Heliothrips longisensibilis, Xie & Mound & Zhang, 2019

Xie, Yanlan, Mound, Laurence A. & Zhang, Hongrui, 2019, A new species of Heliothrips (Thysanoptera, Panchaetothripinae), based on morphological and molecular data, Zootaxa 4638 (1), pp. 143-150 : 145-149

Heliothrips longisensibilis sp. n.

( Figs 1–10 , 11, 13, 15 )

Female macroptera. Colour brown to dark brown ( Fig. 1 ); legs completely pale yellow; antennal segment I brown, II dark brown, III–V and basal two-thirds of VI yellow, apical third of VI brown, VII–VIII light brown ( Fig. 13 ); fore wing pale with extreme base and veins brown, clavus pale with base light brown ( Fig. 10 ).

Head sculptured with polygonal reticulation, slightly wider than long, anterior margin triangular, genae almost parallel but slightly concaved in the middle and constricted at base ( Fig. 4 ). Ocellar region not elevated, fore ocellus depressed in sculpture, setae minute. Antennae 8-segmented, constricted base of III much longer than the base of IV and V; III and IV each bearing simple sense cones, with the slender dorsal sense cone on IV much longer and extending to the middle or even third apical of VI ( Fig. 13 ); segment VIII much longer than VII; microtrichia absent. Mouth cone rounded apically, not extending beyond fore coxae, maxillary palps 2-segmented.

Pronotum transversely rounded, entirely covered with reticulations, setae small, prospinasternum forked apically ( Fig. 6 ). Mesoscutum with 4–5 narrow transverse rows of reticulation before median setae, almost rectangle ( Fig. 11 ), posteromedian short cleft. Metascutum with median sculptured triangle, posterior flange present, reaching anterior margin of metascutellum. Fore wing widened at base and rounded at apex, costal vein fused to first longitudinal vein with costal vein bearing approximately 7 setae, first vein 11–14 setae, second vein sparse 5–7 setae, setae minute; posterior fringe cilia straight except several cilia near cross vein wavy. Tarsi 1-segmented.

Abdominal tergites extensively reticulate, except submedian area of I–VII smooth, III–VIII with reticulations in front of antecostal ridge strongly developed ( Fig. 5 ); tergite I with a pair of median setae arising anterior to reticulate area ( Fig. 7 ), II–VIII median setae long and the base distance between them gradually wider on the posterior tergites, submedian setae close to campaniform sensilla (CPS); posterior margin of VIII with complete comb of long teeth ( Fig. 15 ); IX with 3 pairs of thorn-like setae, equal in size and length to the setae on X, tergites IX and X with microtrichia posteriorly, X with a complete longitudinal split. Sternites completely reticulate and with 3 pairs of small setae situated in front of posterior margin. Ovipositor long and well developed.

Measurements (holotype female in microns): Body length 1466. Head, length 165; width across genae 184. Pronotum, length 114; width 230. Fore wing length 600. Tergite V median setae length 32. Tergite VIII median setae length 45. Tergite IX length 135. Tergite X length 60. Antennal segments I–VIII length 20, 32, 62, 42, 38, 35, 12, 70; III simple sense cone length 25, IV dorsal sense cone length 69, ventral sense cone length 23.

Male macroptera. Similar to female but smaller ( Fig. 3 ). Body brown but with terminal abdominal segments paler ( Fig.3 ). Abdominal tergite IX with three pairs of stout thorn-like setae and the base of anterior pair nearly contiguous, each posterior pair of setae slightly slender and lateral to preceding pair ( Fig. 9 ). Sternites III–VII each with a transverse oblong pore plate ( Fig. 8 ).

Measurements (paratype male in microns): Body length 1138. Head, length 133; width across genae 165. Pronotum, length 101; width 212. Fore wing, length 600. Antennal segments I–VIII length 19, 30, 58, 37, 31, 29, 11, 62; III simple sense cone length 23, IV dorsal sense cone length 58, ventral sense cone length 20. Anterior pair of thorn-like setae on tergite IX length 19. Pore plate on sternite III length 95; width 14, on sternite VII length 59; width 14.

Material studied. Holotype female, CHINA, Yunnan Province, Xishuangbanna Tropical Botanical Garden , from leaves of Tecoma stans , 24.x.2017 (Xie Yanlan & Liu Hui), in collection of Yunnan Agricultural University, Kunming.

Paratypes: 14 females with same data as holotype; same location , 1 female from Melastoma candidum , 11.iii.2017; 1 female from Fagopyrum dibotrys , 11.iii.2017; 1 female from Cerasus glandulosa , 11.iii.2017; 10 females from Ixora chiensis , 24.viii.2018; 1 female from Albizia julibrissin , 30.v.2018. CHINA, Hainan Province, Jianfengling National Forest Park , 11 females and 2 males from Lithocarpus corneus leaves, 27.vi.2018 (with about 10 female specimens preserved in alcohol). [1 female, 1 male deposited in Australian National Insect Collection]

Molecular data. The DNA sequences were approximately 669 bp for COI, 620 bp for ITS 2, 380 bp for 28S rDNA and 189 bp for EF-1α, respectively, no pseudogene sequences were amplified. The neighbour-joining tree based on mitochondrial and concatenated nuclear datasets revealed that H. longisensibilis is well separated from H. haemorrhoidalis ( Fig. 17 ). Ten individuals of H. longisensibilis clustered into one branch and all H. haemorrhoidalis from different populations formed another clade. The genetic divergences between H. longisensibilis and H. haemorrhoidalis were 12.7–13.6% for mitochondrial COI sequences, 19.1–19.6% for ITS 2 sequences, 3.8–4.4% for EF-1α sequences, and 1.9% for the highly conserved 28S D3 domain sequences, respectively. After concatenating the three nuclear genes ( ITS 2+28S+ EF-1α), genetic divergences between H. longisensibilis and H. haemorrhoidalis were 10.3–10.4%, supporting the hypothesis that these are distinct species.

Figures

FIGURE 17. Neighbour-joining tree of two species of Heliothrips based on mitochondrial COI sequences (a) and combined nuclear ITS2+28S+EF-1α sequences (b), using Kimura 2-parameter distance. Bootstrap values are calculated in MEGA7.0 with 1000 replicates. Voucher number, species name, origin and GenBank Accession number are shown in the right column.

FIGURES 1–10. Heliothrips longisensibilis sp. n. (1) Female; (2) Teneral Female; (3) Male; (4) Head and pronotum; (5) Abdominal tergites IV–VI; (6) Prospinasternum; (7) Abdominal tergite I; (8) Abdominal sternites III–IV of male; (9) Abdominal tergites VIII–X of male; (10) Fore wing.

FIGURES 11–16. Heliothrips species from China. Meso– and metanotum, 11–12: (11) longisensibilis sp. n.; (12) haemorrhoidalis; Antennae, 13–14: (13) longisensibilis sp.n.; (14) haemorrhoidalis; Abdominal tergites VIII–X of female, 15–16: (15) longisensibilis sp. n.; (16) haemorrhoidalis.