no clear sclerite present. The host association is also unusual, although no immature stages were collected. The adults were found as scattered individuals, amongst dead “leafy” stems that had fallen from the Coniferous trees. In the field this small thrips was assumed to be a species of Haplothrips , however it differs from members of the Haplothripini in the following character states: absence of basantral sclerites on the prosternum; absence of any constriction medially on the fore wing; presence of a pore plate on sternite VIII in males. However, as noted above, the male pseudovirga appears to be similar to that of Haplothrips species, although such a structure is not well-developed in all Haplothripinae including Dolichothrips species ( Mound & Okajima 2015). The current classification within the Phlaeothripinae is historically derived from the European fauna. The new species here is yet another tropical or southern hemisphere taxon that, like Mirothrips from Brazil ( Cavalleri et al. 2013), does not fully conform to the accepted classification.

Figures

FIGURES 1–8. Hoplothrips species. H. hongruiae sp. n. 1–5: (1) Head & pronotum; (2) Antenna; (3) Male sternite VIII; (4) Pelta & tergites II–III; (5) Prosternum & mesopresternum. (6) H. fungosus prosternites. Antennal segments III–IV 7–8: (7) H. corticis; (8) H. orientalis.